Comparison

PPA vs Roof Rental

Solar PPA vs renting your roof to a generator. Two very different deals — PPA buys cheap power, roof rental gives you a small annual fee.

Side-by-side comparison

	Solar PPA	Roof rental / hosting
What you get	Cheap kWh (11-16 p)	Cash rent (£5-15k/MWp/year)
Power	Yes — for your business	No — exported to grid
Risk profile	PPA performance risk on provider	Tenant risk on rent payer
Term	15-25 years	20-25 years
Best for	Sites that use the kWh	Roof-rich, low-power-use sites
Both possible?	—	No — pick one

When Solar PPA wins

Solar PPA typically wins when (a) you need zero upfront capital, (b) you want operations and performance risk transferred, (c) your business horizon doesn't extend to a 25-year capital commitment, or (d) you want speed to deploy.

When Roof rental / hosting wins

Roof rental / hosting typically wins when (a) you have capital and want the lowest 25-year cost, (b) you want to retain ownership of the asset and its long-term value, (c) you can manage operations in-house, or (d) you're constrained by structural reasons (e.g., procurement rules for public bodies).

FAQs

Comparison FAQs

Which option should I pick?

Roof rental gives you ~£5-15k/MWp/year in cash but no power. PPA gives you 30-50% cheaper electricity. Pick based on whether you use the kWh. Run your specific numbers in our PPA calculator before deciding.

Can the two be combined?

Sometimes. SEG income always layers on top of either route. AIA / Full Expensing combine only with cash or self-finance. PPA + grant rarely stack — most grants exclude PPA structures.

Where can I read more about the underlying mechanics?

Our mechanics hub covers 10 deep-dives on PPA structure, pricing, escalators, term, end-of-contract, off-taker covenant, EPC, O&M and M&V.