How much do solar carports cost?

The honest headline on solar carports is that they cost more per kilowatt than rooftop solar, and it pays to understand why before you read a quote. A car park canopy is a steel structure first and a solar array second. The columns, beams, purlins, and the canopy frame account for roughly 45 per cent of the total project cost. A rooftop install reuses a roof that already exists, so it skips that structural spend. That is the whole reason solar carports run around £1,200 to £3,000 per kWp installed (ex-VAT) against £600 to £1,000 per kWp for rooftop.

The figure that matters most for your budget is not the per-kWp rate, it is the bay count. Because the steel cost is largely fixed, a bigger car park spreads it across far more generating capacity and brings the per-kWp cost right down. A 10-bay scheme never gets economical. A 50-bay scheme starts to work. A 200-bay scheme gets materially better value again. As a rough guide, a 100-bay car park carries roughly 150 to 200 kWp and runs around £180,000 to £350,000, while a 200-bay scheme of roughly 300 kWp runs around £290,000 to £345,000. The bigger the car park, the lower the cost per unit of power.

How a carport is sized, and what it generates

Solar carports size from the parking footprint, not from a building roof. Plan around 12 square metres of canopy per standard bay, carrying about 1.5 to 2.0 kWp (four to six panels) per bay. At UK yields of roughly 850 to 1,000 kWh per kWp a year, that works out to around 1,200 to 1,300 kWh generated per bay annually. A 100-bay car park therefore generates roughly 120,000 to 130,000 kWh a year, enough to make a real dent in site electricity costs and feed EV charging. Single-row, double-row, and tandem canopy designs let us fit the array to almost any layout, including disabled and EV-priority bays.

What the carport returns, beyond bill savings

Comparing a carport's payback to rooftop on panel savings alone misses the point. A carport returns value a roof never can. First, the EV charging: the canopy carries the chargepoints your staff, customers, or fleet need anyway, fed behind the meter at your generation cost rather than full grid retail. Second, the Workplace Charging Scheme grant on the sockets, up to 75 per cent of install cost, capped at £500 per socket for up to 40 sockets, to 31 March 2027. Third, the tax relief: the PV plant qualifies for 100 per cent Annual Investment Allowance, worth up to 25 per cent effective relief in year one for limited companies under the capital allowances rules. Fourth, the visible brand asset. We model the full blended return, solar savings plus charging income plus grant plus tax relief, not just the panel-only payback. Typical carport payback is 8 to 10 years on its own, and the blended figure is considerably stronger.

Export income and self-consumption

The best economics come from self-consuming generation at full retail rate rather than exporting it cheaply. A carport connects behind your meter, so it offsets on-site building load first, then powers EV charging, and only the surplus exports. Sites with strong daytime load, retail trading hours, hospitals, weekday offices, self-consume most of what they generate. Sites that sit empty out of hours, weekday-only offices, weekend-only attractions, export more, which is where the Smart Export Guarantee matters most. SEG tariffs sit around 4 to 15p/kWh as of 2026, supplier-set, so it pays to shop around for the export rate.

Financing routes

Most clients fund a carport one of three ways. Capital purchase plus AIA is the simplest: you own the asset, claim the full first-year tax relief, and keep every pound of saving. Asset finance spreads the cost over five to ten years and is often cash-flow positive from month one for daytime-occupied sites, because the energy saving exceeds the repayment. A power purchase agreement (PPA) involves a third party funding and owning the system while you buy the power at an agreed rate below grid, useful where capital is constrained, though it returns less over the life of the asset. For multi-let and leased car parks, service-charge recovery and landlord-funded models are well established, and we provide the heads-of-terms framework.

The costs people forget

A few items sit outside the headline canopy price and belong in any honest budget. The G99 grid connection is the big one: where total inverter capacity exceeds 17 kW per phase a DNO application is required, and on capacity-constrained networks the connection can take 6 to 18 months, which is why we submit early. A ground and structural survey is needed because carport foundations are designed to the site's ground conditions. Drainage adds cost: a new impermeable canopy over a previously permeable car park triggers a SuDS requirement under Class OA, so gutters, downpipes, and a soakaway or permeable discharge zone go into the design. And ongoing operation and maintenance runs around £8 to £12 per kW per year for systems above 250 kW, covering electrical inspection, inverter checks, and structural inspection of the steel and gutters.

Set against all this is the number that makes the case: the grid price you avoid. Commercial electricity remains expensive, and every unit a carport generates and you self-consume displaces a unit you would otherwise buy at full retail. For more on the funding side, see our grants and funding guide, and when you are ready we will model the full blended return for your site, request a quote and we will turn it around within 7 working days.