I listen to a lot of radio 4 consumer and money programs.
Whenever they do phone ins on reducing energy consumption there are several callers that say this almost word for word "I'm doing everything I can to reduce my bills, I turn the lights off when I'm not in the room, not leaving the TV on standby, only filling the kettle with enough water for the cup"
Modern bulbs now cost c.£20 a year to run, TV on standby doesn't cost a lot either.
My partner has a bad habit of putting about half a cup less than needed in the kettle and needs to boil the kettle twice which is more annoying and probably costs more than boiling an extra cup.
People don't mention insulation, changing room temperature changing the way they cook, temperature of water, setting for the radiators, length and frequency of shower, washing clothes only when dirty rather than daily...
We do tumble down meals to save money/time/energy. We cook a joint of meat twice a week and use that for several days in different meals. We either roast it or slow cooker it on the first day then turn it into quick meals that can be made in 10 minutes on the subsequent days either quickly on the hob or in the microwave so much lower costs than having the oven or slow cooker on every day. If I have had the oven on I leave the oven open to warm the room.
I haven't turned the heating off since we moved into the house in 2022!* If the house feels cold and it's 17-18 degC I'll pop it on at 19degC for an hour or so. If I feel cold I check my clothing and have a drink, get a blanket and put the heating on if I continue to be cold. We have fans under some of our radiators to improve their efficiency, we have no furniture infront of any of our radiators, all of our rooms have blinds and curtains which are closed as soon as it gets dark. We make sure we dust the radiators where we can and bled to make sure there is no air settled in the radiator, check for excessive sludge too - our previous house had cold radiators as they were full of sludge that we had to flush out to get them working again.
*Thermostat is set to 14degC overnight and 17-17.5degC during the day. I don't care if it's May or September if it's 17degC I'd want the heating on.
I changed the settings on my parents radiators last winter. There house was either roasting or freezing. All the radiators were set to maximum. I went around and lowered the downstairs radiators to 3-4 and upstairs to 2-3 and they were then able to easily maintain a steady temperature and it dropped the energy use too.