Poor Man's Geothermal

[@OutofAshesFarm]

UPDATE: Thanks for all the engagement on this video. As I said, good, measurable info is hard to find. As many of you have noted, what your seeing here is really still theory. We had one of the wettest winters in many years here in the PNW so I had to reprioritize, hence the lack of follow up. It will come eventually. In the meantime, check out our adorable piglets :) kzbin.info/www/bejne/anjUgJaIga2hd5I.

[@bigglesby12]

Great idea. Starting up a farm soon in the south and this will be GREAT for cooling. On a vaguely related note, what kind of panels did you use for the sides of your greenhouse and where did you source them Thanks!

[@OutofAshesFarm]

We used USA made Gallina Clear 8mm 2wall Polycarbonate. We had a wholesale source for this, which helped, as these panels are not cheap. I will do a video about the build in the nearish future.

[@bigglesby12]

Thats awesome. thanks!

[@TheKlink]

seems the quackulator wasn't quite lost, check this forum thread out; permies.com/t/37952/Subterranean-Heating-Cooling-System

[@awhodothey]

You don't need panels on the side (maybe hinged ones just at the top for ventilation). It's more efficient to cover the east and west sides in dark colored thermal mass and insulate the outside (all the way to the frost line, but not down to geothermal pipe depth)

[@Leeofthestorm]

It's been 4.5 years since this video. Do you have an update on the performance? What, by the way, is your square footage (area), and volume of this greenhouse? How deep are your pipes? Did you put aggregate around your pipes, or just backfill will the dug material? How thick are your walls? Are any walls insulated? Thanks for putting this out there. I like this idea.

[@violaspencer5628]

No replies…. Guess I won’t bother to ask my question - same as yours - how deep did he bury the pipes? Looks like the greenhouse floor was a few feet below ground level to start.

[@mikekinn4499]

He hated it 😂😂 heard it from his own mouth

[@nicholaslogan5185]

If ur still interested the calculator is back online being hosted by a different group. Since he got his calculations from there it should answer some of these questions I guess ✌️

[@groogleboogle]

Hi, I am from the UK and an old way of heating a green house before electricity was invented was to bury a hay bail and then dampen it and as it decays it generates heat. In your case however it would be easier to leave your dog in there as he seems quite happy rummaging around, DOG POWER!

[@casestyer1166]

Im thinking about raising meat rabbits in my greenhouse. Fertilizer and heat.

[@Eliukcory]

But they will eat every thing your growing. 👎🏼

[@casestyer1166]

Not if they're in gages ;)

[@groogleboogle]

@@casestyer1166 FREE THE BUNNY !!!

[@casestyer1166]

Ill free it... From its worldly body lol.

[@thomasg4324]

*EVEN POORER:* Place a large pile of compost on the outside of the greenhouse, and ram rebar through the wall into the compost. Chicken manure and leafs has worked great for me. Adding urine "turbocharges" the heat production. *If you place numerous rods of rebar 2 inches apart, they act like a radiator pushing heated air more efficiently without fans. But of course fans would aid in heat and moisture flow.*

[@mrbonus8423]

Do you know any videos where we can see this in action? Sounds cool.

[@stjimmy5294]

@@mrbonus8423 The youtube channel EdibleAcres has a lot of videos about heating greenhouses with compost

[@Rick-the-Swift]

I see Thomas following chickens around with a pooper scooper then peeing on the piles of chicken crap. It's an interesting image I now have stuck in my head😆

[@thomasg4324]

@@Rick-the-Swift I usually use my tractor bucket to scrape the chicken area topsoil, and coop shavings, into the compost pile....and I have been known to stop next to the pile from time to time and piss from the tractor instead of going to the restroom. Last week I taught my son how to write his name in piss from the front bucket of my tractor....although it was into a large snow pile. In November my neighbor said "good distance you have there" when I drove past her after pissing on the pile from my tractor.😎

[@russiannpcbot6408]

To make it even more efficient, setup a sterling engine run fan to spread the heat without using any electricity. Place the expansion intake by the rebar to use the heat from it. Have the condensing intake run through the wall to take advantage of the cold outside air. The high difference in temperature causes a piston to move back and forth. This can be used to rotate a fan without any electricity used. If the temperature gradient is high enough, you'll get a very fast spinning fan.

[@jimh712]

Very easy idea for moisture. 👍👍👍👍 The drain pipe makes sence for energy transfer, The ridges should cause turbulence... And the slits will let it drain... Thanks for figuring out my moisture problem. 😌

[@matteosmobilebicyclerepair5755]

Thnx for vid. Moisture into soil isn’t just to prevent mold, the evaporative cooling and condensing heat is also helpful I’m pretty sure, from what I have learned from verge permaculture and if I’m not mistaken they have a calculator you mentioned and also seem to be doing the first detailed study of the effectiveness of these designs

[@aion2177]

I would call it "Smart man's geotermal". Thanks :)

[@przybyla420]

Or truly sustainable, non-pipe dream geothermal.

