I have heard that grease cars are not good in cold climates. Is that true. ? Then how cold?
To run a vehicle on straight fryer grease, the grease needs to be heated to the point where it’s viscosity is similar to that of diesel. To do this, most conversions use two tanks, one for regular diesel, and one for grease. The grease tank has a heat exchanger which takes hot engine coolant an pre-heats the grease until it’s thin enough to inject. This is around 160°F. Since one can’t drive on the grease until it’s hot enough, it’s not useful for short trips. Also, one must be careful to purge the fuel lines or grease before shutting the engine off. In cold climates, one would have to be extra careful, and the warm-up time would be that much longer.
This makes biodiesel which can be used in any diesel vehicle, the difference is between this and WVO which is waste vegetable oil, pure filtered but otherwise unadulterated cooking grease.
I believe either can be treated with a standard anti-gel additive but that does little to nothing as far as making the WVO more combustable, just keeps it a little more liquidey while heating.
Isn’t that preferable to having to juryrig tank heaters, modify the engine and whatnot? Also wouldn’t it be a more consistent fuel than just straight WVO?
It depends.
Biodiesel is more expensive, and takes a finicky chemical reaction to create. Running straight fryer grease is merely an engineering problem.