I was at a tour of Skærbækværket many years ago, and as I remember it, when you produce power, you need to be able to control the voltage somehow. If there is a surplus of power and you cannot turn down production, you need to dump it or the voltage will go up, destroying electrical systems. One of the simplest ways to do this is to heat water, and when you have well established district heating it's almost a no brainer what to do.
It's a nobrainer, but the electric kettles are rather expensive and are usually therefore only bought to ensure production capacity in the case that the powerplant's own kettle malfunctions.
Besides, district heating produced on power from the grid is taxed as if produced on coal, as the power has no traceability. This makes it really expensive, unless you are directly hooked up to a solar or windfarm.
That's the law in Denmark at least.
PS: I worked in the administrative building just next door to Skærbækværket! :)
> district heating produced on power from the grid is taxed as if produced on coal, as the power has no traceability.
Sounds like there is room for improvement. E.g. an agreement with an energy provider and tracking when it was used on demand as a sink for excess energy instead of base-rate heating.
Ahh, it doesn't make much sense to install it away from a powerplant. It captures waste heat and electricity, where as one elsewhere would only be able to capture excess electricity.
