A Critical and Comparative Evaluation of Co 2

Transcription

1 CHAPTER3 A Critical and Comparative Evaluation of Co 2 Emissions From National Building Stocks of Developed and Rapidly-Developing Countries Case Studies of UK, USA, and India Rajat Gupta* and Smita Chandiwala 1. INTRODUCTION In 2002, buildings were responsible for 7.85Gt, or 33% of all energy-related CO 2 emissions worldwide (Price et al. 2006), and these emissions are expected to grow to 11Gt or 15.6Gt by 2030 (IPCC 2007), the two figures are based on different projected scenarios. In developed countries such as the United States and the United Kingdom, energy use in the building stock is responsible for about 50% of national CO 2 emissions (Mazria and Kershner 2008; DOE 2006; EPA 2003). Yet most efforts nationally and internationally have focused on improving the performance of new buildings (WEC 2004). The UK has set a target of making all new domestic buildings zero carbon by 2016 and all new non-domestic buildings zero-carbon by 2019 (DCLG 2006). Similarly, in the US the Architecture 2030 campaign calls for the fossil-fuel reduction standard for all new buildings to be increased to 60% in 2010, 70% in 2015, 80% in 2020, 90% in 2025 and carbon neutral by 2030 (Mazria and Kershner 2008). Similarly, the Building Energy Code in India is currently voluntary and applicable for new commercial buildings or building complexes that have a connected load of 500kW or greater, or a contract demand of 600KVA or greater (Bureau of Energy Efficiency 2006). *Corresponding author: rgupta@brookes.ac.uk 74

2 CHAPTER 3 75 Given that about two-thirds of existing buildings will be standing in 2050, targeting new buildings only limits the increase in CO 2 emissions. To reduce CO 2 emissions in the longer-term, the existing building stock needs to be targeted (Urge-Vorsatz et al. 2007). The problem with existing buildings is simple: they underperform in relation to current building standards because they were designed and built at a time when sustainability and energy efficiency were not the imperatives that they are today. To put this in context, a typical UK house built in 1910 emits in the region of eight tonnes of CO 2 per annum, and a house built in 1995, four tonnes per annum. The existing building stock in both developed and developing countries offers a sector where reductions in emissions could be achieved rapidly through technical, educational and other means, leading to more comfortable environment with lower fuel bills (Bordass et al. 2001). According to the Fourth Assessment Report of the IPCC (2007), approximately 29% of CO 2 emissions can be saved economically, or at a net benefit to society, even at a carbon price of zero. The opportunity for very substantial investments into improving the existing building stock has opened up as the housing markets in the UK, USA and several other developed countries have gone into deep and prolonged recession. Mitigation measures in the residential and commercial sectors can save approximately 1.6 billion and 1.4 billion tons of CO 2 emissions respectively by 2020 (Urge-Vorsatz et al. 2007a). While the magnitude of these large potentials that can be captured has been known for decades, many of these energy efficiency possibilities have not been realized. This is because of certain characteristics of markets, user behaviour and a lack of critical evaluation of the available tools and models that could be used by planners, building designers and policy-makers to measure, benchmark, target, plan and monitor energy-related CO 2 emissions and forecast reductions from existing buildings. This paper aims to address this gap by undertaking 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 in developed and rapidly-developing countries using case studies of the UK, USA, and India. The specific objectives are as follows: Establish what tools, approaches and methodologies are available for measuring energy use and CO 2 emissions from existing buildings in UK, USA and India. Review and compare benchmarks of annual energy consumption intensities (kwh/m 2 /year) and CO 2 emissions (kgco 2 /m 2 /year) from buildings-in-use in the case study countries. Develop more rigorous standards for existing buildings (to reduce their energy consumption), which could be adopted by developed and rapidly-developing cities taking account of building type, local climate and occupancy.

3 76 CITIES AND CLIMATE CHANGE Evaluate various strategies and measures available for maximizing CO 2 emission reductions in existing buildings (above 80% in developed countries) through improved energy-efficiency, low and zero carbon technologies, as well as non-technical solutions (education and awareness, behavioral change), and to identify barriers to their implementation. Recommend policy measures which would increase uptake of the selected CO 2 reduction strategies in existing buildings. 1.1 Overview Of Energy Use and CO 2 Emissions in the Global Building Stock Globally, energy (delivered) use in the built environment, which encompasses domestic (residential) and non-domestic buildings, will grow by 31% over the next 20 years, at an average annual rate of 1.5%, according to International Energy Outlook (EIA 2006). In 2030, consumption attributed to domestic and non-domestic sectors (commercial) will be approximately 67% and 33% respectively. Industrial energy use is not considered as part of the buildings analysis in this paper. The growth in population, increasing demand for building services and comfort levels, together with the rise in time spent inside buildings, assure that the upward trend in energy demand will continue in the future. Economic, trading and population growth in rapidly-developing economies will intensify needs for education, health and other services, together with the consequential energy consumption. It is expected that energy consumption in the non-domestic building sector in developing countries will double in the next 25 years, with an annual average growth rate of 2.8% (Pe rez-lombard et al. 2008). CO 2 emissions from the building sector are predominantly a function of energy consumption and may be either direct (on-site), such as emissions from fuels combustion, or indirect, such as emissions from electricity use and district heat consumption. More recently, studies are also including embodied energy of materials for building construction e.g, cement or concrete. Certain energy end-use activities such as cooking, air-conditioning, space heating and refrigeration may generate either direct or indirect emissions depending on the technology used (Baumert et al. 2005). Broadly, emissions from buildings can be organized into three broad categories: electricity use, direct fuel combustion, and district heating (Figure 1).

