Business Rates and a Solar Carport

England: the exception runs to 31 March 2035

The plant and machinery regulations were amended by S.I. 2022/405 to create “excepted renewables plant and machinery” — defined by energy source, including photovoltaics, and covering generation, storage, transformation and transmission — together with “excepted EVCP plant and machinery”. Both are excluded from the rateable value for any day from 1 April 2022 until before 1 April 2035. No extension beyond 31 March 2035 exists anywhere in England, Wales or Scotland, so a 25-year investment case should not assume one.

What is still valued

The exception is narrower than it sounds. The valuation guidance is explicit that the land and settings accommodating the plant remain rateable. Below roughly 50 kW the residual value is likely to be de minimis; above 50 kW the supports, brackets and settings are valued, and instructions for large retail sites treat panel supports, framework, fixings and brackets as rateable items. Export-led generation above about 10 kW is normally treated as a separate hereditament in its own right.

One thing we will not tell you either way: whether a car-park canopy's steel is rateable, or changes the car park's rateable value. No primary source addresses it — not the valuation manual, not the property-class sections, not the Scottish assessors' notes. Anyone stating it confidently is guessing. Put the question to the valuation office for your site, noting that the Valuation Office Agency became part of HMRC in April 2026.

Wales and Scotland

Wales: WSI 2023/1229 applies the same exception from 1 April 2024 to 31 March 2035, and improvement relief runs from 1 April 2024 under WSI 2023/1354. A relief for EV charging bays and forecourts was announced on 11 August 2026, running to 31 March 2036 — discretionary for 2026-27 and statutory from 2027-28, backdatable to 1 April 2024. A car park with some chargers assessed as one hereditament is not eligible.

Scotland: SSI 2023/32 applies the exception from 1 April 2023 to 31 March 2035.

England's EV charging relief is narrower than it reads

The 2025 Autumn Budget confirmed 100% relief for EV charging for ten years to 31 March 2036, backdated to 1 April 2023. It reaches only separately assessed charging hereditaments — those with their own rateable value under the charging property class — and is delivered as discretionary relief reimbursed by government. Chargepoints installed in bays inside a larger hereditament, with no rateable value of their own, do not qualify. Host-operated chargers are currently neither separately assessed nor treated as adding value.

Improvement relief, and when it helps

England's improvement relief, from 1 April 2024, gives twelve months' relief from the higher bill where qualifying works — including the addition of rateable plant — increase the rateable value. If the settings and supports of a large canopy do move your assessment, this is the relief to ask about, and it is time-limited, so the conversation belongs at commissioning rather than at the next revaluation.

What to do, in order

Ask three questions before commissioning. Is the generation plant clearly identified as excepted renewables plant, so it is outside the rateable value until 2035? Are the supports and settings being valued, given the scheme is above 50 kW? And will any charging be separately assessed, which is what decides whether the EV relief is available at all? Those answers, plus the capital allowances on a solar carport, are what make the whole-life number in a solar carport cost model defensible.