1. Pre-Design
A. Appraisal
B. Design Brief
1.1. Obtain design brief
1.1.1. CIBSE guidance and tools
As part of government’s attempt to reduce contributions to the global climate change, while meeting the essential energy demand, city councils increasingly include or increase existing targets for on site power generation using renewable technologies, for new developments. This section aims to provide guidance and useful links, as well as recommendations for further guidance, to issues related to on site power generation using renewable technologies, as well as power distribution and use.
The building services engineer should be able to influence the design brief at an early stage in terms of energy efficiency, system options, sustainability, climate change, regulations etc. There are various ways to influence the brief and the following suggested guidance provides information relevant to some of the issues related to building design.
Energy conservation strategies e.g. metering and monitoring, renewable sources of energy and energy efficiency of systems are some of the issues associated with the design of electrical services. CIBSE Guide F “Energy Efficiency in Buildings” provides information on energy efficiency issues at various design stages, including information to be used at early design stages, such as the drivers for energy efficiency (chapter 1), setting energy objectives, criteria and targets, equipment and system selection (chapter 2) and developing a design strategy (chapter 3 and 4).
Furthermore, Guide F provides general information on LZC technologies (chapter 5) and control strategies (chapter 6). Part C of Guide F provides benchmarks of energy performance for various building applications and a series of CIBSE policy statements that reinforce the drivers for energy efficiency.
CIBSE Guide L “Sustainability” provides information on sustainability issues to help towards influencing the design brief (chapter 2), forming a sustainability strategy (chapter 3), including energy and low carbon strategy with reference to LZC technologies (§3.1), and adaptation to the impacts of climate change (§3.3).
CIBSE publications related to renewable technologies are the AM12 “Small-Scale Combined Heat and Power for Buildings”, TM25 “Understanding Building Integrated Photovoltaics and TM38 “Renewable Energy Sources for Buildings” with an accompanied simple tool to assist an initial identification of the most promising renewable sources for a given project.
CIBSE TM22 “Energy Assessment and Reporting Method” provides guidance and a methodology for monitoring energy use in buildings and associated carbon emissions. Even though recommended for post occupancy energy assessments the included tool could also be used at early design stage to provide an indication of the energy use in a proposed building.
CIBSE TM39 “Building Energy Metering” provides guidance towards developing and improving an energy metering strategy.
A more holistic approach of how to influence the design brief that combines energy efficiency, sustainability, cost, regulations, future performance; how certain design decisions could affect the above choices and their interrelations e.g. sustainability against capital, and whole life cost against building regulations requirements etc.
1.1.2. Weather data available for present climate conditions
At this pre-design stage of consulting with the client some general weather statistics based on location that will influence the use of electricity for cooling, heating, ventilation, lighting etc., could be used towards influencing the design brief in terms of energy efficiency and system option.
CIBSE Guide A “Environmental Design” (chapter 2) provides cold (§2.3) and warm (§2.4) weather data, including heating degree days and cooling degree hours, solar and illuminance data for various UK locations (§2.7) and wind data (§2.8), for various UK locations. CIBSE Guide J “Weather, Solar and Illuminance Data” also provides cold weather data (chapter 4, §4.1) and heating degree days (chapter 4, §4.3), warm weather data (chapter 4, §4.2) and cooling degree hours (chapter 4, §4.3), solar and illuminance data (chapter 5) and wind data (chapter 6), for the same UK locations.
The UKCIP08 publication “The Climate of the United Kingdom and Recent Trends” provides climate trends based on observed data (two baselines 1961-1990 and 1971-2000) presented at a 5km x 5km resolution, in a form of graphs and maps. The publication is freely available by UKCIP (http://www.ukcip.org.uk/).
The user should be looking for present day weather statistics that could influence the electricity demand and generation in a building or building site, based on location.
The weather data available in the CIBSE guides are location specific but not site specific. The user should take under consideration that locality and microclimate can considerably affect design decisions. Local information could be acquired from city councils, local planning authorities, environment agency, met office etc.
The data in Guides A and J are not at the moment consistent. Weather data in Guide A have been updated to a more recent baseline (1983-2002), while data in Guide J are based on an earlier baseline (1976-1995). The most up-to-date weather data currently available by CIBSE is located in Guide A, chapter 2. Although the weather data in Guide A have been recently updated, Guide J provides the background information on their production and selection processes that could enhance the understanding of the uncertainty associated with their use and as a result lead to more robust design decisions.
The baselines used for the production of weather data in Guides A and J do not include current manifestations of climate change, which could lead to the choice of unlike design conditions than the ones currently occurring.
The next generation of UKCIP climate change scenarios (UKCIP08), produced by the Met Office’s Hadley Centre, is expected to include weather information based on observed data as well as climate change model output. A variety of weather information based on observed data will be freely available through the UKCIP08 user interface (http://www.ukcip08.net/)
There are currently discussions that explore the ways to use future weather data, rather than present data based on past baselines, in building design. CIBSE’s Climate Task Force is examining the short and long term options (including the use of the forthcoming UKCIP08 information) of providing the industry with the best available weather information. Furthermore, a group of EPSRC funded projects are examining the use of UKCIP08 climate change information in building design.
Depending on the outputs of the above activities decisions will be made upon revising and further updating data in Guides A and J.
1.1.3. Weather data available for future climate conditions
At this pre-design stage of consulting with the client some general climate change statistics based on location could be used towards influencing the design brief in terms of climate change; possible impacts on building and building site and designing for the future conditions.
CIBSE Guide A “Environmental Design” (chapter 2, §2.9) and CIBSE Guide J “Weather, Solar and Illuminance Data” (chapter 3, §3.2) provide climate change trends for various emissions scenarios, for three UK locations (London, Manchester and Edinburgh); changes are based on a 1961-1990 baseline.
CIBSE Guide L “Sustainability” summarises climate changes for one emissions scenario and for the same three locations.
CIBSETM34 “Weather Data with Climate Change Scenarios” provide climate change data in the same format as in Guide J for assessing future system and building performance.
All current climate change data in CIBSE guidance originate from the Met Office’s Hadley Centre model outputs. Four UKCIP02 climate change scenarios are presented at a 50km x 50km resolution based on outputs from the Hadley Centre’s global and regional climate models (Had CM3 and HadRM3, respectively). For each of the four UKCIP02 climate change scenarios (H, M-H, M-L, L), changes are described for three future thirty-year time-slices: 2011 to 2040 (the 2020s), 2041 to 2070 (the 2050s) and 2071 to 2100 (the 2080s). All changes in climate are given relative to the baseline period of 1961 to 1990. For more information on emissions scenarios and the products freely available look at http://www.ukcip.org.uk/index.php?option=com_content&task=view&id=161&Itemid=291.
The next generation of climate change information (UKCP09) is currently available and presented in a probabilistic way ( http://ukclimateprojections.defra.gov.uk/). The UKCP09 provide information in various formats such as maps, graphs, plots, etc, available in printed reports and in customisable outputs. Changes in weather variables such as temperatures, rainfall, cloud cover etc are presented in a probabilistic way and are available for 25km grid squares, three emissions scenarios (Low, Medium and High) and seven future overlapping 30 year time periods. The provision of probabilistic projections is the major change from the previous UKCIP02 projections. Probabilistic projections assign a probability to different possible climate change outcomes, recognising the uncertainty involved in their production and inherent of our global climate, and as such help with making more robust adaptation decisions. A User Interface portal (http://ukclimateprojections.defra.gov.uk) has been specifically designed to guide the user to the information more appropriate to them and to explain the underlying science and outputs along the way. One of the resources provided through the User Interface is a Weather Generator which is a type of statistical model that uses relationships between climate variables to generate daily and hourly time series. The produced time series are comprised of set of climate variables at a 5 km resolution that are consistent with the underlying 25 km resolution climate projections. Customisable outputs, including the Weather Generator, are accessible after registration.
The user should be looking for future weather trends that could influence the electricity demand and generation in a building or building site, based on location.
The CIBSE climate change data (Guides A, J and TM34) are available for three locations only (London, Manchester and Edinburgh).
The data in Guides A and J are not at the moment consistent. Climate change data in Guide A is in accordance with UKCIP02 climate change scenarios (http://www.ukcip.org.uk/index.php?option=com_content&task=view&id=161&Itemid=291), while Guide J data is in accordance with the previous version of UKCIP98 climate change scenarios (http://www.ukcip.org.uk/index.php?option=com_content&task=view&id=255).
The climate change trends (in both UKCIP and CIBSE guidance) are based on a different baseline (1961–1990) than the present day statistics (Guide A 1983-2002 and Guide J 1976-1995), so they are not directly comparable.
The UKCIP02 scientific report (http://www.ukcip.org.uk/index.php?option=com_content&task=view&id=353&Itemid=408) provides seasonal changes of weather variables that could be used at this early design stage to influence design decisions. It should be noted that some variables like wind speed and cloud cover changes are assigned a higher uncertainty than some others, for example the temperature and rainfall changes.
All currently available climate change data and weather series for building design are based on UKCIP02 scenarios and are presented in a deterministic way which means that a single number is used to express future changes in weather variables. A good understanding of the uncertainty related to the development of climate change data is essential in order to assist in robust design decisions. Information on the uncertainty associated with climate change information could be found at http://www.ukcip.org.uk/index.php?option=com_content&task=view&id=232&Itemid=326.
