Meow who would go and do that?
I mean, if you COULD run a car, or Defender, on cats I'd switch my engine over to a diesel right meow, but I just don't think with the technology available meow that it is possible.
On a serious note, there's a feedmill/processing facility in the midwest doing "cellulosic depolymerization" that's running the feedmill off the waste (i.e. left overs) from the processing plant. It's pretty cool, there's been a big push recently for waste to energy in my field.