The Warm Home Discount Scheme is mainly available to pensioners who get a form of Pension Credit. But, some - not all - suppliers also give it to a "broader group" including those on certain benefits and people on low income who have an illness.
It's worth checking out. I just qualified under the broader group with Sainsbury's Energy (part of British Gas) britishgas.co.uk/warmhomedi...
This is the first time I've qualified as I used to be with a different energy provider who had different rules for their "broader group". I'm a happy bunny this year, maybe you could be too?