Although the new climate projections UKCP09 offer an opportunity for the building professionals to better understand and apply climate change information in the future proofing of buildings, their complexity and existing format can hinder their immediate implementation in building design. One of the issues associated with the data is the lack of correlation between weather variables presented as maps and graphs (Cumulative Distribution Function – CDF and Probability Density Function – PDF). For example for overheating calculations there is no correlation between the temperature and solar radiation figures for a given probability. Other issues include the weakness of the Weather Generator to represent extreme events, as well as the lack of projections on wind speed and direction.
A group of EPSRC funded projects “Adaptation and Resilience in a Changing Climate” – ARCC are examining the use of probabilistic data and climate change information in building design. CIBSE is representing its members as a key stakeholder, technically co-ordinating the outputs of the projects. For more information and to get involved visit: http://www.ukcip-arcc.org.uk/
The outcomes from the above EPSRC funded projects will be integrated into the “Design Compass” as they emerge.
CIBSE’s suggestion of suitable external design conditions based on climate change data for use towards future proofing of buildings and their services should be made available and be incorporated in the weather related CIBSE guidance. Furthermore, CIBSE could further develop guidance on possible design options for adapting buildings to climate change, for both new built and refurbishments.
1.1.4. Other useful references
South East Climate Change Partnership “Adapting to Climate Change: a checklist for Developers”, November 2005
European Climate Assessment & Dataset (ECA&D) project for indices of extremes and daily information based on observations, for various European locations including UK: http://eca.knmi.nl/
1.1.5. Input from members
1.2. Identify client and building user needs and requirements
1.2.1. CIBSE guidance and tools
The building services engineers should be able to identify and acquire client requirements for electricity demand to be used while putting together the brief, so as to optimise design in terms of sustainability, energy efficiency, regulations, future needs etc. Such requirements could also include budget, required performance, attitude to risk, health and safety requirements etc.
An example of listing client and user needs and requirements is presented in CIBSE Knowledge Series publication KS8 “How to Design a Heating System”. Such a list could potentially be composed or customised by designers by using a series of CIBSE publications such as Guide A “Environmental Design” for internal environment requirements, Guide F “Energy Efficiency in Buildings” for energy efficiency requirements, Guide L “Sustainability”, Guide H “Building Control Systems” for control requirements, Guide K “Electricity in Buildings” for design requirements of electrical systems, etc.
CIBSE could offer a checklist of all relevant needs and requirements that the engineer could advise towards reaching objectives described in task 1.1.
1.2.2. Other useful references
1.2.3. Input from members
1.3. Refer to feedback and lessons learned from previous projects
1.3.1. CIBSE guidance and tools
The building services engineers should be able to keep in touch with previous projects in order to learn from them and improve their design methods. Some guidance on energy audits and surveys is included in Guide F, chapter 18.
Facilities managers (FMs) are usually responsible for the management of the building services and energy use in a building and have access to performance and energy use data. Liaising with the FMs during design process could provide useful information about the future operation and maintenance needs of a building and its services. Limited information on facilities and energy management is provided in Guide F, chapter 15.
Further guidance could include advice on possible channels and actions through which the design team could revisit or keep in touch with previous projects. Perhaps some research could be done in current practices.
Could CIBSE influence client perception of the value of monitoring and feedback? For example in some current projects monitoring and feedback is used as an educational process.
Further guidance could concentrate on encouraging integration with Facilities Management (FM), e.g. FM participation during design stages.
1.3.2. Other useful references
1.3.3. Input from members
1.4. Gather information about site, including utilities provision and fuel option
1.4.1. CIBSE guidance and tools
The building services engineers should make sure that they acquire all site specific information that could influence the design decisions.
CIBSE Guide F “Energy Efficiency in Buildings” (chapter 4, §4.1) and CIBSE Guide L “Sustainability” (chapter 3, §3.1) provide information on site analysis for reducing energy demand in buildings.
CIBSE Guide K “Electricity in Buildings” explains the various options for power generation on-site (chapter 4, §4.2).
Fuel choices, including electricity and renewable electricity generation, and environmental impact are included in CIBSE Guide B “Heating, Ventilation, Air Conditioning and Refrigeration”, chapter 1, §1.6, and in Guide F, chapter 5, §5.2.
A comprehensive checklist of all relevant site specific information and theri possible sources e.g. city councils, local planning authorities, environment agency, met office, site visits etc. could help at this stage.
1.4.2. Weather data available for present climate conditions
At this pre-design stage of gathering site information, general weather statistics and information of flooding, frost and other extreme events, based on location could influence decisions on the design and proofing of the electrical network.
CIBSE Guide A “Environmental Design” (chapter 2) provides cold (§2.3) and warm (§2.4) weather data, solar and illuminance data for various UK locations (§2.7) and wind data (§2.8), for various UK locations. CIBSE Guide J “Weather, Solar and Illuminance Data” also provides cold (chapter 4, §4.1) and warm weather data (chapter 4, §4.2), solar and illuminance data (chapter 5) and wind data (chapter 6), for the same UK locations.
The UKCIP08 publication “The Climate of the United Kingdom and Recent Trends” provides climate trends based on observed data (two baselines 1961-1990 and 1971-2000) presented at a 5km x 5km resolution, in a form of graphs and maps. The publication is freely available by UKCIP (http://www.ukcip.org.uk/).
The user should be looking for present day statistics of occurrence of weather events, average and extreme, that could affect externally positioned electrical equipment and also the on-site power generation, based on location.
The weather data available in the CIBSE guides are location specific but not site specific. The user should take under consideration that locality and microclimate can considerably affect design decisions. Local information could be acquired from city councils, local planning authorities, environment agency, met office etc.
The data in Guides A and J are not at the moment consistent. Weather data in Guide A have been updated to a more recent baseline (1983-2002), while data in Guide J are based on an earlier baseline (1976-1995). The most up-to-date weather data currently available by CIBSE is located in Guide A, chapter 2. Although the weather data in Guide A have been recently updated, Guide J provides the background information on their production and selection processes that could enhance the understanding of the uncertainty associated with their use and as a result lead to more robust design decisions.
The baselines used for the production of weather data in Guides A and J do not include current manifestations of climate change, which could lead to the choice of unlike design conditions than the ones currently occurring.
The next generation of UKCIP climate change scenarios (UKCIP08), produced by the Met Office’s Hadley Centre, is expected to include weather information based on observed data as well as climate change model output. A variety of weather information based on observed data will be freely available through the UKCIP08 user interface (http://www.ukcip08.net/).
There are currently discussions that explore the ways to use future weather data, rather than present data based on past baselines, in building design. CIBSE’s Climate Task Force is examining the short and long term options (including the use of the forthcoming UKCIP08 information) of providing the industry with the best available weather information. Furthermore, a group of EPSRC funded projects are examining the use of UKCIP08 climate change information in building design.
Depending on the outputs of the above activities decisions will be made upon revising and further updating data in Guides A and J.
1.4.3. Weather data available for future climate conditions
At this pre-design stage of gathering site information, some general climate change statistics based on location could assist in understanding the changes that the site might undergo over the lifetime of the building. Such information could help in future proofing the electrical infrastructure and develop a strategy for future on-site power generation.
CIBSE Guide A “Environmental Design” (chapter 2, §2.9) and CIBSE Guide J “Weather, Solar and Illuminance Data” (chapter 3, §3.2) provide climate change trends for various emissions scenarios, for three UK locations (London, Manchester and Edinburgh); changes are based on a 1961-1990 baseline.
CIBSE Guide L “Sustainability” summarises climate changes for one emissions scenario and for the same three locations.
CIBSE TM34 “Weather Data with Climate Change Scenarios” provide climate change data in the same format as in Guide J for assessing future system and building performance.
All current climate change data in CIBSE guidance originate from the Met Office’s Hadley Centre model outputs. Four UKCIP02 climate change scenarios are presented at a 50km x 50km resolution based on outputs from the Hadley Centre’s global and regional climate models (Had CM3 and HadRM3, respectively). For each of the four UKCIP02 climate change scenarios (H, M-H, M-L, L), changes are described for three future thirty-year time-slices: 2011 to 2040 (the 2020s), 2041 to 2070 (the 2050s) and 2071 to 2100 (the 2080s). All changes in climate are given relative to the baseline period of 1961 to 1990. For more information on emissions scenarios and the products freely available look at http://www.ukcip.org.uk/index.php?option=com_content&task=view&id=161&Itemid=291.
The next generation of climate change information (UKCP09) is currently available and presented in a probabilistic way ( http://ukclimateprojections.defra.gov.uk/). The UKCP09 provide information in various formats such as maps, graphs, plots, etc, available in printed reports and in customisable outputs. Changes in weather variables such as temperatures, rainfall, cloud cover etc are presented in a probabilistic way and are available for 25km grid squares, three emissions scenarios (Low, Medium and High) and seven future overlapping 30 year time periods. The provision of probabilistic projections is the major change from the previous UKCIP02 projections. Probabilistic projections assign a probability to different possible climate change outcomes, recognising the uncertainty involved in their production and inherent of our global climate, and as such help with making more robust adaptation decisions. A User Interface portal (http://ukclimateprojections.defra.gov.uk) has been specifically designed to guide the user to the information more appropriate to them and to explain the underlying science and outputs along the way. One of the resources provided through the User Interface is a Weather Generator which is a type of statistical model that uses relationships between climate variables to generate daily and hourly time series. The produced time series are comprised of set of climate variables at a 5 km resolution that are consistent with the underlying 25 km resolution climate projections. Customisable outputs, including the Weather Generator, are accessible after registration.
