Background: Existing building sector and CO 2 emissions Case of UK, USA and India. Review of typical benchmarks and standards.

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1 A critical and comparative evaluation of approaches and policies to measure, benchmark, reduce and manage CO 2 emissions from energy use in the existing building stock of developed and rapidlydeveloping countries - case studies of UK, USA, and India 5 th Urban Research Symposium Cities and Climate Change: Responding to an Urgent Agenda June 28-30, 2009 Marseille, France Dr Rajat Gupta, Oxford Institute for Sustainable Development, UK; Smita Chandiwala rgupta@brookes.ac.uk Structure of presentation Background: Existing building sector and CO 2 emissions Case of UK, USA and India Methodology of research Measuring energy use and CO 2 emissions from existing buildings Approaches and methodologies Benchmarking energy use and CO 2 emissions Review of typical benchmarks and standards. Reducing energy use and CO 2 emissions from existing buildings Energy efficiency versus carbon intensity Managing energy use and CO 2 emissions i Policy instruments Conclusions and some final words

2 Background: Cities, buildings and CO 2 emissions Energy use in buildings and CO 2 emissions: Climate change and the Building stock Mitigation In 2002, buildings were responsible for 7.85Gt, or 33% of all energy-related CO 2 emissions worldwide. And these emissions i are expected to grow to 11Gt (B2 scenario) or 15.6Gt (A1B scenario) by Impact of climate change: Adaptation Possible increases in the intensity of tropical storms or in the intensity of heavy rainfall events will directly impact buildings. Heating energy use will decrease, the demand for cooling will increase. Many passive and low-energy techniques for cooling buildings (evaporative cooling, or night ventilation) may become less effective as heat waves become more intense and longer-lasting

3 CO 2 emissions from building energy use On-site: Emissions from fuels combustion (space heating) Off-site: Emissions from public electricity use and district heat consumption. Globally, the building sector is responsible for 42% of electricity consumption more than any other sector. Buildings energy consumption outlook Energy use in buildings will grow by 34% in the next 20 years, at an average rate of 1.5% (EIA, 2006).

4 CO 2 emissions from building energy use: total and per-capita Depends on the degree of electrification, level of urbanization, amount of building area per capita, prevailing climate, as well as national and local policies to promote efficiency. (Source: IEA, 2004) CO 2 emissions by sector in UK, USA and India UK USA India Transport 33% Agriculture 1% Domestic buildings 26% Agriculture 31% Transportation 3% Residential 23% Commercial and public buildings 13% Commercial 7% Industrial process 22% Industrial buildings 5% Industrial 36% 45% 48% 30% UK CO 2 emissions by sector, 2002 USA CO 2 emissions by sector, 2005 Electricity use by sector, 2005

5 Climate change policy in UK, USA and India UK Climate Change Act 2008 USA Climate Change Bill 2009 India NAPCC 2008 Cut CO 2 emissions by 26-32% from 1990 levels in 2020 and 80% in Cut CO 2 emissions by 17% from 2005 levels in 2020 and 83% in India has to engage actively in multilateral negotiations on UNFCCC. Implemented through 8 National Missions. Economic recovery packages and green investments

6 UK Most of the focus has been on new-build USA India 3. New Buildings - 50% % % % % Carbon Neutral (no fossil fuel energy to operate) Relevance of existing building sector New construction projected to grow by 5% annually in India, only 2% in the US and 1% in UK. May reduce further due to economic slowdown. Existing building stock will continue to form the largest proportion of the built environment in the future: yet its current energy and carbon efficiency i is extremely poor. In UK, 75% of the housing stock existing today will be present by Refurbishment of existing stock may gather pace in an economic slowdown. UK retrofitting industry estimated to be worth - 3.5billion - 7 billion. Improvement of the existing building sector is significant for carbon abatement in the medium to long term.