4 CHAPTER 3 77 FIGURE 1 CO 2 from Building Energy Use Source: Baumert et al Electricity use includes lighting, appliance use, refrigeration, air conditioning, and to some extent, space heating and cooling. These activities account for 65% of commercial building emissions and 43% of residential building emissions (Figure 1). Globally, the building sector including residential and commercial is responsible for more electricity consumption 42% than any other sector. Direct fuel combustion results primarily from space heating with modest contributions from food preparation (gas-driven cooking) as well as gas-driven air conditioning and refrigeration systems. This source accounts for 45% and 31% of emissions in residential and commercial buildings, respectively. District heating includes centrally-operated heating (and sometimes cooling) systems that service entire cities or other large areas. Emissions from the building sector vary widely by country in both absolute and per-capita terms (Figure 2), and depend greatly 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.

5 78 CITIES AND CLIMATE CHANGE FIGURE 2 CO 2 from Building Energy Use, Total and Per Capita in 2002: Top 25 Emitters Source: IEA 2004a, 2004b Within the building sector, it is important to distinguish between domestic (residential) and non-domestic buildings. The non-domestic (service) building sector, which covers all commercial and public buildings, includes many types of buildings (schools, restaurants, hotels, hospitals, museums, etc.) with a wide variety of uses and energy services (HVAC, domestic hot water (DHW), lighting, refrigeration, food preparation, etc.). The type of use and activities have a huge impact on the quality and quantity of energy services needed in non-domestic buildings. By and large, dwellings in developed countries use more energy than those in emerging economies and it is expected to continue growing due to the installation of new appliances (air conditioners, computers, etc.) 2. ENERGY USE AND CHARACTERISTICS OF EXISTING BUILDINGS IN UK, USA AND INDIA 2.1 Existing Building Sector in the UK Energy use in the buildings sector alone generates almost half of all CO 2 emissions in the UK 27% from the 26.4 million residential dwellings, and 18% from the two million non-domestic buildings (including commercial, public sector, and industrial building use) (All Party Urban Development Group 2007; Pout and MacKenzie 2005). To assess the potential for CO 2 emissions reductions from the UK building

6 CHAPTER 3 79 stock, the energy performance and characteristics of domestic and non-domestic sectors should be characterized, as discussed in the following sub-sections Domestic Building Sector In the UK, a major use of energy within the built environment is for heating. Gas currently meets more than two-thirds of this demand through the nationwide gas grid. Heating is a particularly important part of energy use within homes and hence a major contributor to CO 2 emissions from the domestic sector (Foresight 2008). As a guideline, household energy consumption is in the range of 21-22,000 kwh a year, for all energy use in the home, from all sources of fuel (Boardman 2007b, p. 4). Of this, roughly 60% is for space heating, 21% for hot water and 13% for lights and appliances (Figure 3). FIGURE 3 UK Household Energy Consumption by End Use Consumer electronics 3% Cold appliances 3% Cooking 3% Lighting 3% Miscellaneous 2% Wet appliances 2% Hot water 21% Space heating 60% Source: DEFRA 2007; SDC 2006 Proportions of CO 2 emissions from various activities in housing are shown in Figure 4, which shows that the major portion of energy consumption is in space heating and hot water (81%). However, the proportion of CO 2 emissions from those uses is less (74%) due to the lower carbon content of gas compared to electricity. Over the long term, energy demand has grown fastest from appliances, with energy for heating remaining largely stable, although recent changes are much smaller (CLG 2006).

7 Consumer electronics 6% 80 CITIES AND CLIMATE CHANGE FIGURE 4 UK Household CO 2 Emissions by End Use Wet appliances 4% Lighting 5% Cold appliances 5% Miscellaneous 3% Cooking 3% Hot water 21% Space heating 53% Source: DEFRA 2007; SDC 2006 Energy performance of domestic buildings in the UK is measured using the Standard Assessment Procedure (SAP), which measures the fuel efficiency of the heating systems and thermal efficiency of the building fabric i.e. how well it retains heat (BRE 2005). The average SAP of the 2004 stock was 52. Energy performance varies widely across the domestic stock. The factors that have the greatest correlation with energy performance of the existing stock are age and dwelling type/ size. Modern properties are much more energy efficient and smaller properties suffer less heat loss. Apart from these more or less immutable factors, the quality and amount of insulation and efficiency of heating systems also affect energy performance (CLG 2006). Other factors that are taken into account in the SAP calculations include building shape, orientation, window sizes and distribution. The 2009 edition of the Standard Assessment Procedure (SAP 2009) was introduced in October 2010 (BRE 2010). A step change in the energy efficiency of post-1990 stock, since implementation of Part L of the Building Regulations, has progressively raised the energy efficiency standards for new homes. Improvements in the energy performance of new build, combined with household improvements, have led to an increase in the average energy efficiency of the stock. Two-thirds of all properties have SAP values between 41 and 70. There is a clear trend of older properties having much lower energy performance: over 40% of properties built before 1919 have SAP values of less than 41 (Figure 5). By contrast, 60% of properties built since 1990 have SAP ratings above 70.

