Hi,
We have exactly the opposite problem, trying to get
disconnected from the gas supply. A house with Economy 7 heating where the only use of gas is the "convenience" of a gas hob (not even any pilot lights) so the total consumption over the last 10 years has been literally only a few units. Now, the standing charge is over 50p a day for effectively nothing, so numerous requests have been made to quote for the gas to be "disconnected". Occasionally an informal quote has been provided (the first one was actually "no charge") but every time a disconnection is specifically requested, they suddenly discover that their previous answer was "wrong" and the price rises. It's now reached £700 !
There are currently no suppliers who offer even a reduced standing charge (and/or they wouldn't accept a consumer who uses no energy), so it appears that the only solution is to transfer just the electricity (currently a it's dual-fuel contract) to another supplier and then to cancel the gas Direct Debit. Obviously they can have no threat to "cut us off" but we don't really want to be on the wrong side of any Debt Collectors.
Cheers, Alan.