The user should be looking for future weather trends that could influence the electricity infrastructure and generation in a building or building site, based on location.
The CIBSE climate change data (Guides A, J and TM34) are available for three locations only (London, Manchester and Edinburgh).
The data in Guides A and J are not at the moment consistent. Climate change data in Guide A is in accordance with UKCIP02 climate change scenarios (http://www.ukcip.org.uk/index.php?option=com_content&task=view&id=161&Itemid=291), while Guide J data is in accordance with the previous version of UKCIP98 climate change scenarios (http://www.ukcip.org.uk/index.php?option=com_content&task=view&id=255).
The climate change trends (in both UKCIP and CIBSE guidance) are based on a different baseline (1961–1990) than the present day statistics (Guide A 1983-2002 and Guide J 1976-1995), so they are not directly comparable.
The UKCIP02 scientific report (http://www.ukcip.org.uk/index.php?option=com_content&task=view&id=353&Itemid=408) provides seasonal changes of weather variables that could be used at this early design stage to influence design decisions. It should be noted that some variables like wind speed and cloud cover changes are assigned a higher uncertainty than some others, for example the temperature and rainfall changes.
All currently available climate change data and weather series for building design are based on UKCIP02 scenarios and are presented in a deterministic way which means that a single number is used to express future changes in weather variables. A good understanding of the uncertainty related to the development of climate change data is essential in order to assist in robust design decisions. Information on the uncertainty associated with climate change information could be found at http://www.ukcip.org.uk/index.php?option=com_content&task=view&id=232&Itemid=326.
Although the new climate projections UKCP09 offer an opportunity for the building professionals to better understand and apply climate change information in the future proofing of buildings, their complexity and existing format can hinder their immediate implementation in building design. One of the issues associated with the data is the lack of correlation between weather variables presented as maps and graphs (Cumulative Distribution Function – CDF and Probability Density Function – PDF). For example for overheating calculations there is no correlation between the temperature and solar radiation figures for a given probability. Other issues include the weakness of the Weather Generator to represent extreme events, as well as the lack of projections on wind speed and direction.
A group of EPSRC funded projects “Adaptation and Resilience in a Changing Climate” – ARCC are examining the use of probabilistic data and climate change information in building design. CIBSE is representing its members as a key stakeholder, technically co-ordinating the outputs of the projects. For more information and to get involved visit: http://www.ukcip-arcc.org.uk/
The outcomes from the above EPSRC funded projects will be integrated into the “Design Compass” as they emerge.
CIBSE’s suggestion of suitable external design conditions based on climate change data for use towards future proofing of buildings and their services should be made available and be incorporated in the weather related CIBSE guidance. Furthermore, CIBSE could further develop guidance on possible design options for adapting buildings to climate change, for both new built and refurbishments.
1.4.4. Other useful references
Environment Agency’s Flood Map resource at: http://www.environment-agency.gov.uk/subjects/flood/826674/829803/
South East Climate Change Partnership “Adapting to Climate Change: a checklist for Developers”, November 2005
European Climate Assessment & Dataset (ECA&D) project for indices of extremes and daily information based on observations, for various European locations including UK: eca.knmi.nl
BRE (1990) ‘Climate and Site Development. Part 2: Influence of Microclimate’
1.4.5. Input from members
1.5. Obtain information on use of building, occupancy hours and on possible building form, fabric, etc.
1.5.1. CIBSE guidance and tools
The building services engineers should be able to acquire all building related information such as form and fabric details, building use and occupancy patterns, etc. An example of listing building specific information is presented in the CIBSE Knowledge Series publication KS8 “How to Design a Heating System” (§ 3.2).
CIBSE could further develop a checklist and guidance on where/how to acquire the relevant information e.g. client’s brief, by further questioning the client, design plans and details, etc.
1.5.2. Other useful references
1.5.3. Input from members
1.6. Establish and confirm design requirements from Regulations, Codes of Practice etc.
1.6.1. CIBSE guidance and tools
The building services engineers should be able to refer to all regulations, codes and standards that relate to the individual project. The most up-to-date references and links to specific regulations and codes are included in CIBSE Guide L “Sustainability”. Legislation regarding health issues associated with the building services could also be found in CIBSE TM40 “Health Issues in Building Services”. Specific regulations on health issues associated with the electrical services can be found in Guide K “Electricity in Buildings”, chapter 2.
CIBSE could further develop a comprehensive and dynamic list of all necessary documents and where to find them, download them etc, as well as possible future developments and updates.
1.6.2. Other useful references
1.6.3. Input from members
1.7. Establish requirements for use of on-site renewables
1.7.1. CIBSE guidance and tools
The building services engineers should be able to establish requirements for the use of LZC technologies e.g. check infrastructure, financing, environmental impact, planning requirements etc. CIBSE Guide L “Sustainability” provides guidance on LZC technologies options, environmental impact, current government targets and cost. Further guidance on the requirements for the installation and operation of LZC technologies could also be found in AM12 “Small-Scale Combined Heat and Power for Buildings”, TM25 “Understanding Building Integrated Photovoltaics” and TM38 “Renewable Energy Sources for Buildings”.
Guidance on potential impact of future developments of the surrounding area that could affect the effectiveness of the LZC technologies – e.g. future high buildings will affect solar availability, change in land use could improve performance, etc. CIBSE could further develop a comprehensive and dynamic list of all relevant documents and/or where to find them e.g. county councils, building regulations, application documents, etc.
1.7.2. Other useful references
Grants available for installing renewables: http://www.clear-skies.org/
‘Integrating renewable energy into new developments: Toolkit for planners, developers and consultants’: http://www.london.gov.uk/mayor/environment/energy/london_renew.jsp
Energy Saving Trust: http://www.energysavingtrust.org.uk/generate_your_own_energy
1.7.3. Input from members
2. Preliminary Design
C. Concept
D. Design development
2.1. Establish the key design data and parameters that relate to the design of the electrical system, including health and safety requirements, and the potential use of renewables
2.1.1. CIBSE guidance and tools
The building services engineer should be looking for guidance on how to establish internal and external design conditions in order to inform the design of the electricity network e.g. health and safety requirements for supply, generation and distribution of electric power etc.
CIBSE Guide A “Environmental Design” provides internal criteria (chapter 1, §1.11) and health issues associated with the generation, transmission and use of electricity (chapter 8, §8.6).
CIBSE TM40 “Health Issues in Building Services “ also provides comprehensive guidance on health issues associated with the operation and maintenance of building services.
CIBSE Guide K “Electricity on Buildings” explains legislation that regulates the way electricity is generated, distributed, operated, maintained and used (chapter 2). Earthing is explained in chapter 10, while electromagnetic compatibility regulations and legislation is further explained in chapter 11.
CIBSE Guide F “Energy Efficiency in Buildings” (chapter 5) and Guide L “Sustainability” (chapter 3, §3.1 and chapter 5, §5.1) provide general information on LZC technologies and design requirements.
Other CIBSE publications related to renewable technologies are the AM12 “Small-Scale Combined Heat and Power for Buildings”, TM25 “Understanding Building Integrated Photovoltaics and TM38 “Renewable Energy Sources for Buildings” with an accompanied simple tool to assist an initial identification of the most promising renewable sources for a given project.
The guidance is comprehensive at this design stage.
2.1.2. Weather data available for present climate conditions
Weather data at this preliminary design stage should be used to decide the external conditions for weather proofing of the electricity network and on-site power generation systems, and for assessing potential use of renewables.
CIBSE Guide A “Environmental Design” (chapter 2) provides cold (§2.3) and warm (§2.4) weather data, solar and illuminance data for various UK locations (§2.7) and wind data (§2.8), for various UK locations. CIBSE Guide J “Weather, Solar and Illuminance Data” also provides cold (chapter 4, §4.1) and warm weather data (chapter 4, §4.2), solar and illuminance data (chapter 5) and wind data (chapter 6), for the same UK locations.
The UKCIP08 publication “The Climate of the United Kingdom and Recent Trends” provides climate trends based on observed data (two baselines 1961-1990 and 1971-2000) presented at a 5km x 5km resolution, in a form of graphs and maps. The publication is freely available by UKCIP (http://www.ukcip.org.uk/).
The user should be looking for present day statistics of occurrence of weather events, average and extreme, that could affect externally positioned electrical equipment and also the on-site power generation, based on location. Observed statistics of solar availability and wind speed could be used for assessing the potential of renewables to generate electricity.
The weather data available in the CIBSE guides are location specific but not site specific. The user should take under consideration that locality and microclimate can considerably affect design decisions. Local information could be acquired from city councils, local planning authorities, environment agency, met office etc.
The data in Guides A and J are not at the moment consistent. Weather data in Guide A have been updated to a more recent baseline (1983-2002), while data in Guide J are based on an earlier baseline (1976-1995). The most up-to-date weather data currently available by CIBSE is located in Guide A, chapter 2. Although the weather data in Guide A have been recently updated, Guide J provides the background information on their production and selection processes that could enhance the understanding of the uncertainty associated with their use and as a result lead to more robust design decisions.
