The cost of solar panels in the UK varies depending on the size and type of system, with systems ranging from as little as £1000 for a small domestic system to over £100,000 for large commercial systems. Most solar panel systems in the UK are eligible for the Feed-in Tariff, a government subsidy which pays a fixed rate for any electricity exported to the grid. Solar panel systems are a great way to reduce energy bills and reduce your carbon footprint. Installation Cost of Solar Panels