What's actually happening with renewables? Hype, revolution, or both?: Grid realists

6:47 PM

At 6:47 PM on September 8, 2020, the California Independent System Operator ordered rolling blackouts. Temperatures above 110 degrees. Air conditioners at maximum. The sun was setting. Solar dropping toward zero. Wind negligible. Two million people lost power.

The 2021 Texas freeze killed 246 people. The physics are not a talking point. Electricity must be generated at the instant it is consumed. There is no warehouse. When supply drops below demand, the frequency deviates, equipment trips, and the cascade begins.

The four-hour battery

The optimists show us cost curves. Solar in West Texas bids at $15 per megawatt-hour — between 10 AM and 4 PM on a sunny day. At 7 PM, the bid is zero. The market-clearing price at 7 PM is five to ten times the midday price, because the only generators available are natural gas turbines that were told they were being retired.

The largest grid battery stores roughly four hours. The European Dunkelflaute — a German energy-industry term for extended periods of cold, cloudy, windless weather when solar and wind output collapses simultaneously — routinely lasts seven to fourteen days. Covering a three-day Dunkelflaute for Germany would require 45 terawatt-hours of storage. Germany has approximately 0.01 installed. The gap is three orders of magnitude.

France generates 70 percent of its electricity from nuclear. Grid emissions roughly one-fifth of Germany’s per kilowatt-hour. Germany shut down nuclear, replaced it with renewables and — when wind wasn’t blowing — coal and Russian natural gas. Germany’s electricity costs roughly three times France’s. The nuclear advocates have the empirical comparison, and it is not subtle.

The transition realists start from what has actually happened rather than cost projections. Every transition was an addition. Intermittent sources cannot replace dispatchable ones one-for-one. No cost reduction changes the physics of a rotating grid.

Where we concede ground: We conflated intermittency is real with renewables can’t be large. Grids at 30-40 percent variable penetration are operating reliably.

What would change our mind: A major industrial grid operating at 80 percent variable renewables for five years without fossil backup or stability events.

Read the full synthesis: What’s actually happening with renewables? Hype, revolution, or both?