This is a great discussion !
Wow - lots of very thoughtful information and discussion about how to make coffee while on-the-road. This is a perfect example of how valuable a forum like this can be.
After reading all your posts, for larger loads like a 1500 watt Keurig, it is clear that converting propane to electricity is far more efficient, safer, and cheaper than converting DC to AC.
When brewing on-the-road, a single-cup keurig (one cup water in, one cup coffee out) is probably a better choice than a larger Keurig that keeps water heated for multiple cups.
Great information and great discussion.