40% House

There are substantial opportunities for housing developers, appliance manufacturers, and energy service industries to greatly improve UK housing whilst delivering 60% savings in CO2 emissions services.

In the 40 percent house scenario two-thirds of the carbon emission savings come from demand reduction and one-third from low and zero carbon technologies (LZCs) in homes and local communities.

By 2050, 40 percent house envisages:

• Existing homes are refurbished to a high standard
  
• The worst homes are replaced
  
• All new homes are built to be ultra-low energy homes after 2020
  
• Lighting and appliances energy consumption are reduced by 44%
  
• 54 million low and zero technologies are installed.
  
  

  h4. A demand-side energy focus

  
  

  In terms of energy demand reduction in the domestic sector, there are two main areas to focus on: (1) the building fabric and (2) residential lights and appliances.

  
  

  Improving the building fabric

  
  

  The quality of the building fabric in homes has major implications for energy demand. A long-term strategy to encourage refurbishment across the entire housing stock would deliver major energy savings. Space heating, as the largest consumer of household energy, is a crucial area to address in order to reduce energy demand. The 40 percent house scenario envisages the average space heating demand of the stock being halved. Fabric improvements in existing homes would result in a 40% reduction in space heating whilst newly built homes can be designed to achieve a 90% reduction in space heating.

  
  

  

  
  

  Extensive refurbishment of existing homes is key to the demand reduction strategy because 86% of the 1996 housing stock will still be standing in 2050. There are currently a variety of policy measures for existing homes in the form of grants, advice and accreditation schemes. These include support measures for cavity wall insulation, loft insulation, hot water tank jackets, boiler upgrades, heating controls, and draught proofing. Although all these measures are worth implementing to reduce energy demand, they are not sufficient. Other building fabric improvement measures need to be widely taken up: solid wall insulation, floor insulation, improved air-tightness, heat recovery ventilation and passive cooling (e.g. shutters and blinds to avoid energy-intensive air-conditioning).

  
  

  In the 40 percent house scenario the worst homes are demolished and replaced with new high energy performing homes. In recent years demolition rates have been very low, approximately 20,000 dwellings per annum. At this rate the average house will have to last for 1300 years. The 40 percent house scenario envisages a four fold increase in this low demolition rate, targeting the least fit homes in the housing stock. A targeted demolition programme would be implemented to demolish 80,000 dwellings per annum from 2016 onwards. By 2050, 3.2 million of the worst homes in the housing stock will have been demolished, representing approximately 14% of the 23.9 million dwellings in 1996.

  
  

  
  
  Source: ODPM (2005)

  
  

  The increase in population, the decrease in household size and the need to replace demolished dwellings will create a substantial demand for new houses. From 1996 to 2050 there will be a demand for 10 million additional new homes. Current construction rates are approximately 160,000 dwellings per annum, which is not fast enough to keep up with demand. In the 40 percent house scenario construction rates are increased to an average of 220, 000 per annum over the next 45 years. These homes are ultra-low energy and designed for small household sizes. Design standards like those achieved in the BedZed development, Sutton, need to be the norm for all new housing developments.

  
  

  
  
  Source: ODPM (2005)

  
  

  Improving residential lighting and appliances

  
  

  The 40 percent house scenario allows for an increase in appliance ownership whilst creating a 44% saving in electricity use through the uptake of best available technologies. Therefore, by 2050, the average household’s electricity consumption for lighting and appliances is 1680 kWh per annum in comparison with 3,000 kWh per annum in 1996. Major reductions are achieved for cold appliances and lighting through vacuum insulated panels (VIPs) and LEDs (light emitting diodes). Energy consumption to power consumer electronics is expected to increase, but only allowed to double in the 40 percent house scenario, as manufacturers will fully incorporate energy efficiency into product design.

  
  

  There are many technical opportunities for energy improvements, but there also needs to be a concerted effort by householders to both own suitably sized appliances as well as energy conscious usage. Manufacturers need to be encouraged to view energy-efficiency, as a vital component of product design therefore preventing energy profligate products coming onto the market. Crucially, the 40 percent house scenario envisages the implementation of passive cooling strategies to avoid the need to install air conditioning equipment, which could increase electricity consumption in an unsustainable way.

  
  

  
  
  Source: 1998 data: Fawcett et al. 2000; 2050 data: UKDCM

  
  

  h4. A low and zero carbon (LZC) technology focus

  
  

  A decisive shift to building integrated electricity and heating generation from LZC technologies will achieve a third of the energy and carbon dioxide savings. The 40 percent house scenario foresees almost 54 million LZCs being installed, resulting in over 100 TWh of electricity and 260 TWh of heat generated per annum by 2050. The LZC technology industry will need to grow at a rate of 30% year on year to achieve the deployment of 54 million LZCs. Every dwelling will have an verage of almost two LZCs technologies; this includes solar thermal, photovoltaics, heat pumps, fuel cells, and/or ombined heat and power (CHP), using biomass. CHP integrated at the building and/or the community level will provide 60% of dwellings with heat and electricity. Another 30% of houses will be generating electricity from photovoltaics. A distributed energy system could potentially enable 90% of householders to meet some of their own electricity needs, therefore displacing the need to build new centralised plants, as existing nuclear and coal plants are retired.

  
  

  A complete market transformation to LZC over the course of the next 45 years is possible through taking advantage of the oint when boiler equipment is replaced. Boiler equipment is replaced on average every fifteen years, therefore there are at least three replacement opportunities. LZC technologies require a fundamental shift in capital outlays from centralised utility companies to decentralised energy service companies (ESCos) and consumers.