Russ Finch's project uses air tubes in the ground + solar exposure + earth sheltering for greenhouse heating. The websites and video offer some ideas.
https://greenhouseinthesnow.com/ https://www.youtube.com/watch?v=ZD_3_gsgsnk http://netnebraska.org/article/news/1007375/visit-nebraska-greenhouse-grows-lemons-and-oranges http://citrusinthesnow.com Note: additional considerations with regard to indoor air quality may be in order if planning to use buried air tubes to directly supply a home. Contamination and condensation of moisture inside the air tubes could lead to problems outside the tubes. I also do not know whether dust buildup in buried tubes is more or less of a problem compared to air ducts in a house. Cleaning could be a challenge. Hydronic systems nicely avoid these problems (but like most other design decisions come with different challenges, which in this case means requiring freeze protection). On Sun, Mar 21, 2021, 20:41 Robert Bruninga via EV <ev@lists.evdl.org> wrote: > For the digging cost please then consider using the ground only as a heat > source/sink for a heatpump. Trying to use the ground temperature at > existing value has such a low delta-T as to be useless compared to the > cost. Bob > > On Sun, Mar 21, 2021 at 6:48 PM BobK via EV <ev@lists.evdl.org> wrote: > > > Lee Hart, For my earth tubes I was thinking of at least 8 inches > diameter. > > I’ve not decided on the number of tubes. The end away from the house > would > > drain into a sump. The sump would be enough for a small sump pump that > > would get rid of the water. Any suggestion are welcome. > > > > Bobby Keeland > > Louisiana > > > > Sent from my iPhone 7 > > > > > On Mar 21, 2021, at 1:28 PM, Lee Hart via EV <ev@lists.evdl.org> > wrote: > > > > > > Robert Bruninga via EV wrote: > > >> The cheapest DIY ground-source heating is to hang an old Air > > >> Conditioner from the floor joists of a popular central room in the > house > > >> and cut a hole in the floor to connect the hot side of the AC to the > > room. > > >> The cold side remains in the basement air. A 10,000 BTU AC unit > > becomes a > > >> 20,000 BTu heatpump.... > > > > > > Even easier; I leave my furnace's air intake open in the basement in > the > > summer. The furnace blower pulls cooler air from the basement, runs it > > through the air conditioner, and it into the house. It has the additional > > benefit of reducing the humidity in the basement, where I'd otherwise > need > > a dehumidifier. > > > > > > Then, there is my grandpa's solution. He lived in the basement. :-) > > > > > > Lee > > > > > > -- > > > All children are born engineers. Watch them at play. They're not > > > just playing; they're experimenting, building and learning. That's > > > engineering! Then we get them in school and squash it out of them. > > > (Geoffrey Orsak, Southern Methodist University dean of engineering) > > > -- > > > Lee Hart, 814 8th Ave N, Sartell MN 56377, www.sunrise-ev.com > > > > > > -- > > > This email has been checked for viruses by Avast antivirus software. > > > https://www.avast.com/antivirus > > > > > > _______________________________________________ > > > Address messages to ev@lists.evdl.org > > > No other addresses in TO and CC fields > > > UNSUBSCRIBE: http://www.evdl.org/help/index.html#usub > > > ARCHIVE: http://www.evdl.org/archive/ > > > LIST INFO: http://lists.evdl.org/listinfo.cgi/ev-evdl.org > > _______________________________________________ > > Address messages to ev@lists.evdl.org > > No other addresses in TO and CC fields > > UNSUBSCRIBE: http://www.evdl.org/help/index.html#usub > > ARCHIVE: http://www.evdl.org/archive/ > > LIST INFO: http://lists.evdl.org/listinfo.cgi/ev-evdl.org > > > -------------- next part -------------- > An HTML attachment was scrubbed... > URL: < > http://lists.evdl.org/private.cgi/ev-evdl.org/attachments/20210321/5815b1c6/attachment.html > > > _______________________________________________ > Address messages to ev@lists.evdl.org > No other addresses in TO and CC fields > UNSUBSCRIBE: http://www.evdl.org/help/index.html#usub > ARCHIVE: http://www.evdl.org/archive/ > LIST INFO: http://lists.evdl.org/listinfo.cgi/ev-evdl.org > -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.evdl.org/private.cgi/ev-evdl.org/attachments/20210322/acc73292/attachment.html> _______________________________________________ Address messages to ev@lists.evdl.org No other addresses in TO and CC fields UNSUBSCRIBE: http://www.evdl.org/help/index.html#usub ARCHIVE: http://www.evdl.org/archive/ LIST INFO: http://lists.evdl.org/listinfo.cgi/ev-evdl.org
