When estimating solar costs there will obviously be big variations depending on the size of system, complexity of installation and cost of the products installed. As a rough guide a 1kW system will cost about £7,000, a 2kW system about £10,000 and a 3kW system about £13,000. If your building needs complicated scaffolding to enable access that could cost an addition £500. In-roof arrays and photovoltaic tiles (to replace your esoxisting roof tiles) are much more expensive than on-roof arrays. During a site visit by an installation company electrical work and/or building work may be required before a photovoltaic array can be installed. If the costs for these seem high then consult your local Building Control department for advice first.
The introduction of the Feed in Tariff system on 1st April 2010 means that for every kilowatt hour (kWh) of electricity generated a fee is payable by your energy company. For systems less than 4kWp this is £0.433 per kWh. Therefore:
• A 2.8kWp system produces 2,100 kWh’s per year.
• You will get £909.30 per year as a FiT payment (although this will increase year on year as FiT payments are Retail Price Index (RPI) linked.
• You will also get 3p per kWh for 50% of the generated electricity as it assumes 50% is exported, an additional £31.50
• Plus you should make a saving on your electricity bill, assuming you use 50% of the electricity generated. Therefore based on the average price a domestic customer pays of £0.125 per kWh you could save a further £131.25 per year
• In total £1,072.05 each year for 25 years
