::: nBlog :::
I recently switched our electricity provider and got a new contract that supports hourly pricing, which means that every hour has a different price tag per kilowatt-hour.
Here in the Nordics the electricity market has been somewhat open for the last 15 years, and there’s a marketplace called Nordpool where buyers and sellers of electricity trade their kWh’s in a stock market – like fashion.
There is, though, one major difference to a real stock exchange: Tomorrow’s prices are known today, giving utilities a lot of room to adjust their production to most profitable times.
So without adding any hardware, I decided to create an algorithm that estimates our electricity usage for the next day and picks the cheapest hours for most consumption. This is possible due to our battery bank which can store about 50 kWh and which can support the house for 2-3 days without external power.
I had not reviewed Nordpool prices for a while, so I was quite surprised that my August bill is going to be 40% less than a usual summer month without adjustments. I believe that the difference will be even higher during the winter, when the geothermal pump kicks in and Nordpool prices vary more.
What I’m really excited about is that all this was done outside the power distribution racks, purely in software that lives some 50 kilometers away.