7 Case of UK Carbon footprint: Domestic and Non-domestic buildings Other 5% Process 4% Catering 11% Computing 4% Lighting 26% Cooling & ventilation 6% Hot water 7% Space heating 37% UK housing stock energy-related CO 2 emissions by end-use for 2005 (DEFRA) CO 2 emissions by end use in non-domestic buildings for 2005 (DEFRA) Direct CO 2 emissions that arise from building energy demand: Onsite (heating) and Offsite (electricity production)

8 Energy performance of existing domestic stock The existing stock is in a poor state - half the homes are pre The majority of existing houses lie towards the bottom of the SAP scale. Existing commercial/industrial stock (England & Wales) Non-domestic stock more modern than the housing stock. Half of all commercial and industrial properties were built before 1940 and only 9% after 1990 (Source: Foresight, 2000)

9 2020 target CO 2 and renewable energy Targets for UK housing National Energy Efficiency Action Plan target to reduce emissions from UK s housing stock by 31% on 1990 levels by Heat and Energy Saving Strategy consultation 2009 Sets out an aim for emissions from existing buildings to be approaching zero by All homes to have received by 2030 a whole house package. UK Renewable energy target % of UK energy be sourced from renewables by Widespread deployment of micro-generation installations in housing. Case of USA

10 Carbon footprint: Domestic and Non-domestic buildings Computers 1% Wet Clean 6% Cooking 5% Adjust to SEDS 6% Other 4% Space Heating 26% Refrigeration 7% Electronics 8% Lighting 12% Water Heating 12% Space Cooling 13% US residential CO 2 emissions US commercial CO 2 emissions Residential sector consumed 37% of all electricity produced in US About 80% of all CO2 attributed to the commercial sector comes from electricity consumption. Case of India

11 Overview of energy scenario Per capita energy and electricity consumption = one fifth of world average Per capita electricity consumption in India is about 630 kwh To sustain the current rate of economic growth of 8-10%, commensurate growth rate of energy supply of about 5-6% has to be ensured Construction sector contributes to nearly 10% of India s GDP and growing at about 9-10% Peak demand shortage is approximately 11% - 13% Peak demand shortage can be overcome through energy efficiency measures in the short and medium term. Energy saving potential is expected to be about 20% in buildings. Carbon footprint: Domestic and Non-domestic buildings Refrigeration 13% EV Cooler 4% TV 4% Others 10% Lighting 28% A/c 7% HVAC 32% Others 8% Lighting 60% Fans 34% Energy consumption in residential sector, 116 billion units Energy consumption in commercial sector, 33 billion units

12 Spiralling urban growth The Context: Spiraling urban growth In the next five years Housing Hotels Retail space Retail in space mallsin malls Commercial space 20 million dwelling units 50,000 rooms 13 million m2 19 million m2 Statistics released by the Bureau of Energy Efficiency, show the dominance of residential buildings compared to other sectors of building construction (Source: Professor Ashok Lall, Windsor conference 2008) Electricity use in commercial sector is exploding (Source: ABPS Infrastructure Private Limited, 2009)

13 Voluntary introduction of ECBC in May 2007; mandatory after capacity building and implementation experience ECBC is applicable to new commercial buildings having connected load of 500KW or 600 KVA and above. Old buildings having connected load / energy consumption beyond a prescribed limit will be audited. ECBC covers the following components: Building envelope (walls, roofs, windows) Lighting (Indoor and Outdoor) Heating ventilation and air conditioning (HVAC) system Solar hot water heating Electrical systems Building Energy Code: ECBC Measuring energy use and CO 2 emissions from existing buildings: Case of UK, USA and India

14 Building energy use in UK, USA and India Criteria National benchmarking databases BERR DOE Individual study estimates* Dwellings UK (2007) USA (2005) India Total number of households million million Data unavailable Energy use per unit area 239 kwh/m2/yr 138 kwh/m2/yr Data unavailable Energy use per household 19,851 kwh/house/yr 27,815 kwh/house/yr Data unavailable Non-domestic UK (2005) USA (2003) India Energy per unit area kwh/m2/yr kwh/m2/yr 189 kwh/m2/yr Approaches for measuring energy use in buildings 1. Predictive simulation models - UK s BREDEM, US Energy Plus 2. Simplified energy models or Correlation tools - UK s Standard Assessment Procedure (SAP) for dwellings 3. Scorecard rating tools - LEED (US), BREEAM (UK), Griha (India) 4. Actual energy use based on energy auditing - For buildings, actual data is known by fuel (gas, electricity it etc) t) or by end use (heating, cooling, appliances) if buildings are specifically sub-metered.

