Energy use in our society is almost always associated with pollution and habitat destruction so all types of energy use are worth looking at:
- While a house is being built
- reducing embodied energythe total amount of energy it takes to make a material (or a building). See more on embodied energy of the building materials
- reducing associated ‘building site’ energy
- During its lifetime
- Upon demolition
Where can the biggest savings be made?
Undoubtedly the main savings are to do with while the house is in use (rather than during construction) and are mainly related to heating and lighting. Particularly the heating and fixed lighting are important because, especially with the heating, it is very difficult to increase the insulation values of the structure after it has been built. It may last for hundreds of years in basically the same state that it was built originally. Items such as electrical appliances and movable lighting are important but tend to get changed every decade or two.
The embodied energy is often cited as being much less important than energy in use (sometimes mentioned as being very roughly a tenth) but that way of looking at it is based on the notion of traditionally very high levels of energy in use. Once you start to reduce the energy in use then the embodied energy starts to take on significance.
The energy associated with building sites has had very little study, especially for self build. It is probably mainly to do with transport costs, which can be relatively high, particularly in the countryside where delivery journeys for materials can be quite inefficient.
Upgrading existing property
This is a much bigger challenge than building from scratch but there are already a couple of examples in the UK of old houses being brought up to PassivhausSee more on the Passivhaus standard. The PassivHaus Institute has pioneered a standard for low energy buildings. It includes very low energy usage and ways of achieving this. The word is derived from the idea of buildings which are fundamentally low energy and passive solar heated rather than using extra gadgets to heat them. See Passivhaus for the UK branch of the organisation. standard: Under the Sun in Birmingham and one in Lambeth, London. Work is more advanced on the continent, particularly in Germany.
The Retrofit for the Future database gives details of dozens of mainly housing association and council properties which are in the process of being brought up to high insulation and air tightness standards. The PDFs go into considerable detail about the methods.
Community energy schemes
There are grants available through the Community Sustainable Energy Programme administered by the BREBuilding Research Establishment. . These cover microgeneration and energy efficiency and are aimed at:
- Reduction in CO2Carbon dioxide is a gas which is given off when carbon based materials such as fossil fuels (coal, oil, and natural gas) are burned. It is called a greenhouse gas because it works like the glazing of a greenhouse and causes global warming emissions
- Increased community awareness of climate change and how changes to our behaviour can reduce it
- Increased skills base of local trades (for example, local builders and building-service subcontractors working on renewable energy projects for the first time)
- Reduction in energy bills
- Reduction in reliance on imported energy and increased independence from commercial energy suppliers
- Stronger partnerships within local communities with lasting social benefits
- Growth of local enterprise in new technologies.
‘Fabric First’ Although waiting for an update (as of 21/10/2012 the guide is based on out of date Building Regsthese are the legal regulations which govern how a house is built. (not to be confused with Planning Permission which is about whether you are allowed to build the house at all or what it might look like) and SAPStandard Assessment Procedure - the method used in the building regulations for calculating the energy use of a house. see Part L and SAP), the ESTEnergy Savings TrustEnergy Savings Trust guide Fabric First contains a great deal of very useful information about the design of a building’s fabric.
The Green Deal'The Green Deal is an innovative financing mechanism that lets people pay for energy-efficiency improvements through savings on their energy bills'. Set to be launched in early 2013 the Green Deal is a way to create energy efficiency improvements in buildings. There will be no up front investment needed by the householder: this will come from the private sector. The householder will then pay for the improvements through increased meter charges based on their energy savings. This will be tied back to their metered energy usage on a ‘pay as you save’ basis so the future operations of the scheme will stay with the meter rather than the tenant. There will be the ‘Golden Rule’ which states that measures installed through the scheme must deliver savings which exceed the repayments. See more at DECCthe government Department of Energy and Climate Change and at the UK Green Building Council
Nottingham Energy Partnership are a not for profit organisation who “devise, manage and deliver domestic and commercial projects that tackle fuel poverty, cut carbon emissions, and make businesses more sustainable”