Please do not stint on heat during the cold weather. Power companies are not allowed to cut off vulnerable groups during the winter months, so there is no danger of you being cut off or put on a prepayment meter.
Vulnerable groups include people who are retired, on disability benefits or with children under 5.
Ring your energy company, make sure you are on the 'vulnerable' list. If you think you may have problems with heating billd, contact your energy company before the need arises. Let them know you are struggling.
welbeck, before you turn the heating that low watch this link from the BBC. It shows what happens to your body when you are in a cold room and explains the damage it can do to your health. www.bbc.co.uk/news/health-63602501.
Please get in contact with Age UK tomorrow to ask them what help you can get. I am sure that if you are rationing your heat this much, it must be because you are not claiming all the help you are entitled to. There is a film clip within this link that lists all the money available for older people. Are you getting it all?
Do you have hot water bottles and are you using them? Can you get an electric blanket, whch will help to keep your core heat up. What you are doing is very very dangerous and putting your life at risk. Please contact someone to get help.