15 Prediction and Actual: Credibility gap? Source: Bill Bordass, 2005 EU Directive of Building Energy Performance (EPBD)

16 Approaches for measuring energy use: Energy labelling Direct CO2 emissions from building energy demand Sources of end use Heating Hot water Cooling Ventilation Lighting Appliances/ equipment Imperfect control Aspects of demand Roof, walls, windows, floors Boilers, etc Lowflowshowers Solar shading Thermal mass Passivent Lamp efficacy Low C design 30C Low C IT Smart meters Displays Standby losses BMS Asset Rating Energy Performance Certificate (EPC) Standard use (Calculated) Carbon counters Operational Rating Display Energy Certificate (DEC) Actual use (Metered) Inefficient behaviour Knowledge Motivation Incentives Source: Robert Cohen, Energy for Sustainable Development, 2007 Comparison of environmental rating systems: UK, USA, India

17 Comparison of environmental rating systems: UK, USA, India DECoRuM energy & CO 2 model: Bottom-up carbon counting Rajat Gupta 2006

18 DECoRuM CO 2 reduction model: estimating solar potential Local authorities and DECoRuM Provides a GIS-based toolkit to enable LAs to develop a carbon foot-printing capability to : - Assess and map the current carbon emissions of their building stock. - Benchmark baseline emissions against typical and good-practice standards. - Identify hotpots of energy use. - Establish robust carbon emission reduction targets. - Evaluate strategies and technologies to achieve those targets in terms of carbon reduction and cost-benefits. - Verify and monitor the reductions achieved.

19 Benchmarking energy use and CO 2 emissions from existing buildings: Case of UK, USA and India UK: CIBSE TM46 Benchmarks for Typical energy use Energy Benchmarks Name Electricity typical benchmark (kwh/m 2 ) Illustrative benchmarks calculated from the energy benchmarks Fossil-thermal typical benchmark (kwh/m 2 ) Illustrative electricity typical benchmark (kgco /m 2 2 ) Illustrative fossilthermal typical benchmark (kgco 2 /m 2 ) Illustrative total typical benchmark (kgco 2 /m 2 ) General office General retail Hotel Fitness and health centre Dry sports and leisure facility Public buildings with light usage Schools and seasonal public buildings University it campus Hospital (clinical and research) Long term residential General accommodation

20 USA: CBECS 2003 National Average Energy Use Index Building Use Description Average Source EUI (kbtu/sqft) Average Percent Electric Average Site EUI (kbtu/sqft) Education % 76 K-12 School See Target Finder/ Portfolio Manager College / University (Campus-level) % 120 Food Service % 351 Restaurant / Cafeteria % 302 Fast Food % 534 Health Care: Long term care % 124 (Nursing home, Assisted living) Health care: Outpatient % 73 Clinic/ Other Outpatient Health % 84 Medical Office See Target Finder/ Portfolio Manager Lodging % 87 Dormitory/ Fraternity/ Sorority See Target Finder/ Portfolio Manager Hotel, Motel or Inn See Target Finder/ Portfolio Manager Mall (Strip Mall and Enclosed) % 107 Office See Target Finder/ Portfolio Manager Bank / Financial Institution See Target Finder/ Portfolio Manager Public Assembly % 66 Entertainment / Culture % 95 Library % 104 Recreation % 65 Social/ Meeting % 52 Retail (Non-mall stores, Vehicle % 82 Dealerships) Retail stores See Target Finder/ Portfolio Manager Other % 104 India: ECBC-compliant building Benchmarks proposed by ECBC: National Benchmark ~ 180 kwh/m 2 /year ECBC-compliant building ~ 110 kwh/m 2 /year Within the building sector, energy intensity is polarised (Source: ECO-III project, 2009)

