For Power: if you can and have the means you could also consider a so-called
Multifuel Generator that
"can be operated with diesel, heating oil, straight vegetable oil (rapeseed oil, canola oil, sunflower oil, coconut oil, copra oil, corn oil, soy bean oil, palm oil, jatropha oil, ...), cleaned waste vegetable oil or pyrolysis oil." When I looked into it a while ago, I found the following one quite interesting:
ATG MULTIFUEL 3SP Power Generator 3 kW | ATG and this one
Multifuel Biofuel Power Generator Diesel Biodiesel vegetable oil waste oil. The Multifuel idea for emergencies was something I researched a bit more extensively in the past, since there seem to be smaller type of devices that can do that you could actually carry.
Am I assuming correctly that we can't use old lard for the multi-fuel generator, because it's too dense, and the fuel should be more fluid like vegetable oil, even though this type of fuel clogs the filter at lower temperatures if I understood it correctly?
BTW, thank you so much for this thread.

It's really interesting, although I kept postponing these kind of decisions when it comes to energy! So, yesterday I finally took the bull by the horns and ordered a small infrared ceramic heater, but opted for
another brand, as the brand Cosmos linked to was only available second-hand. I also bought a small stove which runs on propane gas as well.
I also did some research into propane gas tanks and found a Dutch company that actually delivers these gas tanks to your door, which is very useful if you don't drive. You can even subscribe to having your tanks filled when they run empty. Again, it's useful if you don't live near a filling station, but then again I don't know how this company will fare with all the supply chain issues that are coming our way, although having these kind of connections could turn out beneficial!
Speaking of supply chain issues, I had a look at these multi-fuel generators and noticed that it will take the
larger ones three up to five months to arrive!!
Added: According to one of the reviewers of the small infrared ceramic heater it comes with a CO2 thingy, but I couldn't find that in the description.