Quantification of carbon emissions from the UK building stock Paul Davidson Director, Sustainable Energy November 2009
Overview Contribution of buildings to UK carbon emissions Modelling energy use in the UK buildings Technical and cost effective potential for carbon savings Scenario modelling Low and zero carbon new build Emission factors for delivered energy
Where the emissions come from Carbon Dioxide Emissions from UK Delivered Energy Use 2007 agriculture 1% transport 30% housing 28% commercial 13% industrial process 22% industrial building 3% public sector 3% BRE, 2009
Quantification for individual buildings Energy Performance Certificates now in place for all buildings Calculated based on standardised methodologies
Modelling energy flows Other gains Roof loss Solar gain Total space heating load Heat losses: Cooker Windows Fuel supply Appliances Walls Flue losses Boiler Ventilation BREDEM - BRE Domestic Energy Model Waste water Floor loss
SAP The Government s Standard Assessment Procedure for energy rating of dwellings SAP - the UK methodology for calculating energy performance of dwellings Calculation is carried out by a computer program based on SAP specification For existing buildings, RdSAP (Reduced Data) does the calculation with limited information
csap implements proposed SAP2009
SBEM for non-domestic buildings Current version v3.4.a released May 2009 Provides Building Regs compliance and EPCs in England, Wales, Scotland, N Ireland, Republic of Ireland and Jersey
End-use breakdown Total consumption 330 kwh/m 2 /yr Cooling and lighting dominate But other systems could be improved
Building stock energy models Housing BREHOMES First developed in 1970s Data on housing stock by type, tenure, age, size, location, etc Uses BREDEM to do energy calculations Uses various existing data sources, with the aim of making the best of what is available Principal source is market research surveys that started in the 1970s and has been carried out every year since Excellent long-term trend information on insulation and heating systems
Building stock energy models Non-Domestic N-DEEM Developed from 1990s Basic data on rateable premises (England and Wales) - detailed characteristics on 1.3 million of these. Energy Audits on range of premises (700 plus) Other Data sources as and when available Dynamic simulation model used to assess savings
How we use the models Technical support for UK climate change policy 15+ years Developing Scenarios Future changes in energy use and carbon emissions Business as usual With additional policy options With new and emerging technologies Cost abatement analysis Cost effectiveness of applying specific energy efficiency measures across the building stock Feeds into cost benefit analysis for policy options
BREHOMES - Loft insulation trend Ownership of loft insulation 100% 90% 80% 70% Not stated <1" 1" 2" 3" 4" or more Percentage of potential 60% 50% 40% 30% 20% 10% 0% 1974 1976 1978 1980 1982 1984 1986 1988 1990 1992 1994 1996 1998 2000 2002 2004 2006 Year
Delivered Energy Use broken down by End use for Non-domestic Buildings - 2007 Annual Delivered Energy Consumption from Non-Domestic Buildings warehouses schools retail other service sector other government Building type leisure hospitality health government estate further and higher education communication and transport commercial office industrial buildings 0 10000 20000 30000 40000 50000 60000 GWh pa catering computing cooling hot water lighting other space heating
Developing scenarios for future energy use and carbon emissions Market penetration of home energy efficiency measures 100% 90% Hot water tank insulation 80% Draught proofing Double glazing Percentage of potential 70% 60% 50% 40% 30% Central heating Condensing boilers Cavity wall insulation 20% 10% Loft insulation (any) 0% 1950 1960 1970 1980 1990 2000 2010 2020 2030 2040 2050 Year
Scenarios for UK Service Sector Emissions 25 20 Annual emissions (MtC) 15 10 reference policy extended policy step change 1 step change 2 60% below 1990 5-2005 2010 2015 2020 2025 2030 2035 2040 2045 2050 Year
Zero Carbon New Build Is it feasible? Are there building types where it might be difficult to achieve zero carbon? How much will it cost
Feasibility of zero carbon new build for non-domestic buildings CO 2 Emissions from new build to 2006 regs Industrial 600 Other Services Tonnes CO2 pa 500 400 300 200 Warehouses Sport and Leisure Retail Hotel Health Government Preliminary assessment based on few example buildings 100 Education - Heating Cooling Auxiliary Lighting DHW Equip End use Communications and Transport Commercial Offices CO 2 Emissions from new build to max building regulations plus solar thermal hot water and biomass boilers and PV Tonnes CO2 pa 600 500 400 300 200 100 0 Heating Cooling Auxiliary Lighting DHW Equip End use Industrial Other Services Warehouses Sport and Leisure Retail Hotel Health Government Education Communications and Transport Commercial Offices
