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How much will you save?
The Energy Saving Trust (EST) calculates that the typical home will save £300 a year, although this depends on how much energy you use and how much sunlight you get.
It will take between 11 and 27 years to recoup the cost of your panels, according to the EST, so you need to be in it for the long term. Work out your potential benefits on the EST calculator at energysavingtrust.org.uk.
What can you earn from the Smart Export Guarantee scheme?
Suppliers can set their own prices for buying your excess power. A Times investigation in April found that some suppliers were paying as little as 1.5p per kilowatt hour (kWh), compared with the 28p they can charge under Ofgem’s price cap.
The Eco Experts, a group of climate-savvy writers who help people to cut their energy bills and reduce their carbon footprint, said that 16 suppliers were participating in the scheme on July 6. EDF is still bottom of the pile in paying 1.5p while British Gas pays 3.2p, Ovo 4p and Scottish Power 5.5p. Octopus Energy offers the best rate of 7.5p.