4 ms·

Already kind of in place. I’m on the Octpus agile tariff that gives different electricity tariffs every 30 minutes - with 24 hour notice if tomorrow’s prices.

Already kind of in place. I’m on the Octpus agile tariff that gives different electricity tariffs every 30 minutes - with 24 hour notice if tomorrow’s prices. Whenever electricity prices go negative I have automations to force-charge my solar batteries from the grid, turn on hot water heaters in my hot water tank (normally heated by gas etc. ).

ratherbefuddled 1y ago
Having just had solar and a battery fitted by Octopus I'm interested - would you mind sharing what you use for automation here please?
- Angostura 1y ago
  Sure, I use Home Assistant running in a little raspberry pie in the lift. There is an Octopus Integration that exposes current prices (and much else) to HomeAssistant. There is another Integration that works with my solar panels and another that works with my batteries and can change mode (self use, force charge, force discharge etc.) So from there it’s really just a question of setting up some if-then automations to turn on smart switches, charge the batteries if prices go negative. You can also gradually add more nuanced automations like turning on water heaters if the panels are generating more than 1kW and the batteries are over 90% charged. I’m not a programmer, it’s all fairly easy to do.
  - ratherbefuddled 1y ago
    Thank you, that's really useful.
- jon_adler 1y ago
  Not op but may I suggest looking at Home Assistant, Octopus Energy Addin and Predbat: https://springfall2008.github.io/batpred/energy-rates/ https://springfall2008.github.io/batpred/energy-rates/
  - ratherbefuddled 1y ago
    Thanks very much.
ragebol 1y ago
To add, so called 'dynamic energy contracts' are getting more and more popular, at least in my native Netherlands. The European day-ahead electricity market switched to 15-minute price blocks this month, to more accurately follow the supply and demand. The market for power imbalance was already on 15 minute blocks. I'm using a HomeWizard smart plug [0] to enable my electric boiler to only run during the cheapest hours of the day [0] https://www.homewizard.com/energy-socket/ https://www.homewizard.com/energy-socket/
cameronh90 1y ago
I do similar, but without the batteries. I just have Home Assistant turn on everything: dehumidifiers, heaters, lights, set the freezer thermostat to -25c. So far I've earnt about 10p, but the real saving comes from having a little bit of thermal inertia to carry through to when prices are higher.
corint 1y ago
You might find the crossover for hot water heating is higher than 0p; your boiler is likely only around 70% efficient. So at 6p/therm for gas, you'd break even with resistive electric heating at around the 10p/kWh mark. You should absolutely re-run these numbers to be sure, but you might find you can use electric heating far more often than you might currently be doing.

ratherbefuddled 1y ago

Having just had solar and a battery fitted by Octopus I'm interested - would you mind sharing what you use for automation here please?

Angostura 1y ago
Sure, I use Home Assistant running in a little raspberry pie in the lift. There is an Octopus Integration that exposes current prices (and much else) to HomeAssistant. There is another Integration that works with my solar panels and another that works with my batteries and can change mode (self use, force charge, force discharge etc.) So from there it’s really just a question of setting up some if-then automations to turn on smart switches, charge the batteries if prices go negative. You can also gradually add more nuanced automations like turning on water heaters if the panels are generating more than 1kW and the batteries are over 90% charged. I’m not a programmer, it’s all fairly easy to do.
- ratherbefuddled 1y ago
  Thank you, that's really useful.
jon_adler 1y ago
Not op but may I suggest looking at Home Assistant, Octopus Energy Addin and Predbat: https://springfall2008.github.io/batpred/energy-rates/ https://springfall2008.github.io/batpred/energy-rates/
- ratherbefuddled 1y ago
  Thanks very much.

ragebol 1y ago

To add, so called 'dynamic energy contracts' are getting more and more popular, at least in my native Netherlands. The European day-ahead electricity market switched to 15-minute price blocks this month, to more accurately follow the supply and demand. The market for power imbalance was already on 15 minute blocks. I'm using a HomeWizard smart plug [0] to enable my electric boiler to only run during the cheapest hours of the day [0] https://www.homewizard.com/energy-socket/ https://www.homewizard.com/energy-socket/

cameronh90 1y ago

I do similar, but without the batteries. I just have Home Assistant turn on everything: dehumidifiers, heaters, lights, set the freezer thermostat to -25c. So far I've earnt about 10p, but the real saving comes from having a little bit of thermal inertia to carry through to when prices are higher.

corint 1y ago

You might find the crossover for hot water heating is higher than 0p; your boiler is likely only around 70% efficient. So at 6p/therm for gas, you'd break even with resistive electric heating at around the 10p/kWh mark. You should absolutely re-run these numbers to be sure, but you might find you can use electric heating far more often than you might currently be doing.