Please make absolutely sure thay you know the Economy 10 times being used by your meter. They differ in some parts of the company. Treat any times given to you by your supplier with scepticism, especially if it’s SSE, who either don’t know or give you a meter for the wrong area and the wrong times. If necessary, hang around at changeover times to make absolutely certain that the meter is switching tariffs at the correct time. My meter goes click and a number changes on the display from 1 to 2 or back again.
As an example, here are the times operating in North Shropshire, which are definitely not the same as elsewhere:
4:30am – 7:30am
1:00pm – 4:00pm
8:30pm – 00:30am
I recommend the ‘Meter Readings’ iPhone/iPad app by Graham Haley for keeping track of peak and off-peak usage and costs over time. I now have five years’ worth of readings and it’s a helpful graphical check on how disciplined you are being at using off-peak and whether your supplier is raising prices faster than they ought. The way SSE made mistakes, raised prices and generally messed me around was carefully recorded and eventually persuaded me to move to OVO – but only after I had found this website that confirmed for me that it was actually possible. The graphs of my costs per month are now plummeting since I have moved, especially the off-peak one.