8 CHAPTER 3 81 FIGURE 5 Profile of Energy Performance of Existing Domestic Stock in UK, 2004 Source: CLG, 2006 The total energy consumption in the domestic stock also depends upon the number of households and population. Of the 26.4 million dwellings in the UK in 2006 (CLG 2008a), 31% consist of one-person households. This figure is projected to increase to 38% or nearly 10 million one-person households in Such a shift in household size would have significant implications for how energy is used in homes. At the same time, the UK population is expected to increase to 67 million by 2050 and net migration to the UK is projected to continue. The effect of this growth is compounded by declining household size in 2002, the average household contained 2.3 people, and it is assumed that this will drop to 2.1 people per household (pph) by There has also been an increase in expectations of material comfort over the past century. Desired temperature levels within the home have increased from 12 C in 1970 to 18 C in 2002, with consequent impacts on energy consumption.

9 82 CITIES AND CLIMATE CHANGE Non-domestic Building Sector Non-domestic buildings (primarily commercial and public) account for about one-sixth of the UK s total CO 2 emissions and one-third of the building-related ones (Committee on Climate Change 2008). Figure 6 shows the split of CO 2 emissions within the non-domestic sector, which indicates that the retail sector is the major contributor, followed by hotels and catering and warehouses (Pout and MacKenzie 2005). FIGURE 6 UK Non-domestic CO 2 Emissions by Sub-sector in 2002 (Source: Pout and MacKenzie 2005) Figure 7 shows the breakdown of CO 2 emissions by end use and by fuel type in the non-domestic sector. In terms of end use, it is clear that heating contributes the most at 37%, followed by lighting at 26%. In terms of emissions by fuel type, electricity contributes the most, followed by gas, since the carbon emission factor of electricity in the UK (1kWh of grid electricity = kg CO 2 ) is about three times more that gas (1kWh of natural gas = kg CO 2 ) (Pout and MacKenzie 2005). FIGURE 7 UK Non-domestic CO 2 Emissions by Sub-sector in 2002 (Source: Pout and MacKenzie 2005)

10 CHAPTER 3 83 Accurate data on total energy use in the non-domestic stock are not available, but estimates suggest that electricity consumption amounted to about 95GWh in 2004 and gas consumption to about 85GWh (Foresight 2008). Over , CO 2 emissions from commercial buildings grew by 4%. This was primarily due to a 6% rise in indirect (electricity-related) emissions, with electricity demand growth more than offsetting the declining carbon intensity of electricity. Public sector emissions fell 26%, wherein direct emissions fell due to energy efficiency improvements in heating and a switch to less carbon-intensive fossil fuels. Indirect emissions fell as the declining carbon intensity of electricity more than offset rising electricity demand (Committee on Climate Change 2008). The total floor space of commercial and industrial bulk class properties in England and Wales was 597 million square meters in 2007, 6% more than in 1998 (Foresight, 2008). Although there is a statistical evidence base covering all recorded property types, drawn from the Valuation Office Agency database (Ravetz 2008), this covers hereditaments, floor spaces and rateable values; but not conditions, construction or other finer detail. A major effort was made by the then Global Atmospheric Division of DETR, to develop a national Non-Domestic Building Stock (NDBS) database (Bruhns et al. 2000). One result was the National Non-domestic Buildings Energy and Emissions Model (N-DEEM), which was used to model energy policy impacts (Pout, 2000). There may be more activity on this front in the future, as the energy performance of new and existing property is now emerging as a priority (CLG and UKGBC 2007). The non-domestic stock is somewhat more modern than the housing stock. Nevertheless, as seen in Figure 8, just over half of all commercial and industrial properties were built before 1940 and only 9% after 1990 (CLG 2005a; CLG 2005b). Just over a quarter of commercial building space by area was built before 1940 and only 15% since 1990 (Figure 9). FIGURE 8 Age Profile Hereditaments on the Non-domestic Sector by Bulk Class Source: Foresight 2008

11 84 CITIES AND CLIMATE CHANGE Programmes for Achieving CO 2 Reductions from the Existing Building Sector in the UK The European Commission is providing a complex framework for carbon reductions in the domestic sector the requirement is to reduce CO 2 emissions by 20% and to have 20% of all energy from renewable sources, both by 2020, for the whole of Europe (Boardman 2007b). In line with this, the National Energy Efficiency Action Plan (NEEAP) set a target to reduce emissions from the UK s residential housing stock to MtCO 2 (a 31% reduction) by 2020 (DEFRA 2007). In February 2009, the UK Government launched a consultation on the Heat and Energy Saving Strategy (HESS), which sets out an aim for emissions from existing homes to be approaching zero by 2050 (DECC 2009c) in order for the UK to achieve its ambitious target of an 80% cut in emissions by Figure 9 summarizes the CO 2 emissions saved as part of these targets and programmes discussed. FIGURE 9 Summary of UK Residential Sector Emissions Targets (MtCO2e) Source: Centre for Sustainable Energy et al. 2006

