I am all electric, three storage heaters and hot water is currently costing me 32 units per night. Without the storage heaters I average 12 units per night. Oven kettle, microwave, TV and computers cost me an average 10 units per day. Following a very large bill caused by a failing immersion...
I have three things.
1 - insurance -check with your company. I changed insurers last month. Most state 'items must be kept in working order'. Specifically, one insurance company wanted a sweep certificate, others did not. Not sure how I would prove I swept my chimney but I do keep it in my diary...