news from BRE
published: 23/12/2009
BRE Trust reveals the results of DEC data analysis
The BRE Trust has carried out a unique data analysis project which interrogated the Display Energy Certificate (DEC) statistics of more than 28,000 public sector buildings. Results show that while DECs are valuable they do not provide evidence of real energy efficiency improvements and carbon emission reductions in public sector buildings.
The Display Energy Certificate (DEC) is a record of the building's metered energy usage and associated carbon emissions over a 12-month period, and compares these against established benchmarks to give a rating from A (best) to G (poorest).
Jon Mussett, Principal Sustainability Consultant at BRE said ‘Energy used in public buildings accounts for 4% of the UK's carbon emissions. Design standards are improving, but we need to demonstrate that this is resulting in improved building performance. This study found that the DEC ratings for some schools recently refurbished to higher energy efficiency standards under Building Schools for the Future and the Primary Capital Programme appeared to be no better than average. If expected savings are not being made, we need to learn the reasons why. DECs are important because they measure the carbon emissions from real buildings as they are used.'
It has been suggested that DECs should be made mandatory for all non-domestic buildings [1], to provide evidence of actual emissions and potential leverage for improvements. The BRE study found that the benchmarks were appropriate and that DECs were generally giving consistent results. However, up to 9% of DEC data is unreliable as a guide to the energy and carbon performance of buildings because default ratings are being used. This is most common for job centres (17%) and academies (23%). A further 2% of DECs were found to have values which are questionable in some way, for example, 37 % of A rated buildings, the most energy efficient category, are listed in the database with a zero rating.
Jon Mussett added ‘DECs are a potentially powerful source of information about the carbon performance of the public sector estate, but the results are hard to access and difficult to correlate with other datasets in order to draw meaningful conclusions to inform departmental carbon reduction strategies. Thousands of buildings are now producing DECs for the second year - the Government should seize this opportunity to detect and measure trends in carbon emissions in different parts of the public estate to help inform future policy.'
A full report on the finding of the research will be published by IHS/BRE press in the New Year.
[1] Committee on Climate Change Meeting Carbon Budgets - the need for step change 2009 http://www.theccc.org.uk/
For further information contact Linda McKeown tel 01923 664569, email mckeownl@bre.co.uk
Editors' notes
Display Energy Certificates
Since October 2008 occupiers of public buildings with floor areas of more than 1000m2 have been required to have a Display Energy Certificate (DEC). DECs are based on records of actual energy use and include an A-G energy rating for the building. The certificate is similar to those that are required for fridges and many other new white goods. The rating also includes a numerical rating: a typical building of its type would have a rating of 100.
Display Energy Certificates (DECs) became mandatory for many public buildings on 1 October 2008. The DEC is a record of the building's metered energy usage and associated carbon emissions over a 12-month period, and compares these against established benchmarks to give a rating from A (best) to G (poorest).
DECs are held on a public register, but can only be retrieved where their reference number is known. On 25 August, the BBC published DEC information for more than 28,000 public buildings. For the first time it has been possible to analyse this data and compare the energy performance of the buildings listed.
BRE
BRE has been building a better world for almost 90 years through cutting edge research, consultancy and testing services. Our unrivalled knowledge in regard to sustainability and innovation is now used across the construction industry and in the corporate world creating better buildings, communities and businesses. BRE is part of the BRE Group of companies owned by the BRE Trust, a registered charity. The profits made by BRE go to the BRE Trust, the largest UK charity dedicated specifically to research and education in the built environment. http://www.bre.co.uk/
BRE Trust
The BRE Trust is a charitable company whose objectives are through research and education, to advance knowledge, innovation and communication in all matters concerning the built environment for public benefit. Profits made by BRE and by the other subsidiary companies are passed to the Trust and used by it to promote its charitable objectives.
The Trust is the largest UK charity dedicated specifically to research and education in the built environment http://www.bretrust.org.uk/