When power costs less than nothing
Sometimes there's so much wind and solar, and so little demand to soak it up, that the wholesale price falls below zero — producers pay to keep generating. Wattlas treats this as a first-class metric: how many hours a year, when they cluster, and how long each spell lasts.
Negative hours have climbed as wind and solar have grown. Each bar is a full calendar year; the current year is shown to date (YTD) and isn't comparable to a finished one. Use the selector below to zoom the day-by-day calendar into any year.
Each cell is one day; the colour shows how many hours cleared below zero (pale = none). Negative days cluster in sunny, windy stretches.
A short dip is easy to ride through; a long one is what hurts. As midday solar grows, the negative spells stretch from an odd hour into long, continuous runs.
Negative prices are largely a spring-and-summer story: long days, strong sun, mild demand. Dark winter months barely register.