This is a really really clever idea.
http://www.cleantechconcepts.com/2016/01...energy-storage/
Desert sand, stored in an "hourglass" type arrangement, and dropped through a "venturi" at the focal point of a solar collector, heating it from 250C to 800C (or more).
Hot sand is stored, and used to shift heat into a process (could be any), and cooled (250C) sand returned to the top of the hourglass.
No pressure, no nasty molten salts, no environmental contamination if you leak some, and hot sand won't have convection currents to accelerate heat loss.
http://www.cleantechconcepts.com/2016/01...energy-storage/
Desert sand, stored in an "hourglass" type arrangement, and dropped through a "venturi" at the focal point of a solar collector, heating it from 250C to 800C (or more).
Hot sand is stored, and used to shift heat into a process (could be any), and cooled (250C) sand returned to the top of the hourglass.
No pressure, no nasty molten salts, no environmental contamination if you leak some, and hot sand won't have convection currents to accelerate heat loss.