DISCLAIMER: I was referring to what I saw on the Chabad article(the first one linked to as "Yom Tov Laws") I am not considering at all Yom Kippur, I meant Yom Tov in terms of the idea of "work for food" is allowed for festivals.
I was wondering if driving an electric vehicle on Yom Tov would be allowed if the battery of the car is on from before Yom Tov and has a package to cook food filled with something that needs cooking placed on it before Yom Tov. I saw that you are allowed to cook on Yom Tov with an existing flame and enhance an existing flame. The way I see it, the batteries are being used from before Yom Tov are an existing flame and then driving would be enhancing the flame. I know this might be problematic with how it appears for other Jews, so if someone added a sign to the car saying that they were cooking food on the batteries, would it then be allowed? If the previous is allowed, how hot would the batteries have to be to be considered a flame, or is the fact of the electricity considered a flame by itself?