My lovely and talented wife made an off-hand comment on the playa suggesting that we bring dehydrated water next time. I had the thought that perhaps taking deoxygenated water would achieve the same end. Here’s my thoughts to that effect.

Methane (CH4) has a molecular mass of 16 amu and H2O is about 18 amu. Liquid CH4 is thus less dense than H2O. However, each molecule of CH4 can be exchanged for two molecules of H2O through the miracle of combustion.

Still, it would be a tremendous amount of methane, which requires a rediculously low temperature to remain liquid. My searching was able to uncover a few places that make LNG tanks for commercial vehicles. However, their insulation is only sufficient to keep the LNG liquid for about three days, which is insufficient for our needs.

Propane seems to be the best bet, although the C/H ratio is nearly half that of methane: it is widely available and liquifies at a reasonable pressure. The 0.5ppm of ethyl mercaptan seems to not be considered any sort of health risk, though it appears that SO2 is a combustion byproduct.