I am going to create a smart switch to shut of my two biggest electricity consumers; my electric boiler and car. This will be done with a Raspberry Pi-ish device and a solid state relay. Might even throw in a mosfet for switching the relay.
The picture shown above is a custom status page I made for viewing my electricity consumption and hourly prices. And I can access this information, so can a tiny computer controlling a relay.
My car and boiler however each have a different usage profile, so I actually will make the same device twice but with different settings.
When I get home from work, I have about 14 hours to charge up my car. I want to use the cheapest 3 to 7 hours to charge it.
Have a look at this picture to see what I want to do. The first hours are the cheapest and almost guarantied to be used. The less cheaper hours after that are less likely to be used. The problem is this. How do i describe this in terms of software? And what if the cheap spot is not in front? Do we cut charging up in multiple zones. I guess we will have to find out.
The electric boiler I only use for showering, at the most expensive time possible, like all the other people in my country, which is why it is so expensive in the first place. Boiler must not be switched on at that time period.
Then for (re)heating the water back up again. This will fairly simple I guess, just find the 4-6 lowest prices and switch the boiler on at those times. Should work just fine right?