12 CHAPTER 3 85 To support HESS, the Government has set out the following key policy proposals: Provide the capacity to deliver comprehensive, whole-house solutions to 400,000 homes a year by By 2020, extend the delivery of whole-house solutions to approximately 7 million homes across the UK. Be on the way to making cost-effective energy efficiency measures available to all households by These new ways of using energy in UK homes require a new approach to delivering the policies. The current delivery model, the Carbon Emissions Reduction Target (CERT) has seen energy suppliers under an obligation set by the Government to achieve certain emissions reductions (DECC 2009a). However, beyond this a more coordinated, community-based approach is used, working door-to-door and street-to-street to cover the needs of the whole house. The proposed new Community Energy Savings Programme (CESP), to be launched this year, will be a pilot for this more coordinated approach (DECC 2009b). In the meantime, the following policy drivers continue to target energy use in UK homes (CLG 2006). The Government already has a legal obligation to ensure that people are not living in fuel poverty 1 by 2016, which is caused by a combination of poorly insulated, energy inefficient housing and low incomes. There were 3.5 million households in fuel poverty in 2006 and this figure increased to 5.5 million in 2009 (DECC,2011; Fuel Poverty Advisory Group 2008). Clearly, cutting CO 2 emissions through energy efficiency in UK homes can help in tackling fuel poverty, a long-standing problem for vulnerable groups in UK especially the elderly. Decent Homes: The Government s aim is to make all council and housing association housing decent by 2010 by improving the condition of an existing home to one that is warm, weatherproof and with reasonably modern facilities. It is not intended specifically to improve energy efficiency but, by including a thermal comfort criterion, it is expected to have a significant effect on the energy performance of those homes. In 2006, 37% of all housing was defined as non-decent according to current standards (Foresight 2008). Warm Front: Government s main grant-funded programme for tackling fuel poverty, launched in June The scheme fits packages of measures including insulation and heating systems. Grants of up to 2,700 are offered for families and the disabled and a grant of up to 4,000 where the work approved is 1 A household is in fuel poverty if in order to maintain a satisfactory heating regime it would be required to spend more than 10% of its income (including Housing Benefit or Income Support for Mortgage Interest) on all household fuel use.

13 86 CITIES AND CLIMATE CHANGE installation of an oil-fired central heating system. Carbon emission reductions under Warm Front and other fuel poverty programmes are expected to be 0.4MtC a year by 2010; Energy Performance Certificates (EPCs) which are required on sale or rent of buildings. They give potential buyers/tenants information on the current performance of a house and its cost-effective potential, setting out the costeffective measures relevant to the property; Building Regulations: If building work is being carried out on existing buildings, building regulations are likely to apply. This covers work from building an extension to replacing windows or the boiler. Part L of the building regulations sets standards related to the conservation of fuel and power. The key policy affecting energy and CO 2 performance of non-domestic buildings is the Energy Performance of Buildings Directive (EPBD), part of European legislation that all member states must adopt. Measures set out by the Directive include the following (CLG 2008c): Introducing energy performance certificates (EPCs); Requiring public buildings to display energy certificates (DECs); and Requiring inspections for air conditioning systems. Under the Directive, since October 2008 all buildings homes, commercial and public buildings when sold, built or rented require an Energy Performance Certificate (EPC). The certificate provides energy efficiency ratings on a scale from A to G and recommendations for improvement. The ratings are standard, so that energy efficiency can easily be compared across different buildings of similar type (CLG 2008c). Since October 2008 Display Energy Certificates (DECs) are also required for larger public buildings over 1000m 2, so that everyone can see how efficiently public buildings are using their energy. It is widely known that there is a gap between buildings energy performance by design (EPCs) and how they actually operate (DECs). Therefore, both EPCs and DECs are needed in order to have a holistic picture of a building s energy performance (CLG 2008b). On 19 May 2010, a recast of the Energy Performance of Buildings Directive was adopted by the European Parliament and the Council of the European Union in order to strengthen the energy performance requirements and to clarify and streamline some of the provisions from the 2002 Directive it replaces. One of the main highlights of the Recast EPBD for existing buildings is that member states shall develop policies and take measures (such as targets) in order to stimulate the transformation of buildings that are refurbished into very low energy buildings (European Commission, 2010).

14 CHAPTER Existing Building Sector in the USA Energy use in the United States (US) rose by almost 50% from 1970 to This growth has come through oil, coal and nuclear energy, although the contribution of gas has not changed much (EIA 2008b). Oil was the largest source of energy in 1970 and still is. Renewable energy provided 6% of energy needs in both 1970 and The decreasing importance of natural gas and the increasing use of coal in the energy mix (especially for electricity generation) is one of the factors underlying the increasing CO 2 emissions (Hillman et al. 2007). This is in marked contrast to the UK, where the use of coal, especially in power stations, has dropped sharply and its replacement with natural gas has consequently reduced CO 2 emissions. Changes in the proportion of total (final) energy used by different sectors of the economy since 1970 are shown in Figure 10. Although energy use by industry has become less important, commercial energy use has risen by more than half and residential energy use has gone up by a sixth (EIA 2008b). FIGURE 10 Changes in the Proportion of Final Energy Demand by End-Use Sector from 1949 to Source: EIA 2008b Data from the US Energy Information Administration (EIA) distributes the various elements of the building sector into several sectors, i.e. industry, commercial, residential, transportation and so on. The proportion of final energy demand by the different sectors in 2007 was: Residential: 21% Commercial: 18% Transportation: 29% Industrial: 32%

