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Power Purchase Agreements explained — without the finance jargon

If the capex of a commercial solar install keeps stalling, a PPA might be the thing. Here's how they work and where they go wrong.

Published Apr 4, 2026 Updated Apr 19, 2026 10 min read
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A Power Purchase Agreement is a way to get solar on your roof without writing a cheque — and without owning the system. Someone else owns it, you buy the electricity it makes, at a rate fixed for 15–25 years.

What a PPA actually is

You lease out your roof space to a developer. They install and own the array. You agree to buy the output at a pre-agreed unit price — typically 30–50% below grid. At the end of the term the system transfers to you, or it's removed, or the PPA rolls over.

Where PPAs beat capex

  • Capex-tight estates where a 6-figure solar bid won't get approved.
  • Tenanted buildings where the payback term outlasts the current lease.
  • Corporate reporting: immediate Scope 2 reduction with zero balance-sheet impact.

Where they fall apart

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