Domestic energy efficiency

A four-year, multi-partner project aims to provide householders with a one-stop shop for technology tailor-made to lower the energy needed to provide heating and hot water.


The rate of building renewal runs at about 10 per cent a year, so even if all new-build housing is zero carbon by 2050, existing stock needs to be made more energy efficient through retrofit or refurbishment to achieve government targets.


The CALEBRE (Consumer-Appealing Low Energy Technologies for Building Retrofitting) project aims to address this by reducing energy demand, decarbonising the supply to buildings and developing policy to promote that process.


Prof Dennis Loveday, of the sustainability research school at LoughboroughUniversity, said: ‘The core issue is the householders themselves, what kind of interventions they are prepared to accept and how they interact with them.’


The EPSRC and E.ON UK provided £2m in funding to promote energy research in this area and brought together research groups from six universities — Warwick, Ulster, Nottingham, Oxford, Herriot-Watt and Loughborough.


The academic partners will be guided by a steering group of industrial stakeholders, including the Commission for Architecture and the Built Environment (CABE), the Building Research Establishment (BRE), the Chartered Institute of Building Services Engineers (CIBSE), Inbuilt Consulting, Baxi Group and Care & Repair — a government advisory committee on housing and older people.


‘We aim to produce a software tool for householders or stakeholders to discover the best technology solution to achieve energy efficiency for their particular type of building,’ said Loveday.


He said this solution would prevent the problem of ‘transaction exhaustion’ that could occur with all the separate investigation, purchasing and installation home owners would otherwise need to do, and which may not offer the best results.


The group plans to investigate the energy savings from a range of promising technologies — initially through reducing the energy demand of the home.


‘One of the most effective ways of doing this is through insulation,’ said Loveday. ‘If you look at the typical UK home, the biggest energy demands we will have is space heating and water heating.’


Experts from Ulster and Warwick are looking at the potential to reduce heat loss through advanced insulation, for example in the form of vacuum panels and vacuum glazing.


Oxford and Nottingham researchers will also study techniques using nanocomposite materials such as Aerogel, which combines insulation with heat storage within the surface to make houses more comfortable.


To reduce carbon emissions from the supply side, an Ulster team will investigate efficient electric heat pumps and Warwick will look at gas-fired ones, with the aim of integrating them into existing buildings.


Alongside reducing demand for energy and decarbonising the supply, the third element of CALEBRE will be managing and controlling the heating of the building, such as through ventilation heat recovery. This is being investigated at Herriot-Watt, which will also develop the software tool.


A key element to the project is to introduce technologies that will appeal to the consumer with minimal inconvenience, and Loughborough researchers will focus on user-centred aspects, informed by a panel of 200 householders. These modified technologies will be tested first in the laboratory, then trialled in an occupied 1930s-style test house built on the Nottingham campus.


The test house is heavily instrumented to take measurements of temperature, air speed and environmental variables, and to track the occupants to measure the energy implications of their activities.


The research will also use a heated, breathing thermal mannequin to measure the heat emission as it would occur from a human and provide information about the sensation of thermal comfort.


After adjustments are made to the technologies, Nottingham will also look at the manufacturing aspects, ensuring their economic viability.


By the end of the project in 2012, the team expects to have a validated package of measures and technologies available for installation, and to be able to inform the government about designing policies with financial incentives.


A separate EPSRC project led by Dr David Shipworth at ReadingUniversity is investigating systems to monitor and control home heating energy usage while keeping a comfortable environment for the occupants.


Berenice Baker