Half hourly prices for your postcode, two years back and thirty six hours forward. Your meter tells us what the building did with them.

Compressors, kilns and heat pumps move their duty cycle by up to four hours. Nothing in the building changes temperature, so nobody in it notices.

The difference between the hour you would have bought and the hour we bought lands as a credit, not as a discount on some later bill.

Every shifted cycle carries a timestamp, a price and a kilowatt hour. Your auditor reads the same file we do.