PPAs — how long-term contracts financed the renewable boom

A Power Purchase Agreement (PPA) is a 5–20 year bilateral contract between a renewable generator and a corporate or utility offtaker that locks in a fixed or indexed power price. It's the funding instrument behind most of Europe's renewable build-out from 2020 onwards: banks lend against the future revenue, the seller secures the cash flow to finance the project, and the buyer gets predictable electricity costs and a green claim.

In 2023, European offtakers signed PPAs for roughly 16 GW of new renewable capacity, according to Pexapark. About 12 GW of that came from corporate buyers — Microsoft, Amazon, Google, a handful of carmakers, and a long tail of food and retail groups locking in their next decade of power bills. The rest came from utilities. Either way, it is more renewable capacity than most EU countries added in total.

A PPA is a long-term bilateral contract for electricity, usually between a renewable generator and a buyer called the offtaker. Terms run 5 to 15 years, sometimes 20. The contract fixes a price, or a price formula, well outside the horizon of any spot market or exchange-traded future. That single feature is why PPAs financed most of the wind and solar built in Europe over the last decade.

There are two flavours. A physical PPA delivers actual electrons: the generator sits inside the buyer’s balance group, or a utility sleeves the volume through. A virtual PPA, also called a financial PPA or contract-for-difference, is a swap. The generator keeps selling its output into the spot market. Separately, the contract pays the difference between an agreed strike price and a market reference, typically the day-ahead spot for the relevant bidding zone. The economic outcome is the same: both sides have locked in a price, regardless of where spot goes.

Developers love PPAs because a 10-year contract with a creditworthy offtaker makes a project bankable. Banks lend against contracted revenue, not against forecasts of what Nord Pool might do in 2032. Buyers love them because they get long-term cost certainty and a credible additionality story for their sustainability reports. The boring truth is that the offtaker’s credit rating sets the cost of capital for a wind park, which decides whether the project gets built at all. PPAs probably did more to fund the European energy transition than any subsidy regime.

The real work in a PPA is risk allocation. Price risk goes to whoever holds the wrong side of the strike. Volume risk, what happens when the wind does not blow, is usually the generator’s. Basis risk, the gap between the asset’s actual location and the reference price, is a perennial argument. Curtailment, grid charges, regulatory and tax changes all need a clause. The virtual-versus-physical distinction matters less than the fine print on these allocations.

Compared with power futures, which are exchange-traded, standardised and rarely extend past three years, PPAs are bespoke, illiquid and long. Futures hedge a quarter. PPAs underwrite a power plant.

The Estonian PPA market is younger than the German or Nordic ones, but it is moving. Volton is not a PPA originator; those deals are structured by banks, specialised brokers and the buyer’s own energy desk, with industry pipelines tracked on platforms like RE-Source. What we do see, often, is a generator or large consumer that already sits under a PPA and asks what else their asset can earn. That is where we come in: a PPA fixes the baseline price, and we layer flexibility and balancing revenue on top of it.