The short answer
Is buying solar or a funded PPA better for our garden centre?
Buying and an onsite power purchase agreement create different ownership, payment and long-term obligations. Neither is automatically best. Compare site-specific costs and contract terms over the same period, including energy payments, maintenance, price changes and what happens when the arrangement ends.
Buying solar and a solar PPA compared
| Consideration | Buying solar | Solar PPA |
|---|---|---|
| Ownership | Confirm the owner and any lender’s rights under the purchase and finance agreements. | Confirm who owns the system during the term and what rights the centre receives. |
| Payments | System purchase cost, or finance repayments, plus costs not included in the package. | Contracted electricity payments and any other agreed charges; check indexation and purchase obligations. |
| Operation | Check who provides and pays for maintenance, insurance, monitoring and replacements. | Check the provider’s duties, exclusions, performance terms and the centre’s responsibilities. |
| Property changes | Check finance restrictions, warranties and costs of relocation or roof works. | Check roof rights, lease alignment, transfer, early termination and any buyout terms. |
| End of term | Plan for continuing operation, replacement or removal and any outstanding finance. | Confirm the actual expiry options, ownership position, removal duties and costs. |
Understand what you would be paying for
With a purchase, the business pays for the system, using its own funds or separate finance. Ownership gives it the benefit and responsibilities set out in the supply, finance and maintenance agreements. A financed purchase still has repayments and financing costs.
In a typical funded onsite PPA, another party owns the solar equipment and sells electricity under a contract. A proposal may reduce or remove the customer’s upfront system cost, but it is not free electricity. Check all charges and commitments in the actual offer. Funding availability and terms depend on suitability and agreement.
Compare more than the first-year saving
Use one demand forecast and one comparison period for both options. Show upfront expenditure, energy purchases, other charges, maintenance, insurance, financing and replacements where applicable. Identify which costs are included and which the centre would still pay separately.
Test different electricity-price and consumption scenarios. A contract rate that changes over time needs to be modelled that way. Ask how exported, unused or curtailed generation is treated and whether any minimum purchase or other payment obligation applies.
Read the property and operating obligations
The roof is part of an operating business. Establish access rights, roof repair arrangements, responsibility for removing and reinstalling equipment, and the effect on insurance. Check who responds to a fault, maintains the system and bears the cost if performance is lower than expected.
If the centre is leased, the landlord’s consent and the lease must work with the proposed solar agreement. A sale, move, redevelopment or lease expiry may affect the arrangement. Do not assume you can transfer, terminate or buy out a contract without a cost or consent.
Make the end of the agreement explicit
Ask what happens at normal expiry and on early termination. Potential outcomes include removal, an extension or a purchase, but the actual contract decides what is available and at what cost. Record who owns the equipment, who can claim the renewable-electricity benefits, and who receives any export income.
Have the site-specific agreement reviewed by the business’s legal and financial advisers before signing. An educational comparison cannot establish the accounting, tax or legal treatment of a particular contract.
Use the right measure for each route
For a purchase, capital payback can be one measure alongside whole-life cash flow, risks and operating responsibilities. For a funded PPA, compare the customer’s cash flows and obligations against the alternative electricity supply. The funder’s investment is not the customer’s capital expenditure.
Keep a battery and any flexibility or trading arrangement visible as separate parts of the proposal. They can change the operating and commercial position; they should not be hidden inside a single headline solar saving.
Check the detail
Sources & further reading
- SSE Energy Solutions: distributed generation and storage (opens in a new tab)
A provider’s explanation of its ownership and PPA payment model. It illustrates a funding structure, not a partnership with TEE or the terms of a TEE offer.
- Solar Energy UK: a corporate buyer’s guide to onsite solar (opens in a new tab)
Background on commercial solar routes. The guide’s historic market figures are not a TEE price or current offer.
- North Herts Council: Solar for Business FAQs (opens in a new tab)
A dated 2024 pilot FAQ illustrating the property, payment and contract questions buyers need to ask. Its deadline, eligibility, rates and term are not a current TEE offer.
Links and guidance checked 29 October 2026.