National Grid is preparing for a 400MW spike in demand on Saturday (13 August) as people tune in to watch Olympic athletes compete for gold medals.

The higher-than-usual demand is expected as people stay up until 3am on ‘Super Saturday’ to watch Jessica Ennis-Hill, Mo Farah and Greg Rutherford compete. The prediction is lower than the 2012 Olympics in London, which National Grid attributes to the time difference in Rio.

A ‘TV pickup’ is an increase in demand seen during advert breaks or at the end of popular programmes as consumers switch on electrical appliances and lights.

Grid is expecting a pickup of 500MW during the tennis event, if Andy Murray makes it to the final at around 8pm.

If the women’s gymnastics team reach the final round, Grid said it predicts a 250MW spike.

Britain saw another pickup of around 169MW when Tom Daley won a bronze medal on Tuesday night, but this is much less than the predicted 350MW. A further increase of 50MW was seen when the coverage switched to gymnastics.

National Grid energy forecasting manager Jeremy Caplin said: “The pickups during this Olympics so far have been lower than London 2012 which is probably due to the time difference as most of the events happen overnight.

“As always our team of experts in the control room are working hard to ensure our predictions are as accurate as possible and we are expecting to see an increase in demand of 200MW overnight during ‘Super Saturday’ as people tune in to watch stars such as Jessica Ennis-Hill and Mo Farah.”