15 88 CITIES AND CLIMATE CHANGE To determine the real energy impact of buildings, Architecture 2030 has combined these various elements into a single sector called Buildings (Mazria and Kershner 2008; Mazria and Kershner 2009) 2. Using data drawn from the EIA, it is seen that buildings are responsible for almost half (48%) of all energy consumption and GHG emissions annually; globally the percentage is even greater. Seventy-six percent (76%) of all power plant-generated electricity is used just to operate buildings. The annual embodied energy of building materials and the energy used to construct buildings is estimated at MBtu/sf of building for new construction and half of this for renovation. Residential, commercial and industrial building operations consume 76% of total US electricity generation (Mazria and Kershner 2008). When building-related energy use (residential, commercial and industry building use) is split by end use, it is seen that space heating and space cooling are the major energy requirements (Table 1). However lighting becomes as significant as space heating when CO 2 emissions by end-use are presented, since electricity has a large CO 2 emission factor than gas which is typically used for space heating (National Energy Technology Laboratory 2008). TABLE 1 Primary Energy and CO 2 Emissions in the US Building Stock End Use Residential Commercial Total Building Stock Primary Energy % CO 2 Emissions % Primary Energy % CO 2 Emissions % Primary Energy % CO 2 Emissions % Space heating Space cooling Water heating Lighting Cooking Wet clean Refrigeration Electronics Computers Other Adjust to SEDS Ventilation To create a US Building Sector percentage for the year 2000, the Residential buildings (operations) sector (20.4 QBtu), Commercial buildings (operations) sector (17.2 QBtu), Industrial sector - buildings operations (2.0 QBtu) and the Industrial sector annual building construction and materials embodied energy estimate (8.57 QBtu) were combined. Total annual 2000 Building Sector consumption was QBtu and the total annual 2000 US Energy consumption was QBtu. (Source: US Energy Information Administration annual energy review)

16 CHAPTER Residential Sector Overall energy use in the residential sector has increased since Currently, the residential sector in the U.S. uses approximately 21 EJ (20 Quads) of site energy per year; this amounts to approximately 21% of all energy use in the nation (Parker 2009). In 2006, the residential sector consumed 37% of all electricity produced in the United States, making it the largest consuming sector of electricity (National Energy Technology Laboratory 2008). Average annual energy expenditures per household have increased by 20 percent from For every 1kWh used in the residential sector, another 2.18 kwh is needed to produce and deliver the electricity. The average price of electricity for residential consumers in 2006 was 10.4 cents per kwh (National Energy Technology Laboratory 2008). Despite technological improvements in refrigerator, furnace efficiency and energy codes improving insulation, many American lifestyle changes have put higher demands on heating and cooling resources. The two-person household in a large home has become more common, as has central air conditioning: 23% of households had central air conditioning in 1978 while that figure rose to 55% by Also, miscellaneous electric end-uses in households since 2000 has been rapidly expanding, largely offsetting efficiency gains in the conventional end-uses of heating, cooling and water heating. Electricity is expected to be the fast growing site energy source for residential consumers averaging a 1% growth rate from 2006 to On-site renewable energy accounted for approximately 3% of all energy consumed in the residential sector. The majority of this energy was derived from wood combustion and was used for space heating. Both the number and size of households influence total energy consumption in the residential sector. In spite of a fall in energy use in an average household, the strong increases in population and household numbers have resulted in a sector-wide increase. The US population has grown considerably and consistently over time: in 1970, the total was just over 200 million and it is shortly to hit 300 million (Hillman et al. 2007). The 1990 to 2000 population increase of 32.7 million at 13% towered over the average of 2.5% for other developed countries. In 2006, there were approximately 113 million households in the US and by 2030, there are expected to be 141 million households (National Energy Technology Laboratory 2008). At the same time, the average size of homes built in the United States has increased significantly, from 139m 2 in 1970 to 214m 2 in 2005 (Parker 2009). Recent electricity shortages in California, growing U.S. dependence on foreign energy supplies with highly volatile oil prices and the greatly expanding threat of global warming underscore the critical need to address the efficiency of US homes. Since the twin energy crisis of the 1970s, first passive solar, followed by super insulation have provided increasingly refined means to improve the energy performance of existing housing.

17 90 CITIES AND CLIMATE CHANGE Commercial Building Sector The following pieces of information give some insight into general trends in the commercial sector (National Energy Technology Laboratory 2008): Floor space devoted to commercial activity totalled 74.8 billion square feet in Commercial floor space is expected to reach billion square feet by In 2006, lighting used 24.8% of primary energy attributed to the commercial sector and produced 25% of CO 2 emissions. This is approximately twice the energy used and emissions produced by space cooling. Lighting accounts for 42% of a commercial building s cooling load. In 2003, the most energy-intensive buildings were those related to food sales using thousand Btu per square foot. The building type with the lowest energy intensity (excluding vacant buildings) was religious worship buildings using 77.0 Btu per square foot. Electricity accounted for 74% of all energy expenditures in the commercial sector. About 80% of all CO 2 attributed to the commercial sector comes from electricity consumption. The average price of electricity for a commercial consumer in 2006 was 9.5 cents per kwh. In 2003, buildings devoted to office space consumed 19% of primary energy attributable to commercial buildings, the most of any building type Programmes for Achieving CO 2 Reductions from Existing Building Stock According to Mazria and Kershner (2008, 2009), the total US building stock equals approximately 300 billion square feet, of which approximately 1.75 billion square feet of buildings is pulled down, 5 billion square feet renovated and 5 billion square feet built annually. This means by 2035, approximately three-quarters (75%) of the built environment will be either new or renovated. Clearly, this transformation over the next 30 years represents a huge opportunity, and immediate action in the building sector is essential if we are to avoid hazardous climate change. To accomplish this, Architecture 2030 issued the 2030 Challenge calling for all new buildings and renovations to be designed so as to reduce their fossil-fuel, greenhousegas-emitting (CO 2 ) energy consumption by 30% below that required by the latest IECC 2006 and ASHRAE code standards, incrementally increasing the reductions to carbon neutral by Apart from improving the fossil-fuel reduction standard of new buildings incrementally every 5 years, 2030 Challenge calls for an equal amount of existing building area to be renovated annually to meet a

