At any istant in time, power grids operators struggle to balance the quantity of electricity demanded and generated. Sudden, unanticipated, nation-wide surges or drops of demand create unbalance in the system and if no immediate reaction on the generation side takes place, service interruptions happen. To avoid this, fast pumped-storage hydroelectric plants generally kick in first, followed by slower fossil fueled and nuclear plants.
Do these unanticipated large changes in demand really exist? At least in the UK, yes, and surprisingly TV is to blame. Per se, TV represents only between 5 and 8 percent of the world’s residential electricity, and in terms of instantaneous power gives no real concern to the grid with its modest load around 100 W. The problem, called TV pickup, is that some programs are followed by millions of British citizens, who in the commercial breaks likely activate their kettles simultaneously, loading the grid with around 1200 W each for a couple of minutes, and causing surges of thousands of MW nation-wide. Especially when the break schedule is not fixed ahead, like for sports events, this can lead to either blackouts or carbon-intensive power generation.
How to avoid these problems? A first option is investing more in costly power storage technologies. A second one focuses on less costly demand management programs and devices, making people aware of their consumption and responsive to incentives aligned to the needs of the grid. A simpler, third option against TV pickups also exists, and is called “book pickup”.