Decades ago a friend of mine did a 2 stage water heating
system like this using his wood stove. A coil of pipe in the
stove percolated hot water through the first tank. The
second tank was used mostly for when the fire went out. It
isn't quite as simple as it seems though. The size of the
second tank is important. If it is too big it just acts like
a "cooling off" place and a lot of the energy is lost. If it
is too small it can't meet demand when the fire is out.
Today, with much better materials, especially insulation, it
probably wouldn't be nearly so hard.

Allen

> -----Original Message-----
> From: piclist-bounces@mit.edu [mailto:piclist-
> bounces@mit.edu] On Behalf Of cdb
> Sent: Friday, September 20, 2013 5:57 PM
> To: Microcontroller discussion list - Public.
> Subject: Re: [OT] Free Energy Hijacked from: "The Gift of
> Invention" - Designspark Mechanical 3D dwg software - Free
> as in beer
>=20
> I've just found an extract with links for the  Wisconsin
> University/NIST PV
> proposal, which is what page 41 of the magazine is
'lifted'
> from..
>=20
> http://sel.me.wisc.edu/trnsys/downloads/trnsedapps/dem
> os/pvsdhw.htm
>=20
> Colin
> --
> cdb, colin@btech-online.co.uk on 21/09/2013
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>=20
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