18 CHAPTER 3 91 GHG-emitting, energy consumption performance standard of 50% of the regional (or country) average for that building type (Mazria and Kershner 2008). In addition, there are a range of programs and organizations that are working to increase the energy efficiency of existing buildings in the US, as follows: Building America is a ten-year-old industry-driven research program, sponsored by the U.S. Department of Energy. The program has produced new homes on a community scale that use on average 40% to 100% less source energy. The program also increases the energy efficiency of existing homes by 20-30% (DoE 2004). Lessons learned by one builder are rapidly shared with other builders throughout the Building America community leading to improved building performance at no added cost. The ENERGY STAR program was established by the U.S. Environmental Protection Agency (EPA) in 1992 for energy-efficient computers. The ENERGY STAR program works with manufacturers to promote existing energy-efficient products and develop new ones. Manufacturers can affix an easily visible label to products that meet Energy Star minimum standards (EPA 2003). The program has been a success and extended to include numerous other electrical appliances such as refrigerators, TVs etc. as well as buildings. The ENERGY STAR Building Program is the most widely used building energy label for existing buildings in the U.S. Developed by the EPA, it makes the energy performance rating available to users through password-protected accounts in a web-based tool called Portfolio Manager. 2.3 Existing Building Sector in India India has emerged, both economically and politically, as one of the key global players. It is already the world s third largest economy growing recently at an average of 8.5% a year, and currently ranks sixth in the world in terms of primary energy demand. Its population has increased from 560 million in 1971 to 1,150 million in 2009, and is expected to be the world s most populous country by 2035 (Planning Commission 2005). The economy is shifting towards services located in urban centres with a growing upwardly mobile middle class. The construction industry in India is growing annually at a rate of 9.2% compared to the global average of 5.5%. It is predicted that by 2020 about 40% of India s population will be living in cities, as against 28% today (McNeil et al. 2008). As a result of the growing economy and rapid urbanization, India has been witnessing continued growth in energy consumption. This trend has already begun to strain the power sector with energy shortages. The Central Electricity Authority (CEA) has estimated that the country is currently facing electricity shortage of 9.9% and peak demand shortage of 16.6% (CEA 2009). There are

19 92 CITIES AND CLIMATE CHANGE varied energy consumption patterns in different zones in India. The economically prosperous states of Gujarat, Punjab, Maharashtra, etc., show a high-energy consumption pattern. Per capita electricity consumption stood highest in Punjab (861kWh), followed by Gujarat (724 kwh) and Maharashtra (594kWh) against the national average of 360kWh (Statistical Abstract 2001). The poor regions of the Northeast, on the other hand, have a very low consumption of energy ranging between 75 and 185kWh, much lower than the national average. The building sector in India is currently the second largest consumer of energy, and building energy use is increasing by over 9% annually, which greatly outpaces the national energy growth rate of 4.3% (USAID and LBNL 2006). Figure 11 shows the electricity consumption of various sectors in India (CEA, 2009). FIGURE 11 Electricity Consumption by Sector in India Source: CEA 2009 Since the building sector (domestic and commercial) accounts for approximately 33% of electricity consumption and is the fastest growing sector, it is critical that policies and measures are put in place to improve energy efficiency in both new construction as well as existing buildings. In fact it is estimated that 70% of building stock in the year 2030 is yet to come up in the country - a situation that is fundamentally different from developed countries such as the UK and US (Kumar et al. 2010) Residential Building Sector Residential energy consumption (excluding traditional biomass) per capita rose the fastest in India, compared to China and the US (CMIE 2001; Reddy and Balachandra 2006). A switch from traditional biomass to modern fuels, and the increased use of modern fuels by an expanding urban population are driving factors behind this increase (Planning Commission 2005).

20 CHAPTER 3 93 In developing countries such as India, it is important to divide households into rural and urban locales due to the different energy consumption patterns found in these locations. Disparities in household energy use exist between rural and urban populations and also between high- and low-income groups. In rural areas, traditional fuels, such as fuelwood, charcoal and agricultural waste, constitute a major portion of total household energy consumption, while in urban areas households use kerosene, electricity and LPG (Reddy and Balachandra 2006). According to analysis by LBNL, electricity consumption per urban household will increase from 908kWh in 2000 to 2972kWh in 2020 (LBNL 2009). The type of end uses for energy consumption in urban residential buildings is shown in Figure 12. Lighting accounts for 28% and air conditioning for 7% of the total electricity consumed in the sector. Approximately 13% of the electricity consumed is in refrigerators. FIGURE 12 Energy Consumption in the Indian Residential Sector, 116 Billion Units Source: Bureau of Energy Efficiency 2006b Energy use for air conditioning is a growing concern, as the rising middle class in India is in the process of making the transition into an energy-intensive way of life. Their new lifestyle aspiration for air conditioned comfort, being met readily by what is now on offer off the shelf from the air conditioning industry, will become the largest cause of and contributor to increased energy consumption. The challenge and the opportunity of this transitional situation is to find those alternatives to meet legitimate aspirations for better comfort that are inherently less capital intensive as well as less energy intensive.

