Octopus Energy paid out more than £1 million to its customers for cutting down on their energy usage on Tuesday evening and helping reduce the strain on the power grid.

The energy supplier said that more than 400,000 customers took part in the challenge between 4.30 and 6pm.

The average customer was paid £2.50 in special points, which entitles them to rewards, reducing their demand by around 60% on average while the top 5% were paid an average of £15 in points.

Customers were paid 3,200 OctoPoints per kWh reduced, equivalent to £4.

Octopus said the initial data showed it had reduced the UK’s energy usage by around 250MWh, the same as the city of Liverpool going off grid for one hour.

The company said participation on Tuesday was similar to Monday, but as Tuesday’s event was higher paying, and there was 30% more energy reduced than the night before, less than £1 million was paid out on Monday, although it did not have the exact figure.

Octopus is the most active in the new scheme, which pays customers to switch off appliances.

The so-called Demand Flexibility Service was launched by National Grid’s Electricity System Operator (ESO) to help reduce peak demand during times where supplies are tighter than usual.

Several other energy suppliers took part in the system, which went live for the first time on Monday evening. It had been tested on several occasions previously.

By asking households to help out by using electricity at slightly different times to usual, the grid does not have to pay very expensive power plants to come online and produce more power.

The households who take part in these sessions can still use as much electricity as normal, but by doing it later or earlier they can help out, and save.

Experts see it as the first step towards a system where smart technology in people’s homes helps to switch usage to off-peak times, saving households money and taking pressure off the grid.