The baselines used for the production of weather data in Guides A and J do not include current manifestations of climate change, which could lead to the choice of unlike design conditions than the ones currently occurring.
Site specific information should be acquired for assessing potential use of renewables e.g. local wind, sunshine availability and elements blocking the sun around the site etc. Local information could be acquired from city councils, local planning authorities, environment agency, met office etc. and by site visits and discussions with client.
The next generation of UKCIP climate change scenarios (UKCIP08), produced by the Met Office’s Hadley Centre, is expected to include weather information based on observed data as well as climate change model output. A variety of weather information based on observed data will be freely available through the UKCIP08 user interface (http://www.ukcip08.net/).
There are currently discussions that explore the ways to use future weather data, rather than present data based on past baselines, in building design. CIBSE’s Climate Task Force is examining the short and long term options (including the use of the forthcoming UKCIP08 information) of providing the industry with the best available weather information. Furthermore, a group of EPSRC funded projects are examining the use of UKCIP08 climate change information in building design.
Depending on the outputs of the above activities decisions will be made upon revising and further updating data in Guides A and J.
2.1.3. Weather data available for future climate conditions
Climate change information at this preliminary design stage could be used to decide on the external conditions for weather proofing of the electricity network and on-site power generation systems over the lifetime of the building. Future trends could also be used here to assess the potential use of renewables to generate electricity.
CIBSE Guide A “Environmental Design” (chapter 2, §2.9) and CIBSE Guide J “Weather, Solar and Illuminance Data” (chapter 3, §3.2) provide climate change trends for various emissions scenarios, for three UK locations (London, Manchester and Edinburgh); changes are based on a 1961-1990 baseline.
CIBSE Guide L “Sustainability” summarises climate changes for one emissions scenario and for the same three locations.
CIBSE TM34 “Weather Data with Climate Change Scenarios” provide climate change data in the same format as in Guide J for assessing future system and building performance.
All current climate change data in CIBSE guidance originate from the Met Office’s Hadley Centre model outputs. Four UKCIP02 climate change scenarios are presented at a 50km x 50km resolution based on outputs from the Hadley Centre’s global and regional climate models (Had CM3 and HadRM3, respectively). For each of the four UKCIP02 climate change scenarios (H, M-H, M-L, L), changes are described for three future thirty-year time-slices: 2011 to 2040 (the 2020s), 2041 to 2070 (the 2050s) and 2071 to 2100 (the 2080s). All changes in climate are given relative to the baseline period of 1961 to 1990. For more information on emissions scenarios and the products freely available look at http://www.ukcip.org.uk/index.php?option=com_content&task=view&id=161&Itemid=291.
The next generation of climate change information (UKCP09) is currently available and presented in a probabilistic way ( http://ukclimateprojections.defra.gov.uk/). The UKCP09 provide information in various formats such as maps, graphs, plots, etc, available in printed reports and in customisable outputs. Changes in weather variables such as temperatures, rainfall, cloud cover etc are presented in a probabilistic way and are available for 25km grid squares, three emissions scenarios (Low, Medium and High) and seven future overlapping 30 year time periods. The provision of probabilistic projections is the major change from the previous UKCIP02 projections. Probabilistic projections assign a probability to different possible climate change outcomes, recognising the uncertainty involved in their production and inherent of our global climate, and as such help with making more robust adaptation decisions. A User Interface portal (http://ukclimateprojections.defra.gov.uk) has been specifically designed to guide the user to the information more appropriate to them and to explain the underlying science and outputs along the way. One of the resources provided through the User Interface is a Weather Generator which is a type of statistical model that uses relationships between climate variables to generate daily and hourly time series. The produced time series are comprised of set of climate variables at a 5 km resolution that are consistent with the underlying 25 km resolution climate projections. Customisable outputs, including the Weather Generator, are accessible after registration.
The user should be looking for probability of extreme events occurring in the future exceeded in the future. Future trends of solar availability and wind speed could be used for assessing the potential use of renewables for power generation.
All currently available climate change data and weather series for building design are based on UKCIP02 scenarios and are presented in a deterministic way which means that a single number is used to express future changes in weather variables. A good understanding of the uncertainty related to the development of climate change data is essential in order to assist in robust design decisions. Information on the uncertainty associated with climate change information could be found at http://www.ukcip.org.uk/index.php?option=com_content&task=view&id=232&Itemid=326.
CIBSE climate change data are available for three locations only (London, Manchester and Edinburgh).
The UKCIP02 scientific report (http://www.ukcip.org.uk/index.php?option=com_content&task=view&id=353&Itemid=408) provides seasonal changes of weather variables that could be used at this early design stage to influence design decisions. It should be noted that some variables like wind speed and cloud cover changes are assigned a higher uncertainty than some others, for example the temperature and rainfall changes.
The data in Guides A and J are not at the moment consistent. Climate change data in Guide A is in accordance with UKCIP02 climate change scenarios (http://www.ukcip.org.uk/index.php?option=com_content&task=view&id=161&Itemid=291), while Guide J data is in accordance with the previous version of UKCIP98 climate change scenarios (http://www.ukcip.org.uk/index.php?option=com_content&task=view&id=255).
Although the new climate projections UKCP09 offer an opportunity for the building professionals to better understand and apply climate change information in the future proofing of buildings, their complexity and existing format can hinder their immediate implementation in building design. One of the issues associated with the data is the lack of correlation between weather variables presented as maps and graphs (Cumulative Distribution Function – CDF and Probability Density Function – PDF). For example for overheating calculations there is no correlation between the temperature and solar radiation figures for a given probability. Other issues include the weakness of the Weather Generator to represent extreme events, as well as the lack of projections on wind speed and direction.
The climate change trends (in both UKCIP and CIBSE guidance) are based on a different baseline (1961 – 1990) than the present day statistics (Guide A 1983-2002 and Guide J 1976-1995), so they are not directly comparable.
A group of EPSRC funded projects “Adaptation and Resilience in a Changing Climate” – ARCC are examining the use of probabilistic data and climate change information in building design. CIBSE is representing its members as a key stakeholder, technically co-ordinating the outputs of the projects. For more information and to get involved visit: http://www.ukcip-arcc.org.uk/
The outcomes from the above EPSRC funded projects will be integrated into the “Design Compass” as they emerge.
CIBSE’s suggestion of suitable external design conditions based on climate change data for use towards future proofing of buildings and their services should be made available and be incorporated in the weather related CIBSE guidance. Furthermore, CIBSE could further develop guidance on possible design options for adapting buildings to climate change, for both new built and refurbishments.
2.1.4. Other useful references
European Climate Assessment & Dataset (ECA&D) project for indices of extremes and daily information based on observations, for various European locations including UK: http://eca.knmi.nl/
The British Wind Energy Association gives access to wind speeds in the UK: http://www.bwea.com/
The Building Regulations second tier document “Low or Zero Carbon Energy Sources: Strategic Guide” provides a simplified calculation tool for assessing the reduction in carbon emissions through the use of LZC technology: http://www.planningportal.gov.uk/uploads/br/BR_PDF_PTL_ZEROCARBONfinal.pdf
Geological surveys at the British Geological Survey: http://www.bgs.ac.uk/
Grants available for installing renewables: http://www.clear-skies.org/
Integrating renewable energy into new developments: Toolkit for planners, developers and consultants:
http://www.london.gov.uk/mayor/environment/energy/london_renew.jsp
Energy Saving Trust: http://www.energysavingtrust.org.uk/generate_your_own_energy
2.1.5. Input from members
2.2. Develop room design data sheets
2.2.1. CIBSE guidance and tools
The use of room data sheets (RDS) to define detailed performance requirements during design and specification of new build or refurbishment of buildings is common practice.
Such room data sheets were developed for the Carbon Trust’s Low Carbon Design Initiative (LCDI) to provide support to clients of the construction industry and their consultants/advisers, in developing design specifications for new building designs that will achieve a low carbon impact. Copies of the existing peer reviewed room data sheets, overarching technical briefing and other LCDI documents could be acquired from http://www.carbontrust.co.uk/about/reports/lcdi.
It should be noted that the above documents were originally intended to deal with school buildings, and their application to other building types should be undertaken with caution and additional client input.
Furthermore, the building services aspects of the LCDI room data sheets were mainly composed using the information in CIBSE guidance, e.g. CIBSE Guide A “Environmental Design”, Guide K “Electricity in Buildings” etc, and similarly the same guidance could be used to produce room data sheets for other building applications.
CIBSE could customise the above data sheets for use specifically by the building services engineers and for various types of buildings.
2.2.2. Other useful references
2.2.3. Input from members
2.3. Check that design parameters comply with legislation, energy targets etc.
2.3.1. CIBSE guidance and tools
Design parameters should be reviewed here to check that they comply with legislation and energy targets. A checklist of regulations, codes, standards etc, a sub category derived from the comprehensive list of task 1.6, could be used here that give specifications on design parameters and energy targets/benchmarks.
Guidance on ways to check the design is included in CIBSE Guide F “Energy Efficiency in Buildings”, chapter 13.
