Carbon Emissions and the Need for Improved Energy Efficiency

Overview The carbon credibility gap How can it be bridged: renewables vs demand reduction? Where can we reduce our energy consumption Technologies and mechanisms for improved energy efficiency

Targets In response to the increasing body of evidence pointing to global warming the government has signed up to targets for GHG emissions: –Kyoto protocol (ratified 2005) emissions 12.5% below 1990 levels during [DEFRA] Also has aspirations for –18% renewables by 2010, 40% by 2020 [S. Exec] –60% cut by 2050 [SEPN]

Credibility Gap? Are we on target to achieve the 60% target? Equates to a reduction of approx. 90 million tonnes per annum in carbon emissions How do we achieve this?

The Carbon Credibility Gap the emissions gap projected emissions from DEFRA

Bridging the Gap Closing the emissions gap requires action in both energy supply and demand –increased use of energy efficient and renewable sources of energy –and improved energy efficiency resulting in reduced energy consumption

Energy & Electricity Demand 50% of anticipated C savings from energy efficiency [SEPN] Target of 10 MtC per annum by 2010 from energy efficiency (Scotland 1MtC) and 10MtC from the domestic sector alone by 2020 [SEPN] A range of measures implemented to attain this objective: CCL, EEC, updated building regs, etc. Electrical consumption is increasing at 2% per annum & energy consumption increasing at 1% per annum [DTI] Required increase in UK renewables output to meet 15% target: 50 TWh or 425 new 40MW wind farms Potential increase in UK electrical demand with current trends: 90 TWh

Energy & Electricity Demand

Built Environment

Energy efficiency improvements in the built environment will have a major impact on emissions accounts for >50% of delivered energy consumption large scope for energy savings due to poor levels of energy efficiency (particularly domestic sector) built environment can also impact upon transport - 60% of vehicle journeys related to domestic use [S. Exec]

Sector Targets Government GHG emissions targets in energy efficiency are defined in MtC The magnitude of required energy savings kWh will depend upon: –supply mix –performance of other sectors (particularly transport) If transport fails to deliver (e.g. hydrogen fuel) built environment may have to take up the slack What scale of energy savings are required? Scenario based modelling approach is useful...

Example: Domestic Sector Using a simple housing stock model the C emissions for the domestic sector are calculated for the current electricity supply mix and post 2020 mix (0% nuclear, 40% RE, 60% fossil fuel) for the following scenarios: –continuing current trends (increasing heat and electricity demand) –30% reduction in heat demand –30% reduction in heat and electricity demand The desired reduction for carbon from the domestic sector is also shown

Example: Domestic Sector target

Example: Domestic Sector target

Example: Domestic Sector target

Example: Domestic Sector Only through reducing domestic heat and power demand do we achieve any carbon savings Even with 40% renewables but with increasing demand carbon emissions are still greater in 2020!

Achieving Energy Savings How can we bring about the necessary energy savings? –drivers: legislation, planning and cost –mechanisms: better fabric, controls, renewables, design, etc.

Legislation, Planning and Cost Planning –building location –orientation & solar access Legislation –maintenance –insulation levels –component specs –passive solar –integrated renewables –energy monitoring Energy costs

Improved Building Fabric technologies: –advanced glazings and frames, –improved insulation primary benefits: –increased internal temperatures –reduced energy consumption –reduced condensation and dampness –reduced fabric damage from moisture secondary benefits: –improved occupant health potential: 40-80% savings in heating energy consumption [Oliver, 2001]

Improved Systems and Controls technologies: –daylight responsive controls –low energy lighting –occupancy responsive control –condensing boilers –controls and services zoning –variable speed drives benefits –reduced heat and power demand –improved internal conditions potential: –50-90% savings in power consumption with efficient lighting and daylighting control [Knight, 1999] current status –being promoted through CCL

Combined Heat and Power Technologies –gas/diesel fuelled ICE –gas turbine –micro turbines & micro CHP (domestic) Potential –reduces emissions by 10-50% depending upon alternative heat and power sources Current situation –10GW target by 2010 [DTI] –currently hampered by NETA, SRO and poor gas/electricity price differential –reduction in CHP installed capacity since 2001 [CHPA]

Integrated Renewables Technologies –photovoltaics –solar thermal –micro wind turbines Potential –solar thermal can significantly reduce domestic hot water heating requirements –PV and micro-turbines energy potential ~ kWh/m 2 Current situation –42,000 solar thermal systems in UK [STA] –11 MWp of installed PV [IEA]

Integrated Renewables demand data: ECGO 19

Heat Pumps Technology: –ground source heat pumps –air source heat pumps Potential: –newer air source heat pumps potential for 50% reduction in CO 2 emissions [Ustrath] Current situation –very few systems installed in the UK –hampered by gas/electricity cost differential

Emerging Technologies Technologies: –fuel cells –micro-CHP –urban wind power –advanced glazing –etc. Potential –unknown Current Situation –embryonic stage

Technology Costs

Conclusions Reducing energy demand is essential if GHG reduction targets are to be met Renewables alone will not be sufficient Magnitude of reduction in energy requirements will depend upon –supply mix –conversion efficiencies –reductions in other sectors

Conclusions The built environment offers rich potential for energy savings Emissions reductions targets can me met with relatively modest reductions in energy consumption Significant savings can be made with simple measures –improved building design –maintenance –better use of existing technologies

Conclusions A range of energy supply technologies are also becoming available as design options but most are hampered by high cost Hopefully UK energy policy is moving towards a balance of demand and supply measures Only with this balance do we have the possibility of drastically reducing emissions … and only with demand side improvements we can also begin to address our problems of fuel poverty and ill health