Octopus Agile negative prices: what should your battery do?
On 36 days in the last year, Octopus Agile paid people to use electricity: 246 hours below zero in North West England, as low as −11.67p a kWh. A battery with room is paid to fill, then saves the dearest power of the day.
What these figures rest on: the prices Octopus published for Agile and Agile Outgoing, all 14 regions for the counts and North West England for the rest, 1 November 2025 to 31 October 2026. No home is modelled; a stored kWh loses the 17.9% one real home measured going in and out. How Orza is tested.
Below zero on 36 days in a year, in every region.
Agile’s prices are set for each half hour from the wholesale price, and when that falls below zero, so does Agile. Every one of Octopus’s 14 regions went below zero on 35 or 36 days, for about the same number of half hours.
Agile, 1 November 2025 to 31 October 2026
- 246 hours below zero in North West England492 half hours. Every region had between 461 and 499.
- As low as −11.67p a kWh12:30 on Sunday 5 April 2026, in a run of 17 hours below zero. The lowest anywhere was −12.83p, in North Scotland.
- −3.22p on averageMost half hours below zero pay a few pence, not tens.
Orza fills your battery when Agile pays you to, and keeps it for the evening.
Free, with no card: an email and a password, and you look round an example home first. Connect your battery through its maker’s cloud when you’re ready, or never. It starts in Monitor only, and nothing is sent to it until you choose.
Middle of the day, April to October, mostly at weekends.
The half hours below zero in North West England over the year, by time of day, month and day of the week.
- Two in three between 10am and 4pm323 of the 492 half hours started between 10am and 4pm. Another 112 came between midnight and 8am, and almost none in the evening.
- April and September most of all144 half hours in April and 131 in September, then 69 in July, 62 in June and 50 in October. There were none in November, January, February or May, and two in December.
- 23 of the 36 days were a Saturday or a Sunday12 Saturdays and 11 Sundays, against one Monday and one Tuesday.
- Known the afternoon beforeOctopus publishes the next day’s Agile prices each afternoon, usually between 4pm and 8pm, so a day below zero is never a surprise to anything that reads them.
Agile Octopus (AGILE-24-10-01) prices as Octopus published them, with VAT, 1 November 2025 to 31 October 2026, times in UK clock time. North West England unless another region is named. Read 1 November 2026.
Have room when it starts, fill, and keep it for the evening.
On 31 of the 36 days the cheapest four hours averaged below zero, so a battery could fill without paying anything at all. What that charge is worth depends on when it comes back out.
On the 36 days below zero
- A kWh stored then saved 31.77p in the eveningFilled in each day’s cheapest four hours and used from 4pm to 7pm, after the 17.9% a battery loses going in and out. 18.30p to 46.82p a kWh, against 20.35p on an average day of the year.
- Selling then earned almost nothingAgile Outgoing averaged 1.27p in the same half hours, and never paid more than 2.62p. Sun is worth far more stored than sold on these days.
- A battery that is already full misses itA battery filled overnight, or by morning sun, has no room left by midday. Running the house from it in the hours before makes the room to be paid for.
Orza plans for it the day before, from Octopus’s own prices.
Orza reads each day’s Agile prices as soon as Octopus publishes them, with your solar forecast and how your home uses power, and plans your battery 36 hours ahead, again every half hour.
On a day below zero, it
- Makes room firstIt runs the house from the battery in the hours before, so there is space when the price drops.
- Fills in the half hours that pay mostNot simply the first one below zero, but the ones that pay the most, up to what the battery can take.
- Keeps the charge for the peakAnd it tells you, in plain words, why it did each thing.
Before the next day below zero.
What changes the answer for your home.
All our guidesGet more from your battery
How Orza is tested
Why do Agile prices go below zero?
Agile follows the wholesale price of electricity, half hour by half hour. When wind and sun produce more than the country is using, the wholesale price can drop below zero, and Agile passes that on. That is why it clusters in sunny, breezy middays, and at weekends, when less is being used.
Does Agile Outgoing go below zero too?
Not in this year. In North West England it never went below zero, and in the half hours when Agile was below zero it averaged 1.27p.
Will my battery charge from the grid on its own?
Usually not. Left to itself, most batteries fill only from spare sun, so they miss a day below zero unless a schedule or a planner tells them to charge from the grid. When a summer grid charge is worth it.
How do I know when one is coming?
Octopus publishes the next day’s prices each afternoon. We post each day’s cheapest and dearest hours for London on X and Facebook once they are out, and Orza plans your battery from them automatically.
Can a battery with no panels use these days?
Yes: it fills from the grid like any other. Over a year of prices, a 9.5 kWh battery with no panels filled on Agile and sold on Agile Outgoing made £134.78. A battery without solar, over a year.
What does Orza cost?
Nothing right now: everything is free while we spread the word, and no card is needed to join. Paid tiers will come later, and there will always be a free version.
Paid to fill, planned the day before, for your own battery.
Free, with no card. Look round an example home first, and connect your battery when you’re ready.