CIBSE could develop a dynamic list of possible documents to be used at this stage.
2.3.2. Other useful references
2.3.3. Input from members
2.4. Estimate building loads and maximum demand
2.4.1. CIBSE guidance and tools
Electricity benchmarks for non-domestic buildings could be used here to estimate typical and maximum demand. Guidance and benchmarks are available in CIBSE Guide F “Energy Efficiency in Buildings”, chapter 20, Guide K “Electricity in Buildings”, Guide D, “Transportation Systems in Buildings” and Guide A “Environmental Design”, chapter 6. The most up to date energy use benchmarks can be found in CIBSE TM36 “Energy Benchmarks”, while
Guide F provides a decision guide for estimation of likely power demands (chapter 2, figure 12.8).
CIBSE guidance seems sufficient at this design stage.
2.4.2. Other useful references
2.4.3. Input from members
2.5. Explore electricity demand met by renewables
2.5.1. CIBSE guidance and tools
Based on load estimation in task 2.4, the building services engineer could explore whether electricity demand could be met by renewables. Guidance on renewables and on-site power generation could be used here.
CIBSE Guide K “Electricity on Buildings” explains on-site power generation and the various options available (chapter 4, §4.2).
CIBSE Guide F “Energy Efficiency in Buildings” (chapter 5) and Guide L “Sustainability” (chapter 3, §3.1 and chapter 5, §5.1) provide general information on LZC technologies and design requirements.
Other CIBSE publications related to renewable technologies are the AM12 “Small-Scale Combined Heat and Power for Buildings”, TM25 “Understanding Building Integrated Photovoltaics and TM38 “Renewable Energy Sources for Buildings” with an accompanied simple tool to assist an initial identification of the most promising renewable sources for a given project.
CIBSE is not offering at the moment a calculation tool for the analysis of contribution from renewable energy sources and LZC technologies. It is an opportunity for CIBSE to develop a calculation tool that would provide a quantitative analysis of the potential use of such technologies as well as a cost and benefit analysis, for specific projects.
2.5.2. Weather data available for present climate conditions
At this preliminary design stage a good knowledge of the site and the microclimate is essential towards analysing the potential of various renewable resources and LZC technologies.
CIBSE Guide A “Environmental Design” (chapter 2, §2.7 and §2.8) and CIBSE Guide J “Weather, Solar and Illuminance Data” (chapters 5 and 6) provide solar and wind data, for various UK locations, that could be used for assessing potential use of renewables.
The UKCIP08 publication “The Climate of the United Kingdom and Recent Trends” provides wind speed trends based on observed data (two baselines 1961-1990 and 1971-2000) presented at a 5km x 5km resolution, in a form of maps. The publication is freely available by UKCIP (http://www.ukcip.org.uk).
The user should be looking for site specific weather data and local elements that could potentially affect the microclimate and/or the performance of renewable technologies.
The data in Guides A and J are not at the moment consistent. Wind data in Guide A have been updated to a more recent baseline (1983-2002), while data in Guide J are based on an earlier baseline (1976-1995). The most up-to-date weather data currently available by CIBSE is located in Guide A, chapter 2. Although the weather data in Guide A have been recently updated, Guide J provides the background information on their production and selection processes that could enhance the understanding of the uncertainty associated with their use and as a result lead to more robust design decisions.
The baselines used for the production of weather data in Guides A and J do not include current manifestations of climate change, which could arguably lead to the choice of unlike external design conditions than those currently occurring.
The CIBSE weather data are location specific but not site specific. Site specific information should be acquired for assessing potential use of renewables e.g. local wind, sunshine availability and elements blocking the sun around the site etc. Local information could be acquired from city councils, local planning authorities, environment agency, Met office etc. and by site visits and discussions with client.
The next generation of UKCIP climate change scenarios (UKCIP08), produced by the Met Office’s Hadley Centre, is expected to include weather information based on observed data as well as climate change model output. A variety of weather information based on observed data will be freely available through the UKCIP08 user interface (http://www.ukcip08.net).
There are currently discussions that explore the ways to use future weather data, rather than present data based on past baselines, in building design. CIBSE’s Climate Task Force is examining the short and long term options (including the use of the forthcoming UKCIP08 information) of providing the industry with the best available weather information. Furthermore, a group of EPSRC funded projects are examining the use of UKCIP08 climate change information in building design.
Depending on the outputs of the above activities decisions will be made upon revising and further updating the data in Guides A and J.
Guidance is required on the type of weather information needed for assessing potential of renewables and how to obtain such site specific information, e.g. Met Office, local weather station, city council archives etc.
2.5.3. Weather data available for future climate conditions
At this preliminary design stage a good understanding of the future weather trends and the microclimate of the site could help towards forming a strategy for improving the building’s carbon emissions by improving or incorporating LZC technologies and renewables.
CIBSE Guide A “Environmental Design” (chapter 2, §2.9) and CIBSE Guide J “Weather, Solar and Illuminance Data” (chapter 3, §3.2 and chapter 4, §4.4) provide climate change trends for various emissions scenarios, for three UK locations (London, Manchester and Edinburgh); changes are based on a 1961-1990 baseline.
CIBSE TM34 “Weather Data with Climate Change Scenarios” provide future changes in sunshine hours but not wind data.
All current climate change data in CIBSE guidance originate from the Met Office’s Hadley Centre model outputs. Four UKCIP02 climate change scenarios are presented at a 50km x 50km resolution based on outputs from the Hadley Centre’s global and regional climate models (Had CM3 and HadRM3, respectively). For each of the four UKCIP02 climate change scenarios (H, M-H, M-L, L), changes are described for three future thirty-year time-slices: 2011 to 2040 (the 2020s), 2041 to 2070 (the 2050s) and 2071 to 2100 (the 2080s). All changes in climate are given relative to the baseline period of 1961 to 1990. For more information on emissions scenarios and the products freely available look at http://www.ukcip.org.uk/index.php?option=com_content&task=view&id=161&Itemid=291.
The next generation of climate change information (UKCP09) is currently available and presented in a probabilistic way ( http://ukclimateprojections.defra.gov.uk/). The UKCP09 provide information in various formats such as maps, graphs, plots, etc, available in printed reports and in customisable outputs. Changes in weather variables such as temperatures, rainfall, cloud cover etc are presented in a probabilistic way and are available for 25km grid squares, three emissions scenarios (Low, Medium and High) and seven future overlapping 30 year time periods. The provision of probabilistic projections is the major change from the previous UKCIP02 projections. Probabilistic projections assign a probability to different possible climate change outcomes, recognising the uncertainty involved in their production and inherent of our global climate, and as such help with making more robust adaptation decisions. A User Interface portal (http://ukclimateprojections.defra.gov.uk) has been specifically designed to guide the user to the information more appropriate to them and to explain the underlying science and outputs along the way. One of the resources provided through the User Interface is a Weather Generator which is a type of statistical model that uses relationships between climate variables to generate daily and hourly time series. The produced time series are comprised of set of climate variables at a 5 km resolution that are consistent with the underlying 25 km resolution climate projections. Customisable outputs, including the Weather Generator, are accessible after registration.
The user should be looking for site specific weather data and local elements that could potentially affect the microclimate and/or the performance of renewable technologies.
All currently available climate change data and weather series for building design are based on UKCIP02 scenarios and are presented in a deterministic way which means that a single number is used to express future changes in weather variables. A good understanding of the uncertainty related to the development of climate change data is essential in order to assist in robust design decisions. Information on the uncertainty associated with climate change information could be found at http://www.ukcip.org.uk/index.php?option=com_content&task=view&id=232&Itemid=326.
Changes in sunshine hours included in TM34 could be used towards assessing future use of renewables, but there are no wind data available for wind technologies due to the lack of suitable algorithm to produce hourly wind speed data from the available daily averages (http://www.ukcip.org.uk/index.php?option=com_content&task=view&id=161&Itemid=291).
The UKCIP02 scientific report (http://www.ukcip.org.uk/index.php?option=com_content&task=view&id=353&Itemid=408) provides daily average wind speed and cloud cover changes, but extra caution should be taken when using these data since the associated uncertainty in higher than for example for the temperature and rainfall changes.
The data in Guides A and J are not at the moment consistent. Climate change data in Guide A is in accordance with UKCIP02 climate change scenarios (http://www.ukcip.org.uk/index.php?option=com_content&task=view&id=161&Itemid=291), while Guide J data is in accordance with the previous version of UKCIP98 climate change scenarios (http://www.ukcip.org.uk/index.php?option=com_content&task=view&id=255).
Although the new climate projections UKCP09 offer an opportunity for the building professionals to better understand and apply climate change information in the future proofing of buildings, their complexity and existing format can hinder their immediate implementation in building design. One of the issues associated with the data is the lack of correlation between weather variables presented as maps and graphs (Cumulative Distribution Function – CDF and Probability Density Function – PDF). For example for overheating calculations there is no correlation between the temperature and solar radiation figures for a given probability. Other issues include the weakness of the Weather Generator to represent extreme events, as well as the lack of projections on wind speed and direction.
The climate change trends (in both UKCIP and CIBSE guidance) are based on a different baseline (1961 – 1990) than the present day statistics (Guide A 1983-2002 and Guide J 1976-1995), so they are not directly comparable.
