- The Observer,
- Sunday September 22 2002
It is widely touted as the energy source of the future. It's clean, does not produce greenhouse gases, and there is an endless supply of the raw material - light.
Photovoltaic technology exploits the property of semi-conductor materials such as silicon to emit electricity when exposed to daylight. The technology has been around for some time, but use of PV panels in the UK is set to grow with the first grant support scheme for householders. The government will pay up to half the cost for homeowners, and up to 65% for some public buildings.
One of the scheme's first beneficiaries is Trevor Nicholson, a 34-year-old lawyer. His house is one of a row of Victorian artisans' dwellings in Bethnal Green, east London. He opted for PV panels after considering the other main source of solar energy: black-painted panels which heat water pipes. Both generate electricity or hot water during the day when he will usually be out.
But while surplus electricity can be sold to the national grid, subsidising the electricity he will have to buy in the evening and night from the grid, the hot water system would provide water for his house alone when he wouldn't need it.
"That's fine for households with children who need lots of baths," he says. But the only other member of Trevor's household is his dog, Oria.
Another consideration is that PV panels are powered by light rather than heat, so they continue to generate electricity, albeit in smaller amounts, on dull days.
Planning permission is required for PV panels, but this is relatively easy to obtain as many installations, including Trevor's, are not visible from the street. He lives in a conservation area, but had no problems. The scheme is administered by the Energy Saving Trust, and the application procedure includes assessment of the viability of individual proposals. Trevor has a south-facing roof, which is obviously advantageous.
Because his roof is in two sections, he purchased a pair of panels. The cost and their installation and most of the additional equipment was £13,366, of which half has been met by the grant. Because the panels are heavy, extra joists had to be inserted. They generate DC power at 1,000 watts, which is converted to domestic AC. Further requirements were two new electricity meters (£180 each), to measure the electricity flowing to and from the national grid.
Trevor's average consumption is around 3,000 kilowatts a year and the panels are likely to generate 1,600. In addition, the price he gets for the electricity he sells back to the grid will be fractionally more - about 1p per kilowatt - than he pays for his remaining supply. At first sight then, he should save slightly more than half his annual electricity bill.
However, it will still take 50 years of electricity generation to cover the cost of the system. So does PV technology enhance the value of a property? Where it's a feature of new houses, vendors are adding its cost into purchase prices. However, this is not feasible for existing buildings; unless a purchaser is specifically looking for a home with a PV installation, the panels are unlikely to add value.
Trevor is well aware of these considerations, but says. "I didn't do it for financial reasons. Everyone has to do their bit to help the environment."
More information
Energy Saving Trust Grant inquiry line: 0800 298 3978
Solar Century 020 7803 0100 (email: enquires@solarcentury.co.uk)