21 94 CITIES AND CLIMATE CHANGE Commercial Building Sector Electricity is a major energy form used in the commercial sector in India. Electricity use in this sector has been growing at about 11-12% annually, which is much faster than the average electricity growth rate of about 5-6% in the economy (Bureau of Energy Efficiency 2006b). Approximately 60% of electricity used in the commercial sector is consumed in lighting and 32% in space conditioning (as opposed to 7% in residential) (Bureau of Energy Efficiency 2006b). In other words, in the case of commercial buildings the threshold into air conditioning dependency has already been crossed and it would be very difficult to reverse the trend. Whereas in the case of residential buildings there is still the opportunity and potential of prevention (Lall 2008). When this large urbanizing population crosses the threshold into a culture of air conditioned comfort in the home the impact on energy consumption will be severe. As one shifts from circulating fans and evaporative coolers to an air conditioner, the peak demand of electricity increases by six to ten times per unit of conditioned space an increase of about 90 watts per square meter of conditioned space (Lall 2008). This is even more important since it is estimated that while the building sector as a whole is poised to grow at a rate of 6.6% annually up to 2030, the commercial sector is currently growing at a rate of 9% per year. A recent study by McKinsey (2009) has estimated that by 2030 the built-up area is projected to increase from one billion square meters to four billion square meters for the commercial sector and from eight billion square meters to 37 billion square meters for the residential sector. Notably, 50% of the new construction is taking place in the public sector, which offers the Government a tremendous opportunity to lead by example in adopting energy-efficient practices Programmes for Improving Energy Efficiency in the Indian Building Stock Building Energy Efficiency is emerging as a priority area for the Government of India considering the growth that is taking place in the Indian building sector. Not only will it help in the government s climate change mitigation efforts, but it will also help reduce the widening gap between the supply and demand of power. In a major impetus to institutionalize energy efficiency in the country, the Government of India enacted the Energy Conservation Act in Under this Act, the government established the Bureau of Energy Efficiency (BEE) in March 2002, as a statutory authority under the Ministry of Power (MoP). The BEE s role is to enact and enforce energy efficiency policies through various regulatory and promotional measures. BEE estimates the potential for energy saving in the domestic/commercial building sector to be at least 20% (Bureau of Energy Efficiency 2006b). In conventional Indian buildings, energy consumption is

22 CHAPTER kWh/m 2 /year, which can be reduced to 120kWh/m 2 /year by applications of energy efficient building techniques. BEE also developed an energy efficiency Action Plan which focused on various thrust areas which include Energy Efficiency in Commercial Buildings, Energy Conservation Building Code (ECBC), Energy Managers and Energy Auditors Certification Program, and others. These are discussed briefly as follows: Energy Audit of Existing Buildings BEE launched its first energy efficiency programme for existing buildings in Sample studies conducted in a few selected government buildings in Delhi under the programme, have identified energy savings potential of about 30% on average. In the following phase, 17 more buildings in Delhi have been audited. Similar initiatives are being considered for public and private buildings in the states, by the authorities as well as the building owners (USAID ECO-III project 2008a) Electricity Act The Indian Parliament also passed the Electricity Act in It consolidated laws related to generation, transmission, distribution, trade and use of electricity (USAID and LBNL 2006). The Act also mandated the creation of regulatory commissions at the central, regional and state levels. As a consequence, the electric utility system is being unbundled, tariffs are being rationalized, and regulatory commissions are playing an active role in enforcement of bill collection and the promotion of DSM programs in some of the larger states. Under orders from the Maharashtra Electricity Regulatory Commission, for instance, utility companies in Maharashtra have initiated a lighting efficiency program in the residential sector, and the Bangalore Electricity Supply Company has initiated a similar program in Karnataka state. Confederation of Indian Industry Indian industry associations have played an important role in promoting energy efficiency. The Confederation of Indian Industry (CII) and Federation of Indian Chambers of Commerce and Industry (FICCI) are engaged in capacity building through the organization of training programs, workshops, conferences, exhibitions, poster displays, awards, and field visits. The Indian Green Business Centre is an example of an institution created by an industry association; CII jointly with the Andhra Pradesh government and with technical support from USAID set it up as a public private partnership. Its building has acquired the LEED platinum rating. Private ESCOs have mobilized and recently set up the Indian Council for Energy Efficiency Business (ICPEEB) to network, provide input to policy-makers, support business development, and disseminate information on energy efficiency.

