heating energy storage, renewable intermittant
lots of sand and lots of heat touted as an infill for intermittent renewables, not perhaps in the news like using hi tech electronics and flashing lights or sexy chemistry, but has the huge advantage of just working, and being easily and cheaply scaled to anywhere with space.
Reads to me like a twist on the old economy 7 idea, probably more use distributed near where heat is needed than as a battery at a power station.
Makes an alternative to oil tanks and propane tanks, though rather fewer joules per cubic metre, even at 1000C.
(a typical house propane tank is 1200 litres, or 600kg and each kg is ~ 50 megajoules)
(hot sand is 1.5 litres per kg and ~ 1kJ per kilo per degree about 1/4 that of water, but that boils.... )
so at 1000C about 1/50 the energy density of LPG.
Mike
