The law that created the independent power industry.
The Public Utility Regulatory Policies Act of 1978 was, on its surface, a modest piece of legislation. It directed FERC to set rules for "Qualifying Facilities" — small power producers using renewable energy or cogeneration (the simultaneous production of heat and electricity). But hidden in its provisions was a nuclear bomb aimed at the heart of utility monopoly.
The bomb: utilities were required to purchase power from QFs at "avoided cost."
Avoided cost meant what the utility would have paid to generate or purchase that power itself. If a utility's marginal cost of generation was $40/MWh, it had to pay any qualifying independent generator $40/MWh for every kilowatt-hour they could produce. The utility couldn't say no. The utility couldn't negotiate. The QF had a legal right to interconnect and a legal right to be paid.
Calculating avoided cost turned out to be enormously contentious. Was it the utility's short-run marginal cost (the fuel cost of the last generator dispatched)? Its long-run marginal cost (the cost of building the next power plant)? Some states, particularly California, went with long-run avoided cost — which, in the early 1980s with nuclear plant costs spiraling, was very high.
California's Standard Offer 4 contracts, adopted by state regulators in 1983, locked in avoided cost payments at a fixed rate of around 6.5 cents per kilowatt-hour — regardless of what actually happened to fuel prices. It seemed reasonable when oil was $35 a barrel. When oil fell to $15 a barrel in 1986, utilities were suddenly obligated to buy expensive QF power that was far above market. The avoided cost calculation had produced an avoided cost crisis.
Despite its implementation problems, PURPA quietly built the infrastructure — legal, financial, and technical — for a competitive power industry. Investment bankers learned to finance power plants. Lawyers developed contract templates. Engineers designed projects around independent ownership. The QF industry proved, beyond any reasonable doubt, that someone other than the regulated utility could finance, build, and operate a power plant reliably.
This was PURPA's deepest legacy. It didn't just create a market for independent generators. It disproved the foundational assumption of the vertically integrated monopoly: that generation required monopoly ownership to work.
California, September 1983. The California Public Utilities Commission issued its "Standard Offer 4" contracts: long-term purchase agreements paying independent generators a fixed 6.5 cents per kilowatt-hour — locked to projections of continually rising oil prices — for periods up to thirty years. Developers flooded in. Wind farms and geothermal projects sprouted across the state. Then oil prices crashed in 1986, falling from $35 to below $15 a barrel. The utilities were still contractually bound to pay the old SO4 rates for years, sometimes decades, into the future. PG&E, Southern California Edison, and SDG&E collectively faced billions of dollars in above-market payments, funded through ratepayer surcharges. The SO4 experiment demonstrated both what PURPA intended — genuine independent power production at scale — and what its avoided-cost framework could not handle: a world where fuel prices moved down as well as up.
NREL — California Standard Offer 4 contracts background CPUC Decision background