21 Comparative evaluation of benchmarks: UK, USA and India Building Type UK (kwh/m2/yr) USA (kwh/m2/yr) India (kwh/m2/yr) Retail School Offices Hotels Supermarkets Restaurants Hospitals Dwellings Proposed standards for improving existing buildings: Case of UK, USA and India

22 Status of energy standards in 81 countries in 2009 Source: Janda, K (2009) Worldwide status of energy standards for buildings: a 2009 update ECEEE 2009 conference. 1-6 June 2009, France. UK: Standards for domestic buildings Three main energy and CO 2 standards for buildings in the UK: 1. Energy Saving Trust s Standards 2. Passivhaus 3. Association of Environment Conscious Building (AECB) standards AECB Energy standards applied to a typical dwelling Standard Gas, oil or LPG (kwh/m 2 yr) Electricity (kwh/m 2 yr) CO 2 emissions ( kg/m 2 yr) Average of UK dwelling stock UK Building Regulations ADL Silver Gold Domestic sector figures based on an 80m 2 semi-detached dwelling.

23 UK: Standards for office buildings USA: ASHRAE standards ASHRAE standards focus primarily on the building shell and/or the HVAC and in commercial buildings also on lighting and water heating. Latest is ASHRAE Proposed ASHRAE Standard d 189.1, 1 Standard d for the Design of High-Performance Green Buildings Except Low-Rise Residential Buildings. Attempting to establish energy efficiency at 30% below the ASHRAE performance levels and mandates use of renewables. ASHRAE s proposed building energy labelling programme: provide motivation for reducing energy use in commercial buildings. Environmental Protection Agency (EPA) has developed: Energy Star Target Finder (designed to establish energy budgets for new buildings) Portfolio Manager (designed to track energy performance of existing buildings).

24 USA: 2030 Challenge targets U.S. Average Site Energy Use and 2030 Challenge Energy Reduction Targets (CBECS 2003) Primary space / building Available Average Average Average Site 2030 Challenge Site EUI Targets (kbtu/sq.ft./yr) type in target Source EUI percent EUI 50% 60% 70% 80% 90% finder (kbtu/sqft/yr) electric (kbtu/sqft /yr) Target Target Target Target Target Administrative/ professional & government office * Bank * Clinic/ other outpatient % health College / university (campus level) % Hotel, motel or inn * K-12 School * Nursing home/ assisted % living Public assembly % Self- storage 12 44% Supermarket/ Grocery * Residential space/ building type Single family detached Single family attached Multi-family 2-4 units Multi-family 5 or more units Mobile homes India: Proposed standards by Bureau of Energy Efficiency Table of BEE Star rating for Office Building more than 50 % Air Conditioned Built-up Area Climate Zone - Composite AC building in Composite climate ear) EPI (kwh/sqm/ye below Star 2 Star 3 Star 4 Star 5 Star Star Label kwh/m 2 /annum /year EPI (kwh/sqm/year) Non-AC building in Composite climate Table of BEE Star rating for Office Building less than 50% Air Conditoned Built-up Area Climate Zone - Composite below 40 1 Star 2 Star 3 Star 4 Star 5 Star Star Label kwh/m 2 /annum /year

25 Energy consumption for Cooling: Offices kwh/m2/y) Energy Consumption for Cooling (k 300 Single Glazed Tower (7 70 s) 210 Double Glazed Tower (90 s) Insulated S.G. (8 80 s) 50 Insulated SD.G. (90 s) 40 esign. (90 s) Low Energy D 15 Passive Office. (90 s) 5 (Source: Professor Mat Santamouris, University of Athens, 2007) Reducing energy use and CO 2 emissions from existing buildings: Case of UK, USA and India

26 Life cycle energy use in a typical new house LIFEYCLE ENERGY USE, NEW HOUSE 4% Embodied energy Elec. for lighting and appliances Gas for heating and cooking 30% 66% NOTE: For a 160m 2 detached house built to Part L of the 2002 Building Regulations and assuming that energy use for space heating matches the design predictions. Calculated over a lifecycle of 100 years. Key principles: energy efficiency and carbon intensity Reduce the demand for energy (heating, cooling, lighting or ventilation). Provide the reduced demand through low-carbon and zero-carbon technologies. Decarbonising the electricity supply. Feedback on actual energy used in buildings through smart metering. Regular post-occupancy evaluation studies of refurbished projects to provide evidence-based lessons for the building community and users.