A group of EPSRC funded projects “Adaptation and Resilience in a Changing Climate” – ARCC are examining the use of probabilistic data and climate change information in building design. CIBSE is representing its members as a key stakeholder, technically co-ordinating the outputs of the projects. For more information and to get involved visit: http://www.ukcip-arcc.org.uk/
The outcomes from the above EPSRC funded projects will be integrated into the “Design Compass” as they emerge.
CIBSE’s suggestion of suitable external design conditions based on climate change data for use towards future proofing of buildings and their services should be made available and be incorporated in the weather related CIBSE guidance. Furthermore, CIBSE could further develop guidance on possible design options for adapting buildings to climate change, for both new built and refurbishments.
2.5.4. Other useful references
The British Wind Energy Association gives access to wind speeds in the UK: http://www.bwea.com/
The Building Regulations second tier document “Low or Zero Carbon Energy Sources: Strategic Guide” provides a simplified calculation tool for assessing the reduction in carbon emissions through the use of LZC technology: http://www.planningportal.gov.uk/uploads/br/BR_PDF_PTL_ZEROCARBONfinal.pdf
Geological surveys at the British Geological Survey: http://www.bgs.ac.uk/
Grants available for installing renewables: http://www.clear-skies.org/
Integrating renewable energy into new developments: Toolkit for planners, developers and consultants:
http://www.london.gov.uk/mayor/environment/energy/london_renew.jsp
Energy Saving Trust: http://www.energysavingtrust.org.uk/generate_your_own_energy
2.5.5. Input from members
2.6. Check whether standby generation is necessary
2.6.1. CIBSE guidance and tools
Different building applications will potentially require standby generation. Design considerations for designing a standby generation system can be found in Guide K “Electricity in Buildings”, chapter 4.
CIBSE guidance seems sufficient at this design stage.
2.6.2. Other useful references
2.6.3. Input from members
2.7. Explore energy conservation strategies
2.7.1. CIBSE guidance and tools
Metering and monitoring should be integrated in the design of the electrical systems as part of the energy conservation strategy. Relevant guidance for implementing metering and monitoring could be found in the CIBSE publications TM31 “Building Log Book Toolkit”, TM39 “Building Energy Metering”, TM22 “Energy Assessment and Reporting Method” and Guide F “Energy Efficiency in Buildings”, chapters 18, 19, 20.
CIBSE guidance seems sufficient at this design stage.
2.7.2. Other useful references
2.7.3. Input from members
2.8. Consider zoning requirements
2.8.1. CIBSE guidance and tools
Guidance on zoning based on space application, electricity demand, load variation and occupancy patterns is important at this stage in order to achieve optimum solutions for energy management, health and safety, maintenance, controls and metering, storage etc. Development of zoning requirements of the building could also help identify possible on-site generation solutions and their optimum positioning.
CIBSE could develop guidance on zoning requirements for the design of electric systems, including conservation of energy and on-site electricity generation.
2.8.2. Other useful references
2.8.3. Input from members
2.9. Explore supply voltage options
2.9.1. CIBSE guidance and tools
The choice of supply voltage will be based on building electricity demand and application. Guidance on high and low voltage systems can be found in CIBSE Guide K “Electricity in Buildings” chapters 5 and 7.
CIBSE guidance seems sufficient at this design stage.
2.9.2. Other useful references
2.9.3. Input from members
2.10. Explore voltage distribution system option and equipment
2.10.1. CIBSE guidance and tools
Guidance on high and low voltage distribution system and equipment, design considerations and option analysis can be found in CIBSE Guide K “Electricity in Buildings” chapters 5 and 7.
CIBSE guidance seems sufficient at this design stage.
2.10.2. Other useful references
Rigby, B (2005) “Design of Electrical Services for Buildings”, Spon Press
2.10.3. Input from members
2.11. Consider health and safety issues
2.11.1. CIBSE guidance and tools
Guidance on health and safety design considerations associated with the electrical systems including earthing, fire protection, protection against electric shock and control systems can be found in CIBSE Guide K “Electricity in Buildings” and also in Guide E “Fire Engineering”.
CIBSE guidance seems sufficient at this design stage.
2.11.2. Other useful references
Rigby, B (2005) “Design of Electrical Services for Buildings”, Spon Press
2.11.3. Input from members
2.12. Consider operating and control strategies, and building usage and layout data
2.12.1. CIBSE guidance and tools
The building services engineers should investigate the various control, maintenance and operating strategy options based on the electrical systems under consideration. Systems controls are not considered here since they are examined in the design of the heating, cooling etc systems, in other parts of the Design Compass. Under consideration here are the controls that are relevant to the distribution of electricity such as the shock protection controls. A checklist of information required, e.g. building plans, space usage, health and safety requirements etc, could be used here to inform the process.
CIBSE guidance on general principles on controls exists in CIBSE Guide H “Building Control Systems” and Knowledge Series KS4 “Understanding Controls”. CIBSE Guide K “Electricity in Buildings” explains controls that are relevant to the design of electrical services.
CIBSE Guide M “Maintenance Engineering and Management” also provides comprehensive guidance in the management, operation, maintenance and control of building services including electrical systems. Guide F, Part B, refers to management (chapter 15) and maintenance of building services (chapter 17), while the principles of building services management are analysed in the Knowledge Series publication KS5 “Making Buildings Work”.
CIBSE could provide a checklist of all requirements necessary for designing the control, maintenance and operation strategy of the electrical system.
2.12.2. Other useful references
Rigby, B (2005) “Design of Electrical Services for Buildings”, Spon Press
2.12.3. Input from members
2.13. Assess options against client requirements, performance, risk, energy use etc
2.13.1. CIBSE guidance and tools
The building services engineers should be able to follow a methodology for assessing the various options against a series of criteria set by the client, building regulations, standards etc. The assessment methods could include a series of consultations with the design team and the client, a prioritising strategy based on client’s brief etc. Assessing the various options identified could become critical when choosing between similar options.
CIBSE could provide a methodology for assessing options.
2.13.2. Other useful references
2.13.3. Input from members
2.14. Select proposed system
2.14.1. CIBSE guidance and tools
Based on the assessment of various options during task 2.13 the building services engineers should be able to identify the optimum solution based on client brief.
See task 2.13
2.14.2. Other useful references
2.14.3. Input from members
3. Design Development
E. Technical design
3.1. Calculate building loads and maximum demand
3.1.1. CIBSE guidance and tools
Rules of thumb and calculation tools for assessing loads and maximum demand based on building use and occupancy should be used here. Typical and benchmark loads exist in Guide K “Electricity in Buildings”, Guides F “Energy Efficiency in Buildings” and Guide A “Environmental Design”. The most up-to-date energy benchmarks exist in the CIBSE publication TM46 “Energy Benchmarks”. Tools for the calculation of the electricity loads also exist in Guide K, chapter 3, and for the calculation of electricity loads for transportation systems in Guide D “Transportation Systems in Buildings”.
It will be necessary at this stage to revisit occupancy patterns and room usage.
CIBSE could produce guidance on ways to reduce electricity demand.
3.1.2. Other useful references
3.1.3. Input from members
3.2. Calculate electricity demand met by renewables
3.2.1. CIBSE guidance and tools
Based on load calculation in task 3.1, the building services engineer could accurately calculate the electricity demand that could be met by renewables. Calculation tools and guidance on renewables and on-site power generation could be used here.
CIBSE Guide K “Electricity on Buildings” explains on-site power generation and the various options available (chapter 4, §4.2).
CIBSE Guide F “Energy Efficiency in Buildings” (chapter 5) and Guide L “Sustainability” (chapter 3, §3.1 and chapter 5, §5.1) provide general information on LZC technologies and design requirements.
Other CIBSE publications related to renewable technologies are the AM12 “Small-Scale Combined Heat and Power for Buildings”, TM25 “Understanding Building Integrated Photovoltaics and TM38 “Renewable Energy Sources for Buildings” with an accompanied simple tool to assist an initial identification of the most promising renewable sources for a given project.
CIBSE is not offering at the moment a calculation tool for the analysis of contribution from renewable energy sources and LZC technologies. It is an opportunity for CIBSE to develop a calculation tool that would provide a quantitative analysis of the potential use of such technologies as well as a cost and benefit analysis, for specific projects.
3.2.2. Weather data available for present climate conditions
At this advanced design stage a good knowledge of the site and the microclimate is essential for analysing the contribution of various renewable resources and LZC technologies.
CIBSE Guide A “Environmental Design” (chapter 2, §2.7 and §2.8) and CIBSE Guide J “Weather, Solar and Illuminance Data” (chapters 5 and 6) provide solar and wind data, for various UK locations, that could be used for assessing potential use of renewables.
The UKCIP08 publication “The Climate of the United Kingdom and Recent Trends” provides wind speed trends based on observed data (two baselines 1961-1990 and 1971-2000) presented at a 5km x 5km resolution, in a form of maps. The publication is freely available by UKCIP (http://www.ukcip.org.uk).
The user should be looking for site specific weather data and local elements that could potentially affect the microclimate and/or the performance of renewable technologies.
The data in Guides A and J are not at the moment consistent. Wind data in Guide A have been updated to a more recent baseline (1983-2002), while data in Guide J are based on an earlier baseline (1976-1995). The most up-to-date weather data currently available by CIBSE is located in Guide A, chapter 2. Although the weather data in Guide A have been recently updated, Guide J provides the background information on their production and selection processes that could enhance the understanding of the uncertainty associated with their use and as a result lead to more robust design decisions.
