Question to the Department for Business, Energy and Industrial Strategy:

To ask the Secretary of State for Business, Energy and Industrial Strategy, what comparative estimate his Department has made of the typical cost of (a) retrofitting eight solar panels to a home and (b) installing eight solar panels at the time of building a new home.

The cost of installing a domestic solar PV system varies with the type of solar panels, space for installation and roof design. In December 2021, the Department for Levelling Up Housing and Communities published indicative data on costs for fitting solar panel systems on new homes. The fixed cost to install a solar PV system of under 4kW capacity system is £1,100, with a variable cost of £600 for each kW installed[1]. Data published by the Department for Business, Energy and Industrial Strategy in May 2021 indicate the mean cost per kW for installations smaller than 4kW, whether new build or retrofit, has reduced from £2,080 in 2013/14 to £ 1,628 per kW installed in 2020/21[2].

Research by consumers’ association Which?[3] and the Energy Savings Trust estimates that the cost of a typical domestic solar installation of 3.5kW capacity and comprising 10 to 15 panels, is around £4,800 [4].

[1]https://assets.publishing.service.gov.uk/government/uploads/system/uploads/attachment_data/file/1040631/Domestic_Part_L.pdf

[2] https://www.gov.uk/government/statistics/solar-pv-cost-data

[3] https://www.which.co.uk/reviews/solar-panels/article/solar-panels/solar-panel-costs-aDxBY2v7kr60

[4] https://energysavingtrust.org.uk/advice/solar-panels/#jumpto-17 and https://energysavingtrust.org.uk/advice/solar-panels/