Time of Use Tariff Saves Me Money

  • wizzo227's Avatar
    Level 22
    @geoffers
    Thanks. It was quite satisfying to see that the electricity wholesale price at Nordwhatsit (£/MWh) closely resembled the retail price which I pay, with passthrough of the near-nil price hours during the windy weekend of 20th-21st October. Intermittent renewables are going to do that; they don't always conveniently fit the Economy-7 timetable of 40 years ago, so we should want methods in place to exploit the windy hours whenever we can. passthrough of near-nil prices by the half-hour did work for me to get my house to preferentially use near-nil CO2 electricity last week.

    I noticed that on the deal which I'm on, 4-7pm is consistently always most expensive, so between those times I use less than I usual. For example no cooking in the big oven, heat pump and room heaters OFF between those hours.

    When I was 4 years old, my Mum worked out a good trick to tell us that "the telly doesn't work" at particular times of the week, notably Saturday mornings. She'd secretly switched it off at the wall, and we weren't allowed to touch the switch at the wall. Could that approach help economiser households ?
  • wizzo227's Avatar
    Level 22
    Well, the bill is in for the past month. And the average number is ...

    Name:  bill23oct2024.jpg
Views: 52
Size:  30.0 KB
  • wizzo227's Avatar
    Level 22
    The all October price records from the other place who do by-the-half-hour electricity are as pictured (possibly except for the last point in October. My especially fiddly computer program might have missed a bit?)

    Name:  PriceOct24.jpg
Views: 9
Size:  51.1 KB

    Summing 1490 prices x quantities over the month, I'm estimating that electricity units cost me about £15.63.02 in October and averaged about 17.1 p/kWh incl.
    From the chart one sees times almost every day in October when electricity costs more than twice that much, which is usually at the evening peak time, so that is when I avoid using anything big. The near nil prices were on usefully windy days in October. You get a day's notice to schedule things to use up some of that, and it is usually obvious to be likely from the weather forecast too. An economy-7 schedule could have hit probably 2/3 of the bill savings which I got but isn't as good because economy-7 does not ever seek or reward times when there are plenty of renewables like this pricing does.