Dr Sung is leading a project (Integration and Optimisation of Building-integrated Renewable Energy Systems in UK Homes) which aims to assess the viability of the technologies currently available to house builders/owners who are looking to meet the challenge of climate change and carbon footprint reduction as a wider target and the Governments agenda/targets as a sharper focus. Tony and his team have been working with one of the nation's leading house builders to attempt to quantify the value of renewable technologies in terms of return on cost, energy efficiency and contribution to reduced carbon demand.

The nation's leading house builder, Barratt's, have recently concluded an experimental 'eco-village' in west Lancashire. This involved installing technologies in a cul-de-sac of 7 new family homes and monitoring them over a 15 month period. The homes were un-occupied for the period of the study. The team from the University of Manchester have been responsible for data-collection and analysis.
The various technologies have now been removed from the houses and taken back to the university, and following the initial report, due shortly, they will maintain a number of these technologies over the coming months/years to provide further data.

The technologies involved in the Barratt's 'eco-village' experiment, together with Tony's observations, briefly as follows:

Rainwater Collector: Works well... Supplemented from mains - but as yet, there is no way of measuring the amount of 'mains' top-up. Manufacturers do not supply the technology required to measure this.

• Solar Thermal Collectors [Photovoltaic, Flat Plate and Evacuated Tube]: 2.5m Square of collector - has proved able to provide a standard tank full of hot water each day on average - but of course this is not 'on demand' and when its gone it's gone. According to the results gathered the output is negligible on about 150 days per year, and overheating may become a problem on about 20 days per year
• Ground Source Heat Pump [GSHP]: Three systems have been tested and although performing at only a coefficient of 2.6 - which appears quite low, in mitigation they were set to produce an output of 55°C. If set to a more realistic 35°C then they would reduce CO² emissions by around 62% and has a payback period of around 15 years using today's electricity prices.
  
• Micro-Combined Heat and Power [Micro CHP]: Two types were tested. On average the efficiency of the sytems is 80% and worked very well with a heat store. However the initial enthusiasm for these units has been tempered by the fact that the manufacturer has withdrawn them from the market for further development.
  
• Wind turbines: Performance was seen to be poor, with some of the turbines used in the experiment actually consuming more energy than they produced! (The electronics which govern them using more electricity than the turbine output)
  
• Solar Panels: In the way they have been used thus far - we are not making the best use of the energy produced. For example the summer generates the highest output of usable energy at a time when the house itself is consuming at it's least. If we were to apply some reverse thinking and introduce much more highly insulated homes then the energy produced in the winter months though much lower might be sufficient to keep the house warm, whereas in the summer the emphasis could shift to cooling it.
  

In conclusion the report will suggest that there is still a very long way to go in the evolution of these technologies, currently houses fitted with these technologies from new cannot attract an NHBC Certificate because the manufacturers of the technologies are not prepared to support them as yet with suitable guarantees, nor is the market able to support householders (How many local plumbers/heating engineers are there who could be called out to maintain/repair your Micro CHP?a and so there are training and tooling up issues as well as technological ones). The report will also emphasise that metering and control of the renewable technologies should have an IT Interface to allow the householder to monitor performance through their PC. Currently, there are IT Tools available that can estimate the payback of technologies - but they don't integrate. There is real scope/need in the market for someone to develop and integrate suitable tools.

Further details on the key findings of the project please see: http://www.barratt-investor-relations.co.uk/media/releases/Content.aspx?id=1318

In response to a question from the floor Tony estimated that at current prices it would take an investment of approximately £5000 to get a house to Level 4 of the Government's recent 'Code for Sustainable Homes' and £15000 to achieve a level 5 rating. Purely on economic grounds , and at these levels, without the back up of legislation, how many householders can be persuaded to retro-fit these technologies with at minimum 15 years before they see a return on their investment? ... more>