The UK pays people not to use electricity?

For a few hours this week and until the end of winter, UK residents can earn money by turning off the lights, unplugging laptops from the mains and using the microwave to warm up lunch, rather than cooking it in an electric oven.

National Grid, the UK's electricity system operator, is teaming up with energy companies to offer payments via electricity bills to customers who use less electricity during certain "savings sessions." 

?"Saving sessions" are time intervals that occur during peak electricity demand hours, for example, in the morning and evening, when people are preparing or returning from school and work, watching TV, turning on lights and electric heaters and cooking. 

Payments vary, but they can reach about 4 pounds ($10) per kilowatt-hour of energy saved, compared to the average household consumption.

A similar reward system also works as an experiment in California, USA.?