In addition to the engine heater, they may also have heating fans for the passenger compartment.
Northern cars aren’t equipped with sump heating but rather with something a bit more elaborate like this:
Things has certainly evolved over the 15 years that elapsed since I left Norway 
. I do remember the systems you mention but back then there was definitely an electrical heating element in the engine block which was predominant.
In addition to engine heating, you could also install heating fans within the passenger compartment so it would be nice and comfy before driving to work.
You get all that as an add-on for pretty much all cars, directly from the manufacturer (“park heating”). Some smaller diesel BMWs have it builtin because the engine may not produce enough heat to get the cabin warm (like our GA aircraft) but if you want to use it independent from the engine, you have to pay a four digit amount to unlock the functionality.
Who needs fuel? My e-Up when plugged in will also heat up the compartment. It was almost -20 here a month ago. No problem with the e-Up. In the morning the heater had done it’s job and the inside temperature was +21.5 All this heating and charging can be timed and remotely controlled, among a hole lot of other things, through VW car-net system (a remote system using mobile net). No problems with cold temps and electric motors
Electric cars are wonderful because when they burst into flames it certainly gets hot enough!
Almost all larger diesel cars and all 4×4s etc have a fuel burning heater, because modern diesel engines do not produce enough waste heat for efficient passenger compartment heating. The expensive option they sell is just the control unit that switches it on remotely.
Since the FBH heats the water in the cooling system it’s of limited use in traditional air cooled aero engine applications!
Here is an article by that Bush type about this topic:
Good post I had read his article a while back just couldnt remember where. It should answer most questions.
I still shake my head in wonder at the casual attitude towards per heat in Europe.
Piston GA operators owners don’t have a casual attitude with regards to preheat. However in comparison with the US they are a minuscule, almost inexistent percentage of airport users, so their voice (and needs & operational requirements) are seldom heard if indeed at all.
Shorrick Mk2, I have walked past the flight line at EDMA in the morning and see aircraft parked outside overnight with wing covers being removed etc. getting readied and firing up.
When I asked about it, I was told -2C is not that cold. For me anything below +3C is cold and requires a preheat. I think that article in AVWEB by Mike Bush backs me up.
