Solar Canopy: Buy Outright vs PPA (Power Purchase Agreement)

There are two fundamentally different ways to put a solar canopy over your car park. You can buy it outright — pay the capital, own the asset, and keep every pound of saving it generates. Or you can sign a Power Purchase Agreement (PPA) — a funder pays for and owns the canopy, and you simply buy the electricity it produces at a fixed rate below the grid price, with nothing to pay upfront.

Neither is “better” in the abstract. They suit different balance sheets, different appetites for risk and control, and different tax positions. This guide lays out the real numbers for the UK in 2026, puts the two routes side by side, and gives you a clear decision framework so you can tell which one fits your organisation.

The two models in one paragraph each

Buy outright (capital purchase). You fund the canopy from cash or a loan. At commercial scale a canopy runs £900-£1,400/kWp, or £1,200-£3,000/kWp on smaller, complex sites — roughly £6,000-£12,000 per parking bay. You own the structure and the panels, so you keep all the electricity it generates. Self-generated solar costs about 10p/kWh over its lifetime against grid electricity at 25-47p/kWh, so every self-consumed unit is worth roughly 2x an exported one. You also claim the tax reliefs. Solar-only payback is 8-12 years (7-11 with EV charging), after which the generation is close to free for the rest of a 25-year-plus asset life. See our full cost breakdown for what drives the number.

PPA (Power Purchase Agreement). A third-party funder designs, pays for, installs and owns the canopy on your site. You pay nothing upfront. In return you agree to buy the power it produces at a fixed rate below your grid tariff, typically over 10-25 years. The asset sits on the funder’s books, not yours — it is off balance sheet. You get cheaper electricity and covered parking from day one, but the funder keeps the bulk of the financial return and owns the equipment until (if the contract allows) you buy it out at the end.

Head to head: the numbers that matter

Factor	Buy outright (capex)	PPA (zero-capital)
Upfront cost	Full capital: £900-£1,400/kWp at scale (£6,000-£12,000 per bay)	£0
Who owns the canopy	You	The funder, for the term (10-25 yrs)
Balance sheet	On your books as an asset	Off balance sheet
Electricity cost to you	~10p/kWh lifetime (you generate it)	Fixed PPA rate, below grid — but above ~10p
Who keeps the saving	You keep 100%	Funder keeps most; you get the discount vs grid
Tax reliefs	You claim £1m AIA + 50% FYA	Funder claims them (they own it)
Maintenance / insurance	Your responsibility	Usually the funder’s
Break-even / payback	8-12 years, then near-free power	No “payback” — you save from day one but never own the full return
Control	Total: expand, re-wire, re-tender freely	Constrained by the contract for the term
End of term	You own a 25-yr+ asset outright	Buy-out, extend, or funder removes kit
Best for	Cash-rich, tax-paying, long-hold owners	Capital-constrained bodies wanting zero-outlay solar

The tax angle — the biggest hidden difference

If you buy outright and you are a UK business, the tax system does a lot of the heavy lifting. A commercial solar canopy is plant and machinery, so you can deduct 100% of qualifying spend up to £1 million in the year of purchase under the Annual Investment Allowance (AIA) — and for most single-site canopies the whole cost sits comfortably inside that cap. Where spend exceeds the AIA, the 50% First-Year Allowance applies.

One warning we repeat because the market gets it wrong: solar is special-rate plant and is EXCLUDED from full expensing. Anyone telling you a solar canopy qualifies for “full expensing” is mistaken — the relevant first-year relief is the 50% FYA, and for most projects the £1m AIA already gives you a 100% first-year deduction anyway. On top of that, England offers a business-rates exemption on renewable generation to 31 March 2035, and you can claim the Smart Export Guarantee (roughly 1-15p/kWh) on anything you export, provided the system is MCS-certified.

Under a PPA you claim none of this. The funder owns the asset, so the funder takes the AIA, the FYA and the SEG income. That is precisely how the model works — the funder recovers its outlay through the tax reliefs and the margin on the power it sells you. It is not a flaw, but it does mean the total lifetime value of a bought canopy is materially higher for a tax-paying business. Our grants and funding page has the full, current picture of every relief, plus what has closed (PSDS, the staff-fleet EV grant) so you do not build a plan around a scheme that no longer exists.

Break-even: two different clocks

The two routes do not share a definition of “success”, so compare them carefully.

