Negative electricity prices, explained
On a windy or sunny day, Britain can generate more electricity than it needs. Some generators are paid per unit produced, so they would rather pay someone to take the power than switch off. When that happens the wholesale price drops below zero.
Tariffs that follow the wholesale market, such as Agile Octopus, pass this on. A negative price means you are credited for every unit you use in that half hour.
How often does it happen?
Across all 14 regions there were 1399 negative half hours in the last 30 days, roughly 50 hours per region. They cluster on windy nights, weekend afternoons and sunny spring and summer days.
Who can benefit?
- Households on a half-hourly tariff such as Agile Octopus, with a working smart meter.
- Anyone who can move flexible use: charging an electric car, a home battery, running the washing machine or dishwasher, heating hot water.
The catch
Agile prices can also spike at teatime, so it suits people who can avoid the 4pm to 7pm peak. Always compare with your current tariff before switching.