Commercial PPA vs Ownership Calculator
Two ways to go solar as a business: buy the system, or buy the power. Compare 20-year costs of a PPA against ownership with the tax credit.
energy payments
net capex + O&M
same energy, 3%/yr escalation
vs PPA over 20 years
Results update live as you type. For planning and field-check estimates — always verify against applicable standards and equipment ratings.
Buying the system versus buying the power
A power purchase agreement puts the system on your roof at zero capital cost: a developer owns, operates, and maintains it, and you buy the output at a contracted rate — typically below your utility rate on day one — with an annual escalator of 1–3%. Ownership flips the structure: you fund the capex (often $1.30–2.00/W at commercial scale), capture the 30% investment tax credit and accelerated depreciation directly, and keep every kWh at zero marginal cost for the life of the equipment.
The pattern the numbers usually show: PPAs win on simplicity, balance-sheet treatment, and transferring performance risk; ownership wins on total 20-year cost, often by a wide margin — provided the business has the tax appetite to use the credit and depreciation, which is the single most common deal-breaker. Nonprofits and low-tax entities lean PPA (or explore direct-pay provisions) for exactly this reason.
Watch three contract details on any PPA: the escalator compounding against your actual utility trajectory, the buyout schedule if you later want the asset, and end-of-term removal or renewal obligations. Everything in a commercial PPA is negotiable — the first term sheet is an opening position, not a market price.