Initial rollout in a Roadtrek, but the propane fuel cell concept will gain momentum quickly elsewhere as a means to quietly, safely, and efficiently augment solar PV output.
Back in 1973 when I was in the Navy, we had a thermo generators that supplied power for some remote radio transmitters that used propane for fuel. The power out put was in the 12 or 24 volt DC range.
WATT fuel cell manufacturing headquarters is located less than 5 miles from my place here in Western PA. Lots of buzz over the company when they first moved in with the local media.