3. Micro power doubts

The Energy Saving Trust says that micropower could provide 30-40% of the UK’s electricity needs by 2050. However many local authorities insist householders apply for planning consent for micro-wind system- something Yvette Cooper, the planning minister, felt had to change: ‘It is patently absurd that you should be able to put a satellite dish on your house but have to wrestle with the planning process for small-scale micro-generation, which is no more obtrusive and can have a real impact on tackling climate change,’ she told The Observer (25/6/6). ‘We want much more micro-generation to be treated as permitted development. We are reviewing the impact of a wide range of technologies so we can take account of things such as the impact on neighbours or listed buildings before consulting on details later this year.’ The Town and Country Planning Association welcomed government plans: ‘We’re moving into an era of localised renewable energy. Current planning regulations were designed for a different era’. But the Obersever said that concerns persist that the urban landscape will be disfigured by a surge of wind turbines and solar panels. A spokesman for English Heritage said: ‘We recognise the importance of finding new sustainable sources of energy but we also recognise that some renewable energy technologies have the potential to cause serious damage.’ The Conservative leader, David Cameron, got agreement on the installation of a 1.1 meter Stealthgen wind turbine from Kensington and Chelsea Borough Council, but evidently ran into trouble with some of his neighbours, one of whom said it would be an ‘eyesore’.

The Sunday Times (25/6/06) meanwhile ran a warning that there there was ‘no guarantee that putting a turbine on your roof will produce enough electricity to make worthwhile savings’. It noted that B&Q was planning to sell the Windsave rooftop wind turbines at its ‘Warehouse’ stores for about £1,600, including installation. Windsave, which is also to offer its turbines via the internet, said its 1.75 metre turbine produces 1,000-2,000 kWh a year. Renewable Devices claims that its Swift 2 metre turbine produces 2,000-3,000 kWh p.a., and could save the householder up to £300 a year, including the value of green energy generation certificates.

However, even, with 30% of the cost being offset by a government grant under the new Low Carbon Building Programme, the Times warned that consumers might find not find the economics as attractive as was suggested. It reported that one consultant who sits on the government’s renewables advisory board and has undertaken extensive testing of some of the turbines says: ‘We found the performance of them is on average between 10 and 25 % of what the manufacturers are claiming.’

The Energy Saving Trust told the Times that low wind speeds in urban areas mean that most installations will never come near the claimed performance. ‘In better locations we’d expect wind speeds of six metres per second, but in urban areas, with lots of other buildings around, you’re probably looking at four (metres per second), and that will affect performance considerably.’

Nick Martin of the Hockerton Housing Project (HHP), in Nottinghamshire, says that Swift and Windsave’s performance claims ‘defy the law of physics’ and that they will produce much nearer to 10% of the average household’s energy needs. The Times added ‘It is an awkward situation for the EST, which administers a new Department of Trade and Industry programme to fund 30% of the cost of small-scale renewables. The Swift and Windsave turbines were accredited under a previous government scheme, Clear Skies, which did not require them to meet performance criteria, Archibald says. Clear Skies rolled over into a new scheme, the Low Carbon Building Programme, in April, meaning that the two turbines still qualify for grants- although the government has not yet announced the criteria that products will need to meet.’ But it noted that Scottish and Southern Energy, which has a stake in Renewable Devices and is looking to offer the Swift turbine to another 400-500 customers this year, stood by the 2,000-3000 kWh performance claim, which it said was based on wind speeds of between 4.4 and five metres a second, although it agreed that ‘output does vary’ and that obstructions, such as nearby trees or buildings, will eat into performance.

David Gordon, chief executive of Windsave, told the Times that even at four metres a second, the turbine will produce more than 500 kwH a year, taking £60 off the average bill. Consumers will also be eligible to get a green energy certificate worth £60 from the government, taking the annual value of the electricity up to £120, ‘and that has to be worth having’. He added that they will be sold to order, and the company’s installers will put them up only if windspeeds are at least 3.5 metres a second. This will be judged using data from the DTI, which has windspeeds for every postcode in Britain. However Niki Martin from HHP claimed that the DTI’s windspeed data was misleading: ‘The DTI computer generator looks at topography but doesn’t take into account fences, trees and buildings, which affect windspeeds’.

Martin was also worried about structural damage to houses if they are not installed properly: ‘If you bolt it to the end of the gable of a Victorian house made with lime mortar, it’s going to come apart’. There could also be vibration problems with some turbines. The Times noted that Windsave’s sales literature warned that its wind turbines were not suitable for some roof types, including lime mortar, and says every building will be tested by its installers for suitability. Similarly for the Swift turbine- Scottish and Southern will require a full structural survey by its engineers before a rooftop device is installed.

Micro power support

Responding to a Parliamentary Question on 26th June, Energy Minister Malcolm Wicks noted that as well as there being grants for installing micropower technologies available to householders under the new Low Carbon Buildings programme, ‘Microgenerators producing electricity can also benefit from the Renewables Obligation (RO) where they will receive one Renewables Obligation Certificate (ROC) for every 1MWh of eligible renewable electricity generated. We will also be consulting later this year on changes to the RO, which will allow microgenerators to gain further benefits. This includes allowing agents to act on behalf of microgenerators; amalgamating generation from several microgenerators; and removing the need for a sale and buy-back agreement.’

Mark Lazarowicz’s Climate Change and Sustainable Energy private members Bill, which the government supported, is now law and should make it easier for excess energy from domestic miropower units to be sold back to the utilities by encouraging energy companies to establish schemes that reward smaller scale generators for their exported power. Other measures in the Act will make it easier for small generators to receive the financial benefits of renewable obligation certificates- typically around £20-30/MWh. The Act also calls for more promotion of local level heat & power and a further provision added by the Government will help to open up the development of renewable projects on the Scottish islands by extending to 2024 a cap on electricity transmission charges. The Energy Review backs micro power, but says a ‘heat obligation’ would be difficult.

Green Tariffs

Wicks has also noted that, ‘Ofgem will shortly be publishing a response to its consultation on the Revision of Guidelines on Green Supply Offerings and we will consider the introduction of an accreditation scheme for green electricity tariffs in the light of this’. Readers may remember that, some while ago, a voluntary ‘Future Energy’ accreditation scheme was initiated by EST, but this was not widely taken up. The Ofgem report will include detailed guidelines on the criteria to be used for green tariffs.

The item (3) above is from Renew 163, Sept Oct 2006, but was inadvertently omitted from Renew On-Line 63 ii