Zero carbon new buildings v existing stock 40,000 Number of dwellings (000) 35,000 30,000 25,000 20,000 15,000 10,000 Post 2005 Stock Pre 2005 stock 30% 70% 5,000 0 2000 2005 2010 2015 2020 2025 2030 2035 2040 2045 2050 Year Source: Housing Statistics ODPM 2004
Cost effectiveness of carbon dioxide emission savings in existing dwellings Cost effectiveness of carbon dioxide emission savings in the existing stock 700 Micro wind turbines 600 Net annual cost of carbon saved ( /tco2) 500 400 300 200 100 0-100 -200 A-rated cold appliances A-rated wet appliances Double glazing Insulated doors Post 1983 cavity wall insulation 1976-83 cavity wall insulation Solid wall insulation Mini wind turbines Solar water heating A-rated condensing boiler Pre-1976 cavity wall insulation -300 0 20 40 60 80 100 120 140 160 Carbon saving potential (MtCO2/yr) Photovoltaic panels From Do zero carbon homes make sense? Shorrock & Henderson, BRE. Proc. ECEEE Summer Study, June 2009. Also to be published in a BRE Trust report.
Cost effectiveness of emission savings in the existing stock plus Code level 6 for all new homes Cost effectiveness of carbon dioxide emission savings in the existing stock (Code level 6 carbon dioxide emission savings in new homes also shown) 700 600 Code for Sustainable Homes level 6 500 Net annual cost of carbon saved ( /tco2) 400 300 200 100 0-100 -200-300 0 20 40 60 80 100 120 140 160 Carbon saving potential (MtCO2/yr)
Carbon savings from each Level of the Code for Sustainable Homes compared to those possible from improving existing homes Note: only cost-effective savings from improving existing homes are shown here additional savings would be possible if non cost-effective measures were included
Carbon dioxide emission reductions in 2050 relative to 1990 compared with the 80% target Carbon dioxide emission reductions in 2050 relative to 1990 (assuming that all cost-effective measures in existing homes are undertaken and that new homes are built to 2006 Regulations or one of the six levels of the Code for Sustainable Homes) 0% Level of the Code for Sustainable Homes to which new homes are built 2006 Regulations Level 1 Level 2 Level 3 Level 4 Level 5 Level 6 10% Percentage of 1990 emissions (154.4 MtCO 2 ) 20% 30% 40% 50% 60% 70% 80% 90% 75.2 MtCO 2 saved 76.6 MtCO 2 saved 77.7 MtCO 2 saved 78.6 MtCO 2 saved 80% target (123.5 MtCO 2 saved) 81.2 MtCO 2 saved 88.8 MtCO 2 saved 25 MtCO 2 shortfall in savings which will have to be made up by de-carbonising the supply of electricity and heat 98.4 MtCO 2 saved 100%
Cost effectiveness of carbon dioxide emission savings in the nondomestic stock (with savings for Levels 1 4 for new non-domestic buildings also shown) Provisional Results
Also similar report for non-domestic Both can be downloaded from BRE website: www.bre.co.uk/energy Forthcoming publication from BRE Trust late 2009: Zero carbon new build and energy efficient refurbishment of existing building stock
SAP Emission Factors Previously CO 2 only Covers important upstream emission sources Proposed from 2010 All significant GHG More comprehensive coverage of upstream emissions Consistent treatment of all fuels Issues Consistency with other factors - Act on CO 2,, Company reporting guidelines, Factors used for policy assessment, Road Transport Fuel Obligation for biofuels future change in generation mix for electricity is uncertain
Summary Buildings account for 46% of UK carbon emissions more if embodied carbon emissions are taken into account Modelling energy use in the UK building stock: Identify technical and cost effective potential for carbon savings CE potential of the existing stock is significant Scenario modelling indicates that achieving 80% reduction by 2050 requires uptake of existing cost effective potential, plus significant uptake of low carbon technologies Zero carbon new build More expensive than tackling existing building stock (probably not achievable for all nondomestic buildings) and won t save enough carbon. Even when upgrading the existing stock and zero carbon new build combined, not sufficient to achieve an 80% reduction in emissions by 2050 Emission factors for delivered energy Important that factors reflect real impact but direction of future change for electricity is uncertain