Solar PV (photovoltaic) is a great technology because it is so flexible and easy to manage. In most cases, once you have fitted it and connected to the grid you can forget about it, and watch your carbon emissions and energy costs fall and stay down for the next 25 years or so.
One of the many projects we completed last year was to help a local authority plan and install an 11kW solar photovoltaic system on a sheltered housing scheme. This is one of my favourite projects because it brought modern low carbon technologies to a group of older people who probably wouldn’t otherwise have thought about renewables. Each of ten 1970s bungalows was (retro)fitted with its own system, and it was fantastic to have the residents phoning up regularly to ask when they would start to see the cash rolling in!
In practice, in the UK on unshaded sites you should expect a 1kW solar PV system to cover about 8-10 square metres of roof space, cost around £6000 before grants (which can be quite generous) and to generate around 800-1000 kWh of electricity a year – bringing in about £140 at current electricity prices.
Solar PV raw material prices are currently falling rapidly due to global economic conditions, and while this is almost certainly temporary, we should look be looking forward to continued reductions in system prices over the next 10-20 years as the scale of the worldwide industry grows.
PV is already hundreds of times more common in many other countries of the world than it is in the UK – and this is nothing to do with climate. Our government is yet to get its act together in structuring the energy industry fairly – particularly to make sure electricity prices properly reflect the value of carbon emissions. When they do this (and there are some signs they are heading in the right direction) this could open the floodgates to a larger scale UK PV industry.
Photo by James Cridland