Just a caveat - the links are not “affiliate” links. I am just sharing what I’ve found in the hope it might be useful for someone else.
The first find is a low-cost wood stove that will work in a van or truck. (Lone Wolf 902 on YouTube demonstrates many of Pamoly’s line of small wood stoves on his channel. https://youtu.be/iu5DzVOV2JE. His reviews are thorough and he answers all questions that come in through comments.) These stoves, either titanium or stainless steel are designed for hot tent camping…so they come with chimney piping and the accessories necessary. I purchased a medium sized Dweller made by Pomoly (https://www.pomoly.com/) for $375.00. Of course, all the caveats apply. Be smart, follow the instructions and don’t be dead. I didn’t want diesel heat given the uncertain availability of fuels these days (I live in Europe…) and propane is expensive, availability is spotty and the canister connectors change from country to country. I also wanted a “dry” heat for the van. This stove is small enough that I can move it in and out of the van as necessary since we still don’t know what the status of gas heat will be this winter here - and I’d rather be prepared.
The second item is a great little rechargeable, cordless fan that works a charm and uses between 3-24w when plugged in with a DC motor.
The fan has three speeds, including an eco-mode that will run for 12 hours on one charge. It can be controlled via remote and the handle actually works as an LED light with two settings. It also has a wide swivel range to keep the entire room cool. The highest speed is too high for me - it’s not super inexpensive ($80.00 +/-?), but in these days of increasing heat - this might be a decent solution for someone that wants a low wattage fan to help stay cool.