It is a good working fluid for waste heat power harvesting. (realclimate.org)
The collector label says it weighs 168 lbs - but that's dry, and this had working fluid in it, and rain soaked insulation. (builditsolar.com)
While a solar thermal power station of the type proposed by Aurora heats the molten salt working fluid only with direct sunshine, the solar PV will generate power in the diffuse light of cloudy days as well, ensuring an energy feed every day, not just on the sunny days. (ramblingsdc.net)