27 Strategies for CO 2 reduction from existing buildings Space heating Water heating Typical end uses of energy in a building Space cooling Lighting Appliances Demandside energy efficiency measures CO2 reduction strategies to address different end uses of energy in an existing building Roof insulation Hot water tank insulation CFLs Wet appliances Cavity wall insulation Primary hot water pipe insulation Energy efficient fittings Washing machines Solid wall insulation: internal Movable shading: awnings, window shutters Tumble dryers Solid wall insulation: external Permanent shading: louvers, overhanging eaves Dishwashers Floor insulation Glazing: proportions of solar heat transmission White appliances Low-e double glazing Using building materials that store heat. Refrigerators Draught stripping Using large areas of thermal mass Fridge-freezers Installation of a condensing boiler Improved controls Keeping the thermal mass exposed Displacement ventilation Night-storage cooling Use of fans for localised body cooling Using efficient electrical appliances Freezers Brown appliances Video recorders Televisions Electric ovens Electric hobs Supply-side measures Low carbon systems Biomass heating Micro-CHP Heat pumps Solar air conditioning Renewables Sunspace/Conservatory Solar hot water Solar PV Micro-Wind turbine Micro-hydro Potential for CO 2 reduction in UK domestic stock Cost-effective energy efficiency measures: >20% reduction in CO 2 + Advanced glazing and micro-generation: >60% reduction in CO 2

28 UK Govt study: Potential for CO 2 reduction in UK domestic stock Potential for CO 2 reduction in US building sector (Source: McKinsey, 2007)

29 Managing energy use and CO 2 emissions: policy instruments Case of UK, USA and India Policy instruments for reducing CO 2 emissions

30 Control and regulatory instruments: UK, USA and India Information and voluntary instruments: UK, USA and India

31 Policy instruments in developing countries Regulatory policies such as appliance standards and building codes are found to be more effective if properly enforced. Economic and market-based instruments - not been employed much due to low level of baseline energy data availability. Financial instruments: Taxation on CO 2 or household fuels are not frequently used. Tax exemptions to introduce new technologies and also help poor households to engage in energy efficiency investments. Information and voluntary instruments are important as lack of information has been identified as major barrier. Generally, the first energy efficiency policy measures to be employed. Cross-fertilisation of new-build and refurbishment (Source: Dr David Strong, Inbuilt consulting, 2008)

32 Conclusions and Recommendations Main conclusions Comparatively evaluated building-related CO 2 measurement, benchmarking and reduction approaches available in US, UK and India: shared lessons learnt. UK is world-leading in its CO 2 reduction policy for buildings, but lacks good-quality bottom-up data sets of real building energy consumption and emissions. US on the other hand, has excellent data sets by EIA and DoE, but needs to have national-level policies and targets for CO 2 reduction from buildings. India is working on both policy and data collection given that the energy data is quite polarised between the urban and rural. Large potential to learn from each other

33 Key recommendations Although technologies have been greatly advanced, a lack of accurate information exists about impact of occupant behaviour introduces to building s energy consumption. More work is required in this area. Regularization of data collection and analysis: Lack of consistent data which makes it difficult to understand the underlying changes that affect energy consumption in buildings. Given the lack of empirical data for real performance of buildings, there is a need for extensive nationwide monitoring campaigns to plan decarbonising strategies properly and to assess their impact. Low carbon future: a reality : living on the planet as if we intended to stay Thank you! Humanity Forward