At Runway there was a giant steel bin that was always steaming from the inside. I took a glance inside once and saw a bunch of snow. Next to our galley sink was a sign saying DO NOT DRINK. Need water = melt sow. Downfall is that it takes a gas generator to produce heat to melt the snow, and cross contanimation occurs as it gets loaded into and sits inside the melt box. I think a solar water heating system (using the colour black as a catalyst for melt inside tubing or barrels) would work great in the summer.