For twenty years, going solar meant buying the power plant on your roof: a big loan, a long payback, and all the responsibility. Everyone wanted the savings. Nobody wanted the debt.
In 2025, the market moved. Federal incentives shifted away from homeowner-purchased systems and toward the companies that fund, own, and maintain them. Those providers now compete for qualified roofs, and it is why most new home solar in America is now third-party owned.
The short version: TPO tells you who owns the equipment. The provider funds, owns and maintains the system, while the homeowner uses the solar energy it produces. The specific agreement then determines how the homeowner pays.