Thermal or Photovoltaic (PV) solar panels

Of the two different types of solar panel on the market, thermal (for hot water) and photovoltaic or PV (for electricity) how can a householder choose which is best?

Currently a feed-in tariff (FIT) exists in the UK for PV panels where the government will pay up to 43.3p per kWh of electricity produced, depending on the type of house and panel. This enables schemes such as the one offered by Sunhive to be set up where householders can have PV panels fitted for free which is paid for by the return from the FIT. A similar FIT scheme for thermal panels is due to be set up from April 2011 with the government paying 18.3p per kWh of energy produced.

An average 2kWp PV system  can cost around £8,000 and needs 16m2 of space. This produces around 1800kWh of electricity per year in Sussex, making £745 from the FIT. Assuming that 50% this is used, a further £27 can be made from selling the excess back to the grid at 3p per kWh with a saving of around £117 in bill reductions. This then makes the financial gain of PV panels roughly £890 per year. The amount of carbon saved yearly equates to around 1.35 tons.

Thermal panels can cost around £4,800 for a 3.4m2 panel and will produce about 1750kWh per year, making an initial payout of £320 and with a further £68 reduction on heating bills. The financial gain from using thermal panels will then be around £388 per year. The amount of carbon saved amounts to roughly 1.1 tons.

The figures given here are calculated based on averages and actual results will differ according to a household’s particular heat and electricity requirements as well as the type and location of their panels. For more detailed information please consult the list of sources below.