Buying has a genuine payback: the point where cumulative savings repay the capital. For a canopy that is 8-12 years solar-only, or 7-11 with EV charging — never the five-year figure some sellers quote, which ignores the structural steel. After break-even, you are generating at ~10p against 25-47p grid for another decade-plus, and that back half of the asset life is where a bought canopy makes its real money.

A PPA has no payback because you never pay the capital. Instead you save a margin from day one — the gap between your grid tariff and the PPA rate. That is attractive if you have no capital to deploy, but the cumulative saving over 25 years is smaller than owning, because the funder is taking the difference between your ~10p generation cost and the rate they charge you. Put simply: buying wins on total lifetime value; a PPA wins on cash flow and zero risk.

Control and flexibility

Ownership brings freedom. Buy the canopy and you can add EV chargers, bolt on battery storage, re-tender your maintenance, expand the array, or refinance — all on your own timetable. The canopy powers 7kW and 22kW AC charging and site lighting directly (it will not run standalone 50kW+ DC rapids — those need grid and battery), and self-consumed solar is worth roughly twice exported, so many owners tune the system hard for self-use over the years.

A PPA trades some of that freedom for the zero-capital deal. You are committed to the contract for its term, the funder controls the asset, and changes — adding chargers, altering the layout, ending early — are governed by the agreement. Read the exit terms, the rate-escalation clause and the end-of-term buy-out before you sign. A canopy is a 25-year-plus structure engineered to Eurocode 1 (BS EN 1991) wind and snow loads; a 25-year PPA is an equally long commitment on the money side.

Who each route suits

Buying suits cash-rich, tax-paying businesses that hold their sites long-term and want the maximum return. If you have the capital (or cheap borrowing), pay corporation tax you can offset with the AIA, and expect to own the building for a decade or more, buying almost always wins on lifetime value. It is the right call for most private-sector owner-occupiers — the sort of workplaces covered on our workplace and office car-park canopy page.

A PPA suits organisations that want solar but cannot or will not spend the capital: cash-constrained businesses, and public bodies that struggle to find capital budget. The public sector shows how zero-capital funding works in practice — the Princess Royal Hospital in Telford is building a 200 kW solar car-park canopy backed by £445,000 of Great British Energy funding, projected to save around £35,000 a year, with works from early 2026. GB Energy capital and Salix 0% loans give NHS and school sites zero-upfront routes that mirror a PPA’s cash profile.

The decision framework

Choose to BUY OUTRIGHT if:

• You have capital available, or access to cheap borrowing.
• You are a UK business paying tax you can offset with the £1m AIA — this is the single biggest reason to own.
• You want to keep 100% of the ~10p/kWh generation and all SEG export income.
• You will hold the site for 10+ years, so you capture the near-free power after break-even.
• You want full control to add EV charging, batteries or capacity later.
• Total lifetime return matters more to you than avoiding upfront spend.

Choose a PPA if:

• You have no capital budget and want solar with zero upfront outlay.
• You need the canopy off balance sheet — common for public bodies and capital-constrained organisations.
• You do not pay enough tax to make the AIA worth much (e.g. some charities and public bodies).
• You want a predictable, below-grid electricity rate without owning or maintaining the kit.
• You are comfortable with a 10-25 year contract and the funder keeping most of the saving in exchange for taking all the risk.
• Cash flow certainty matters to you more than maximising the long-run return.

The honest bottom line

For a tax-paying business that can fund the project, buying almost always delivers more over the life of the canopy — you own a 25-year-plus asset, claim the AIA, and keep every unit of cheap generation, accepting an 8-12 year payback for it. A PPA is the right answer when capital is the blocker: it gets solar and covered parking onto your site for nothing upfront and keeps it off your balance sheet, at the cost of handing the funder most of the return. Many public-sector sites reach the same zero-capital outcome through GB Energy or Salix instead of a commercial PPA.

Whichever route fits, the structure underneath has to be built right. We are a turnkey, MCS-certified installer — structure, PV, electrical and DNO connection under one contract, not a bare frame — accredited with MCS, NICEIC, RECC and TrustMark, and backed by an IWA workmanship warranty. If you would like both options modelled against your actual electricity spend, request a free quote or call +44 7707 970661. For a specific application, see our page on EV-charging solar canopies.