"Brian Gaff \(Sofa\)" wrote:
I've often wondered why, given the ability of a vacuum flask to keep stuff
hot all day, why something similar is not used on storage heater insulation.
Even when you close the vents they are cold by the end of a day. So
electronic vents and a thermos around the bricks is what we need.

Probably rather difficult to make a 'jacket' that can be evacuated
without collapsing. A vacuum flask is (approximately) cylindrical so
the 'jacket' can support the vacuum (I'd guess the inner part is in
tension and the outer in compression without too many bending forces)

--
Chris Green
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