UK solar installed costs, by year, region, sector and size
The official statistics series in one file: 336 rows covering thirteen years of history, three years of monthly and regional detail, and the split between new build and retrofit. Free to download and free to reuse.
Thirteen years of official UK solar cost data, restructured into one file.
336 rows: annual and monthly figures, eleven regions, domestic against non-domestic, new build against retrofit, and three system size bands — each with a mean, a median where the source publishes one, and an installation count.
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UK solar PV installed cost per kW
336 rows — breakdown, basis, year, dimension, size band, mean, median and installation count.
Download the CSV · 20 kB · Open Government Licence v3.0
Credit as: Contains public sector information licensed under the Open Government Licence v3.0. Compiled by solar.org.uk from DESNZ, Solar photovoltaic (PV) cost data.
The provenance, the basis warning and the “do not sum across breakdowns” caveat travel inside the file as header comments.
What it shows
- 0–4 kW
- 4–10 kW
- 10–50 kW
Declared net capacity basis. The source publishes its long back-catalogue on DNC and its current-year tables on total installed capacity. The two are different denominators, so the figures here are not comparable with the other cost charts on this site — read the shape of the line, not its level against them.
The line most people expect to see is a steady fall. It is not what the data does. In cash terms a domestic installation costs about 6% less per kW than it did in 2013/14 — and between those endpoints it fell to a trough in 2019/20 and then rose 53% above it by 2023/24.
Total installed capacity basis, so not comparable with the long history chart, which the source publishes on declared net capacity.
Total installed capacity basis, so not comparable with the long history chart, which the source publishes on declared net capacity.
Region is a weak effect. The gap from the dearest region to the cheapest is a few hundred pounds per kW, and it is smaller than the gap you will find between three quotes on your own roof. Cost per kW has the full table.
Total installed capacity basis. Total includes non-domestic installations; Domestic is domestic only.
Columns
| Column | What it is |
|---|---|
breakdown | Which of the source’s tables the row comes from: annual, monthly, regional, sector, newbuild or history |
basis | TIC (total installed capacity) or DNC (declared net capacity). Never compare across these |
year | Financial year, e.g. 2025/26 |
dimension | UK, or the region, month, sector or new build category for that breakdown |
band | System size band, or all bands where the source publishes an all-sizes figure |
mean_gbp_per_kw | Mean installed cost per kW |
median_gbp_per_kw | Median, where the source publishes one for that cut |
installations | Number of installations behind the figure |
The basis trap
This is the one thing that will bite anyone who plots this file without reading it.
The department publishes its long back-catalogue on the declared net capacity basis and its recent detailed tables on total installed capacity. Those are different denominators. Put the history series and the current-year series on one axis and you will see a fall that is an artefact of the arithmetic rather than anything that happened in the market.
That is why every row carries a basis column, why the header comment says so twice, and
why our own charts label it on their face.
How it was made
Two scripts, and neither writes a partial file:
scripts/data/fetch-solar-costs.py— fetches the published workbooks.scripts/data/build-solar-costs.py— reads them intodata/solar-costs.yaml. Every value is range-checked against a plausible floor and ceiling before it is written, and the script exits rather than emit a file with one bad number in it. The workbooks put their headers on row 4 or row 5 depending on the sheet, so the header row is detected rather than assumed.scripts/data/build-downloads.py— emits the CSV published here.
If you disagree with a figure, run them and see whether you get the same one.
Sources
- Solar photovoltaic (PV) cost data Release 2025-26, published 28 May 2026. Derived by the department from the MCS Installation Database.
Contains public sector information licensed under the Open Government Licence v3.0.
Sorry to hear that. What was the problem?