23 96 CITIES AND CLIMATE CHANGE USAID s Energy Conservation and Commercialization (ECO) This program has a long history of association with BEE, starting with development of ECBC and continuing with the implementation under the third phase of the ECO program (ECO-III). BEE, USAID, and Asia-Pacific Partnership are actively collaborating under the ECO-III project to help with implementation of Energy Conservation Building Code (ECBC) (Kumar et al. 2010; USAID ECO-III project 2008c), through the following activities: Development of State Level Energy Conservation Action Plans; Assisting BEE in building the capacity of practising architects, building designers, energy auditors/consultants, State Designated Agencies and Municipalities to facilitate ECBC implementation; Promoting technical assistance to enhance energy efficiency in existing buildings and municipalities, and developing a framework of energy benchmarks for commercial buildings in India; Promoting energy efficiency in small and medium-sized enterprises (SMEs); Developing the Energy Efficiency Think Tank to enrich and facilitate energy efficiency policies and programs with active involvement of industry and other stakeholders; Promoting Demand side management (DSM) and Energy Conservation (EC) programs: Developing the Utility/Electricity Regulator driven DSM and EC Programs; Establishment of Regional Energy Efficiency Centers to promote energy efficiency in commercial buildings, domestic appliances, and industrial furnaces in SMEs; Building the capacity of architectural institutions and students in the field of Building Science and Energy Modeling, as a long-term strategy; and Promoting the transfer of energy efficiency experiences, knowledge and best practices between the US and India. 3. MEASURING ENERGY USE IN, AND CO 2 EMISSIONS FROM, EXISTING BUILDINGS IN THE UK, USA AND INDIA A wide range of tools and checklists are available to measure energy use in buildings and improve their energy efficiency while also addressing wider sustainability issues. These can be used at various stages of building design, construction and operation to evaluate if targets are being met, or if they need to be reassessed or redefined.

24 CHAPTER Methodology and Outputs for Energy Measurement Energy assessment tools can be classified based on two main approaches predicted (simulated) data and actual (metered) energy consumption. Energy prediction based on modeling is used to predict energy consumption or carbon emissions using energy models. Models or simulation tools vary in their scope and outputs but on the whole, allow designers to (USAID ECO-III project 2008b): Consider the building as a single integrated system; Predict thermal behavior of buildings in relation to their outdoor environment; Envisage the impact of daylight and artificial light inside the building; Model the impact of wind pattern and ventilation and assess their effect on energy use; Estimate the size/capacity of equipment required for thermal and visual comfort; Calculate the effect of various building components on one another and predict resulting conditions and their impact on energy use; Assess changes in energy consumption through sensitivity analysis with respect to design changes affecting building geometry, materials, components, systems, etc. Energy prediction tools can be further subdivided into three categories: simulation models, correlation tools and scorecard rating tools (Gupta and Chandiwala 2007). I. Simulation models are computer programs that are used to generate a performance prediction from calculations. A modeled scenario is simulated against pre-recorded data typically relating to materials, equipment and climate in order to establish the likely performance and determine the efficiency of a design, for example, BREDEM for domestic buildings in the UK, EnergyPlus in the USA etc. II. Simplified energy models or correlation tools, often referred to as performance-based tools, usually measure a particular element such as energy efficiency or thermal comfort and focus on providing a quick evaluation of a proposed design in the form of a simple indicator. These tools have often been derived from multiple results generated by simulation models, such as SAP for domestic buildings in the UK.

25 98 CITIES AND CLIMATE CHANGE III. Scorecard rating tools provide an assessment where performance is measured through a point-scoring system. Points are achieved by meeting established criteria and the level of compliance determines the performance outcome. Scorecard programs are effectively checklists which focus on a holistic approach and outline intent and requirements. In addition, they also have the potential to incorporate possible design solutions by listing suggested methods to achieve the desired result. Various categories are often weighted depending on perceived importance and local requirements, and the total points are calculated to give a final rating eg. LEED, BREEAM, TERI-Griha. Energy auditing is the second approach which involves collecting actual (metered) energy data for a representative sample of the building stock. Actual energy consumption data will generally be available in quite different forms from that which comes out of design models in general. For a building or premises, actual data is generally only known by fuel. End-uses (heating, cooling, appliances etc) will not be known unless they are specifically sub-metered (CLG and UKGBC 2007). Usually, measuring energy consumption of dwellings is much simpler than that of non-domestic buildings. There are no building services involved, occupancy patterns are similar from dwelling to dwelling, and homes come in broadly similar built forms. By contrast, non-domestic buildings come in all shapes and sizes, they have a range of building services some of them are complex and require careful commissioning and management, and occupancy patterns are varied (All Party Urban Development Group 2007). Both energy prediction and actual energy measurement approaches can lead to three types of outputs, namely: benchmarking, rating systems and energy labeling (Perez-Lombard et al. 2009), depending on the nature and purpose of the expected output. Energy benchmarking refers to a comparison of an Energy Performance Index (EPI) for a range of building types and sizes. Commonly used EPI are energy use per unit area of the building. EPIs can also be based on energy use per occupant, or per bed space in case of dwellings (Perez-Lombard et al. 2009). The benchmarking process generally comprises energy auditing (although it can be combined with prediction tools sometimes) by measuring energy use in existing buildings to create a database of a significant number of buildings. The number of parameters that data is collected for varies widely from one country to another. Benchmarks are generally classified as typical and good practice values and adjusted for climate and sometimes occupancy-related variations so as to be applicable for comparison for a substantial number of buildings. Individual buildings can then be compared to these benchmarks to evaluate their relative energy performance. Benchmarks are an important tool for any country and