I know smart meters have a bad reputation, but since we got one I can access via my supplier’s website hourly consumption data in KWh for each day of the month, which does help track down where the power goes. For example if you know you had the oven on for an hour, or the tumbledryer, etc then by comparing the consumption with the previous day you can see exactly how much was used.
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For lowering overall consumption my top tip is to kill the standby power. Everyone thinks first of the high power devices like washing machine, fridge, etc.. but it’s those things which sit there 24/7 using a small amount which tick the meter higher that you can do something about. The TV and all those little set top boxes with their LEDs on all night and all day are using more than you think even when you don’t use them. I got an “EON powerdown” for £6.99 from Amazon years ago which lowers the standby consumption to only 0.5W - little things like this do help.