The baselines used for the production of weather data in Guides A and J do not include current manifestations of climate change, which could arguably lead to the choice of unlike external design conditions than those currently occurring.
The CIBSE weather data are location specific but not site specific. Site specific information should be acquired for assessing potential use of renewables e.g. local wind, sunshine availability and elements blocking the sun around the site etc. Local information could be acquired from city councils, local planning authorities, environment agency, Met office etc. and by site visits and discussions with client.
The next generation of UKCIP climate change scenarios (UKCIP08), produced by the Met Office’s Hadley Centre, is expected to include weather information based on observed data as well as climate change model output. A variety of weather information based on observed data will be freely available through the UKCIP08 user interface (http://www.ukcip08.net).
There are currently discussions that explore the ways to use future weather data, rather than present data based on past baselines, in building design. CIBSE’s Climate Task Force is examining the short and long term options (including the use of the forthcoming UKCIP08 information) of providing the industry with the best available weather information. Furthermore, a group of EPSRC funded projects examine the use of UKCIP08 climate change information in building design.
Depending on the outputs of the above activities decisions will be made upon revising and further updating the data in Guides A and J.
Guidance is required on the type of weather information needed for calculating contribution form renewables and how to obtain such site specific information, e.g. Met Office, local weather station, city council archives etc.
3.2.3. Weather data available for future climate conditions
At this advanced design stage a good understanding of the future weather trends and the microclimate of the site could help towards forming a strategy for improving the building’s carbon emissions by improving or incorporating LZC technologies and renewables.
CIBSE Guide A “Environmental Design” (chapter 2, §2.9) and CIBSE Guide J “Weather, Solar and Illuminance Data” (chapter 3, §3.2 and chapter 4, §4.4) provide climate change trends for various emissions scenarios, for three UK locations (London, Manchester and Edinburgh); changes are based on a 1961-1990 baseline.
CIBSE TM34 “Weather Data with Climate Change Scenarios” provide future changes in sunshine hours but not wind data.
All current climate change data in CIBSE guidance originate from the Met Office’s Hadley Centre model outputs. Four UKCIP02 climate change scenarios are presented at a 50km x 50km resolution based on outputs from the Hadley Centre’s global and regional climate models (Had CM3 and HadRM3, respectively). For each of the four UKCIP02 climate change scenarios (H, M-H, M-L, L), changes are described for three future thirty-year time-slices: 2011 to 2040 (the 2020s), 2041 to 2070 (the 2050s) and 2071 to 2100 (the 2080s). All changes in climate are given relative to the baseline period of 1961 to 1990. For more information on emissions scenarios and the products freely available look at http://www.ukcip.org.uk/index.php?option=com_content&task=view&id=161&Itemid=291.
The next generation of climate change information (UKCP09) is currently available and presented in a probabilistic way ( http://ukclimateprojections.defra.gov.uk/). The UKCP09 provide information in various formats such as maps, graphs, plots, etc, available in printed reports and in customisable outputs. Changes in weather variables such as temperatures, rainfall, cloud cover etc are presented in a probabilistic way and are available for 25km grid squares, three emissions scenarios (Low, Medium and High) and seven future overlapping 30 year time periods. The provision of probabilistic projections is the major change from the previous UKCIP02 projections. Probabilistic projections assign a probability to different possible climate change outcomes, recognising the uncertainty involved in their production and inherent of our global climate, and as such help with making more robust adaptation decisions. A User Interface portal (http://ukclimateprojections.defra.gov.uk) has been specifically designed to guide the user to the information more appropriate to them and to explain the underlying science and outputs along the way. One of the resources provided through the User Interface is a Weather Generator which is a type of statistical model that uses relationships between climate variables to generate daily and hourly time series. The produced time series are comprised of set of climate variables at a 5 km resolution that are consistent with the underlying 25 km resolution climate projections. Customisable outputs, including the Weather Generator, are accessible after registration.
The user should be looking for site specific weather data and local elements that could potentially affect the microclimate and/or the performance of renewable technologies.
All currently available climate change data and weather series for building design are based on UKCIP02 scenarios and are presented in a deterministic way which means that a single number is used to express future changes in weather variables. A good understanding of the uncertainty related to the development of climate change data is essential in order to assist in robust design decisions. Information on the uncertainty associated with climate change information could be found at http://www.ukcip.org.uk/index.php?option=com_content&task=view&id=232&Itemid=326.
Changes in sunshine hours included in TM34 could be used towards assessing future use of renewables, but there are no wind data available for wind technologies due to the lack of suitable algorithm to produce hourly wind speed data from the available daily averages (http://www.ukcip.org.uk/index.php?option=com_content&task=view&id=161&Itemid=291).
The UKCIP02 scientific report (http://www.ukcip.org.uk/index.php?option=com_content&task=view&id=353&Itemid=408) provides daily average wind speed and cloud cover changes, but extra caution should be taken when using these data since the associated uncertainty in higher than for example for the temperature and rainfall changes.
The data in Guides A and J are not at the moment consistent. Climate change data in Guide A is in accordance with UKCIP02 climate change scenarios (http://www.ukcip.org.uk/index.php?option=com_content&task=view&id=161&Itemid=291), while Guide J data is in accordance with the previous version of UKCIP98 climate change scenarios (http://www.ukcip.org.uk/index.php?option=com_content&task=view&id=255).
Although the new climate projections UKCP09 offer an opportunity for the building professionals to better understand and apply climate change information in the future proofing of buildings, their complexity and existing format can hinder their immediate implementation in building design. One of the issues associated with the data is the lack of correlation between weather variables presented as maps and graphs (Cumulative Distribution Function – CDF and Probability Density Function – PDF). For example for overheating calculations there is no correlation between the temperature and solar radiation figures for a given probability. Other issues include the weakness of the Weather Generator to represent extreme events, as well as the lack of projections on wind speed and direction.
The climate change trends (in both UKCIP and CIBSE guidance) are based on a different baseline (1961 – 1990) than the present day statistics (Guide A 1983-2002 and Guide J 1976-1995), so they are not directly comparable.
A group of EPSRC funded projects “Adaptation and Resilience in a Changing Climate” – ARCC are examining the use of probabilistic data and climate change information in building design. CIBSE is representing its members as a key stakeholder, technically co-ordinating the outputs of the projects. For more information and to get involved visit: http://www.ukcip-arcc.org.uk/
The outcomes from the above EPSRC funded projects will be integrated into the “Design Compass” as they emerge.
CIBSE’s suggestion of suitable external design conditions based on climate change data for use towards future proofing of buildings and their services should be made available and be incorporated in the weather related CIBSE guidance.
3.2.4. Other useful references
The British Wind Energy Association gives access to wind speeds in the UK: http://www.bwea.com/
The Building Regulations second tier document “Low or Zero Carbon Energy Sources: Strategic Guide” provides a simplified calculation tool for assessing the reduction in carbon emissions through the use of LZC technology: http://www.planningportal.gov.uk/uploads/br/BR_PDF_PTL_ZEROCARBONfinal.pdf
Geological surveys at the British Geological Survey: http://www.bgs.ac.uk/
Grants available for installing renewables: http://www.clear-skies.org/
Integrating renewable energy into new developments: Toolkit for planners, developers and consultants:
http://www.london.gov.uk/mayor/environment/energy/london_renew.jsp
Energy Saving Trust: http://www.energysavingtrust.org.uk/generate_your_own_energy
3.2.5. Input from members
3.3. Calaculate standby generation load
3.3.1. CIBSE guidance and tools
If standby generation is required (see task 2.6) then the load required should be estimated here.
Some guidance exists in Guide K “Electricity in Buildings”, chapter 9.
CIBSE could develop further guidance on the estimation of standby generation loads, especially when renewable sources of energy are in use.
3.3.2. Other useful references
3.3.3. Input from members
3.4. Check system selection provision still appropriate
3.4.1. CIBSE guidance and tools
The building services engineers should be using assessment methods to evaluate the option selected at task 2.14. The evaluation should be based on results from detailed calculations performed in the previous tasks of stage 3.
CIBSE could provide a checklist of possible criteria for the evaluation of selected systems.
3.4.2. Other useful references
3.4.3. Input from members
3.5. Check distribution layout considering balancing and regulating requirements
3.5.1. CIBSE guidance and tools
The building services engineers should be using guidance on electricity distribution layout based on voltage availability and power supply options. Extensive guidance could be found throughout CIBSE Guide K “Electricity in Buildings”.
CIBSE guidance seems sufficient.
3.5.2. Other useful references
Rigby, B (2005) “Design of Electrical Services for Buildings”, Spon Press
3.5.3. Input from members
3.6. Consider circuit layouts, connections and wiring choices
3.6.1. CIBSE guidance and tools
The building services engineers should be using guidance on circuit types, wiring options and design considerations and electricity distribution equipment. Extensive guidance could be found throughout CIBSE Guide K “Electricity in Buildings”.
CIBSE guidance seems sufficient.
