We are in the process of buying a new house and will be renting out our flat when we finally move. We are quite high energy users - both work from home - long days on the computer then the kids come home from school, and another two PCs get switched on for homework and gaming etc. we have high energy bills but I understand why and just accept it. However, when our tenants move in, and take over the gas and electric, does the fuel company work out their direct debit based on our previous usage? I know it would adjust to reflect their usage eventually but I feel they’ll have quite a scare if their first bills are as high as ours. So does the fuel company start from scratch or is it based on the historical use at the property?