"1MW will power 700,000 homes, yes 700,000"?
Wow, I need some of Harry's energy-saving lightbulbs.
1MW / 700,000 homes = 1.43W.
1.43W x 365 days x 24 hours/day = 12,500Wh = 12.5kWh.
1kWh (1 unit) costs about 15p on average, so according to Harry the average electricity bill should be less...