Comment by XorNot
6 months ago
Which they use all the time. If you did this at a district heating level, you'd just be running an electric district heating system, resistively, which you run all the time - it wouldn't be a dump load, it would just be the load and a very inefficient one at that (compared to a heat pump).
The point is all this stuff costs money to build, money to maintain, so if you don't use it most of the time the time you do needs to be incredibly valuable.
A 10kw heating element costs 250 euros, lets double that to make it able to switch off by the smart meter. Now if you used it 1% of the year and saved 5ct per kWh you would gain 43 eur a year. Not a super convincing ROI but compared to your 10kw peak solar array a very small investment. If you used it just 2% of the year it would already be pretty good and the switch might become very cheap in the future if most houses use load steering for all kinds of things