3.6.2. Other useful references
Rigby, B (2005) “Design of Electrical Services for Buildings”, Spon Press
3.6.3. Input from members
3.7. Develop control requirements
3.7.1. CIBSE guidance and tools
The building services engineers should be using guidance on controls and control strategies for the design of electrical systems in order to develop the control requirements for the system selected. Systems controls are not considered here since they are examined in the design of the heating, cooling etc systems, in other parts of the Design Compass. Under consideration here are the controls that are relevant to the distribution of electricity such as the shock protection controls.
CIBSE guidance on general principles on controls exists in CIBSE Guide H “Building Control Systems” and Knowledge Series KS4 “Understanding Controls”. CIBSE Guide K “Electricity in Buildings” explains controls that are relevant to the design of electrical services.
CIBSE guidance seems sufficient.
3.7.2. Other useful references
Rigby, B (2005) “Design of Electrical Services for Buildings”, Spon Press
3.7.3. Input from members
3.8. Size and select voltage distribution network and equipment, and determine any distribution losses
3.8.1. CIBSE guidance and tools
Guidance, rules of thumb and calculation tools should be used here for the selection and sizing of the electrical system, including distribution network and equipment and to calculate distribution losses. Guidance could be found in CIBSE Guide K “Electricity in Buildings”.
CIBSE could further develop guidance on the application of computer tools for the design of the electrical systems.
3.8.2. Other useful references
Rigby, B (2005) “Design of Electrical Services for Buildings”, Spon Press
3.8.3. Input from members
3.9. Determine total connected load and maximum demand
3.9.1. CIBSE guidance and tools
Refer to results from task 3.1 to determine the building’s total loads and maximum connected demand. Tools for the calculation of the electricity loads exist in CIBSE Guide K “Electricity in Buildings”, chapter 3, and for the calculation of electricity loads for transportation systems in Guide D “Transportation Systems in Buildings”.
CIBSE could further develop guidance on the application of computer tools for the design of the electrical systems.
3.9.2. Other useful references
3.9.3. Input from members
3.10. Establish voltage variation, cut-off point and standby generation load
3.10.1. CIBSE guidance and tools
The electrical services engineer should be looking for guidance, calculation tools and computer tools that incorporate voltage variation, cut-off points and standby generation load in the overall design of the electrical system.
Some guidance exists in CIBSE Guide K “Electricity in Buildings”.
CIBSE could develop more detailed guidance especially when electricity is supplied from a combination of sources such as the grid as well as other on-site generation technologies. CIBSE could further develop guidance on the application of computer tools for the design of the electrical systems.
3.10.2. Other useful references
3.10.3. Input from members
3.11. Establish energy conservation strategy - monitoring and metering
3.11.1. CIBSE guidance and tools
The electrical services engineer should be looking for guidance on metering and monitoring techniques, energy audits and surveys, analysis of results and finding optimum solutions. Guidance could be found in CIBSE Guide F “Energy Efficiency in Buildings”, chapters 18,19, 20, TM31 “Building Log Book Toolkit”, TM39 “Building Energy Metering” and TM22 “Energy Assessment and Reporting Method”.
CIBSE could develop further guidance on analysing results and finding optimum solutions for reducing energy use.
3.11.2. Other useful references
3.11.3. Input from members
3.12. Consider any future requirements
3.12.1. CIBSE guidance and tools
The electrical services engineer should be able to assess possible changes in electricity loads that could affect the electrical system and how to address them, e.g. installation of mechanical systems, changes in building use etc.
CIBSE could develop guidance that addresses the above design considerations.
3.12.2. Other useful references
3.12.3. Input from members
3.13. Size and select power plant and switchboard
3.13.1. CIBSE guidance and tools
Guidance on the sizing and selecting power generation plants and switchboards exists in CIBSE Guide K “Electricity in Buildings”, chapters 4 and 7 respectively.
CIBSE guidance on electrical systems could further expand on the design of renewables e.g. selecting and sizing photovoltaics, wind turbines and CHPs, connections with the grid, etc.
3.13.2. Other useful references
Rigby, B (2005) “Design of Electrical Services for Buildings”, Spon Press
3.13.3. Input from members
3.14. Finalise controls
3.14.1. CIBSE guidance and tools
Based on the requirements outlined during task 3.7 the electrical services engineer should be able to finalise the controls required for the electrical system. CIBSE guidance on general principles on controls exists in CIBSE Guide H “Building Control Systems” and Knowledge Series KS4 “Understanding Controls”. CIBSE Guide K “Electricity in Buildings” explains controls that are relevant to the design of electrical services.
CIBSE guidance seems sufficient.
3.14.2. Other useful references
Rigby, B (2005) “Design of Electrical Services for Buildings”, Spon Press
3.14.3. Input from members
3.15. Check layouts and services co-ordination for clashes and ease of commissioning and maintenance
3.15.1. CIBSE guidance and tools
Guidance and outcomes from tasks 3.5 – 3.8 could be used here in order to check the layout of the electrical system, and any possible clashes with other systems.
Guidance on commissioning and maintenance can be found in CIBSE Guide M “Maintenance Engineering and Management”.
CIBSE Guide F “Energy Efficiency in Buildings” provides guidance on the commissioning process (chapter 14) and maintenance issues (chapter 17) in order to achieve expected efficiency.
CIBSE could add a commissioning code for electrical services to the existing available codes. Also further guidance on clashes of the electrical services with other building services could be useful here. CIBSE could further develop guidance on the application of computer tools for the design of the electrical systems.
3.15.2. Other useful references
Rigby, B (2005) “Design of Electrical Services for Buildings”, Spon Press
3.15.3. Input from members
3.16. Review system design and check predicted system performance
3.16.1. CIBSE guidance and tools
At this advanced design stage a review of the overall system design against targets and client requirements could concentrate on various aspects of the design intent. This task could concentrate on confirming that the energy targets and electricity demand is met.
CIBSE could further develop guidance on the application of computer tools for the design of the electrical systems.
3.16.2. Other useful references
3.16.3. Input from members
3.17. Check that the selected controls are capable of achieving the required level of control, response and energy efficiency
3.17.1. CIBSE guidance and tools
At this advanced design stage a review of the overall system design against targets and client requirements could concentrate on various aspects of the design intent. This task could concentrate on confirming that the controls are providing the required protection and energy efficiency.
CIBSE could further develop guidance on the application of computer tools for the design of the electrical systems.
3.17.2. Other useful references
3.17.3. Input from members
3.18. Check that final system and components meet client requirements for performance, quality, reliability, etc at acceptable cost; and also meet required energy targets and comply with regulations
3.18.1. CIBSE guidance and tools
This task is an overall confirmation of the design intent. Actions could include value engineering and confirming compliance with the health and safety and building regulations.
Building services engineers should be looking for guidance on value engineering and building regulations compliance tools. They should also make sure that there are no major alterations in the building’s envelope that have been done by the design team to affect the design of the electrical systems.
CIBSE could further develop guidance on the application of computer tools for the design of the electrical systems.
CIBSE could also provide guidance on how to complete a value engineering assessment and issues associated.
Finally, checklists of possible areas where last minute changes, e.g. by completing a value engineering assessment, could affect the performance of the electrical systems, could be beneficial towards maintaining performance of design intent.
3.18.2. Other useful references
3.18.3. Input from members
4. Pre-Construction
F. Production information
G. Tender documentation
H. Tender action
4.1. Information from Design Development to be used here
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4.2. CIBSE members’ involvement at this stage depends on the individual contract with the client
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5. Construction
J. Mobilisation
K. Construction to practical completion
5.1. CIBSE members' involvement at this stage depends on the individual contract with the client
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6. Post Completion
L. Post practical completion
6.1. Commissioning, management and maintenance of the electrical system
6.1.1. CIBSE guidance and tools
Guidance on the commissioning, management and maintenance of the building services, after the completion of the project, could be used here by facilities and energy managers in order to meet the design specifications.
CIBSE Guide K “Electricity in Buildings” could be used here towards informing the commissioning process of the electrical system. CIBSE Guide M “Maintenance Engineering and Management” provide guidance on the management and maintenance of the building services.
CIBSE could add a commissioning code for electrical services to the existing available codes.
6.1.2. Other useful references
6.1.3. Input from members
6.2. Design review - Refer to feedback and lessons learned
6.2.1. CIBSE guidance and tools
The building services engineers should be able to keep in touch with previous projects in order to learn from them and improve their design methods.
For post occupancy reviews see energy audits and surveys in Guide F “Energy Efficiency in Buildings”, chapter 18.
CIBSE could offer guidance on reviews at design stage (project team meetings, reviews with other design teams etc) and reviewing system performance at post occupancy.
Further guidance could include advice on possible channels and actions through which the design team could revisit or keep in touch with previous projects. Perhaps some research could be done in current practices.
Could CIBSE influence client perception of the value of monitoring and feedback? In some current projects monitoring and feedback is used as educational process.
Encourage integration with Facilities Management (FM), e.g. develop processes of reporting to the design team.
6.2.2. Other useful references
6.2.3. Input from members
6.3. End of life
6.3.1. CIBSE guidance and tools
Guidance on the building demolition and the recycling of materials is relevant here.
CIBSE Guide L “Sustainability”, chapter 8, provides some guidance on this last stage of the building’s life.
Further guidance is needed on end of life stage.
6.3.2. Other useful references
6.3.3. Input from members