permaculture

["Lawrence F. London, Jr." <lflj@intrex.net>]

=http://lists.ifas.ufl.edu/cgi-bin/wa.exe?A2=ind0901&L=sanet-mg&T=0&O=D&P=50975
=SANET-MG Archives -- January 2009 (#72)
=Subject:        Re: Mini Methane digesters
=From:  Randy Cutler <[log in to unmask]>
=Reply-To:      Sustainable Agriculture Network Discussion Group <[log in to 
unmask]>, Randy Cutler <[log in to unmask]>
=Date:  Tue, 13 Jan 2009 15:49:44 -0600

=Would it be more efficient to extract heat from the ground by drawing air
=through a 4" tile line or by pumping water through a 1" pvc pipe?   It looks
=like a combination of digester, solar heat sinks and geothermal will be the
=optimum methods of heating. I also like the idea of placing heating pipe
=within the benches to heat the soil. I need to design a system that will
=incorporate all of these methods.

= R C

For the time being forget the hydronic heat source and go for direct gain via one or more solar closets; cheap and easy 
to build, very effective with mini8mal heat loss - can heat DHW with a heat exchanger also. This is old technology
(post 1988). Nick Pine has pioneered this concept and has built a number of 
working units.
The idea is to build a solar hot air collector (black copper plate in double glazed collector box) with hot air out and 
cold air return ducting to
a chamber/room, superinsulated, with lots of metal barrels filled with water inside. A whisper fan (12vDC solar powered 
for example) can deliver hot air to greenhouse as needed. A valve prevents backflow of hot air through the collector 
during the night.

I have a very old collection of files about this here:
The main collection:  
http://www.ibiblio.org/ecolandtech/alternative-energy/solar/Nick.Pine/
http://www.ibiblio.org/ecolandtech/alternative-energy/solar/
http://www.ibiblio.org/ecolandtech/alternative-energy/

And the Usenet newsgroups:

alt.solar.thermal
alt.energy.renewable
alt.solar
alt.energy.homepower

And here is today's Google search for:
"solar closet"
#
Solar Closets and Sunspaces
A "solar closet" is an insulated box filled with sealed containers of water, with a solar air heater attached to one 
insulated side. In a simplified solar ...
www.ece.vill.edu/~nick/solar/solar.html - 20k - Cached - Similar pages -
#
Live Webcam Passive Solar Closet Air collector
For the average home with R20 insulation, construct a solar storage closet with in the home using twenty 50 gallon drums 
of water. ...
www.zteck.com/passive/collector.htm - 25k - Cached - Similar pages -
#
Solar closet economics
House (c) is the same house as redesigned by a residential passive solar HVAC engineer, with a 4' wide x 16' long x 8' 
tall solar closet, behind some clear ...
www.ibiblio.org/london/renewable-energy/solar/Nick.Pine/msg00025.html - 9k - 
Cached - Similar pages -
#
Solar closets in a nutshell
A pound of water raised 1 degree F stores 1 Btu. o Solar closets can also heat water for houses, and serve as saunas or 
clothes-drying areas. ...
www.ibiblio.org/london/renewable-energy/solar/Nick.Pine/msg00026.html - 10k - 
Cached - Similar pages -
More results from www.ibiblio.org »
#
Article 13799 of alt.solar.thermal: Path: news.misty.com!not-for ...
Nov 7, 2002 ... Recall that Solar Closets (tm) live inside sunspaces. ... >Will a solar closet work have the capacity to 
provide adequate heat, ...
www.ece.villanova.edu/~nick/usenet/00001985 - 6k - Cached - Similar pages -