[@duderino6171]

@@przybyla420 except it's a complete *PIPE* dream. You know, cause it's made of pipes? Right, right? 😆

[@buelowexcavating]

The formula I saw was one linear foot of 6" pipe for each square foot of building with 8' walls. Damp heavy soil will conduct heat better. I the 1960's this system was popular and performed well in many farm buildings. This is the first time I have seen this system used in a long time. I think the company installing it was called The Lords Power Company. The Romans used a ducting system made of stone, that would heat in the winter and cool in the summer.

[@Seriouslydave]

Same with middle east, they could chill foods with no moving parts only ducts.

[@phildurgin652]

Best way to remove the condensate from the tube would be to have a small sump pump at the end of the tube close to the house and don't use drain field lines with holes in it. Put it in a trap so the pump can be serviced when needed. Tilt the tubes at a slight angle so the condensate gravity feeds the sump pump. This will do several things: 1) the pipe remains sealed and no outside water can invade it due to flooding. 2) It keeps ground bugs from entering the pipe through the drain holes. Put a screen on the far end of the pipe that is outside to prevent critters and bugs from entering the pipe. Put air filter material at the outlet of the pipes so that mold and pollen are prevented from entering the home, or structure you are cooling/heating. Finally, put access traps into your pipe so you can run a tool similar to duct cleaning down the pipe......remember, these pipes are cool, moist and full of pollen, mold and dirt that is sucked into the pipes from outside.... You don't want to breath that air with all those contaminates in it.

[@leslietehaara7099]

Excellent practical advice, thank you sir.

[@consumelove]

Hey. I was wondering what the sf of your greenhouse is? Maybe I can just make one the same size as to use the 500 feet calculation. Thanks@!

[@jimh4167]

👍

[@1zebracrossing]

Here's a little tip it took somebody 4 years to develop this.He heats his house that is over 3,000 sq ft with valted ceilings when it hits 80°, the louvers open then the fan kicks in and exhausts the house back to room temp. I got to see this technology he's had it for 54 years now. They have regular glass windows about 18" wide two panes at 2" with a piece of mylar directly in the middle so when the sun rays come in they are trapped inside of the structure because they cannot leave they turn to heat rays and he has 7 plastic towers of water that absorb this heat and disperse it through the house. The house is turned so that it is untraditionally facing of the winter solstice the awnings or shades are meant to protect the house from this light heat source. I saw this technology several years ago the only time it didn't work one time in 24 years he said was when the fog came up so he had to revert to the conventional system as most people know it to heat his house for 24.00 bucks...... This is really cool stuff the house still had the conventional look. He has a really thick blue insulation. We had a short discussion of how air travels through glass and that's what led him to showing me his whole house how it worked...... Awesome is all I can say..... I would just like to develop a no fan system..... This will heat your whole house

[@cathrynmartin4395]

I come from the first copies of Mother Earth News back in the 1970s so I've seen a great deal of ways to heat/cool greenhouses. For winter, have you thought of taking plastic 55-gallon drums, painting them black, filling them with water where the sun will shine on them to create a great heat sink to keep the greenhouse warm in the evening? Or having a mass rocket stove where, similar to your 500 feet of piping, you direct a long set of stove pipes into a seating area that has mud or rocks to absorb the heat from the rocket stove which uses small amounts of wood. That's just a couple of heating ideas for winter. Summer shade mesh for the windows will allow the light to get in but help reduce some of the summer heat - that and if you are older like me, back before homes had air conditioning, houses had a large attic fan (and I grew up in Oklahoma so I guarantee you, I KNOW about summer heat). The attic fan was turned on early, before the sun came up and pushed the coolest air into the house, then turned off until later...when the day's heat was too much, the attic fan blades were reversed to exhaust the hot air from the house. That's what you do...pull in cool, blow out hot with a good sized fan. Works!

[@1SpiritualTruth]

Thank you. How deep are the drainage pipes?

[@just-dl]

Great point about using drainage pipe. My plans are now adjusted!!!

[@Ahomesteadersdream]

So you’re a few years into this greenhouse, how’s it working out?

[@MrCharlesEldredge]

I went into a public bathroom on the interstate in Florida long ago and they had a pyramid shaped roof with venting at the top, 2' x 3' concrete block sections turned on their sides near the floor to allow air in, and two industrial wall fans up on the walls to create a cyclone effect. it drew air in thru the openings near the floor and vented it out the vent at the top. It actually did make it pretty cool in there. I've thought of copying that for a large concrete shed I have, but instead of just openings near the ground to let air in.... installing several perforated drain tubing runs underground...which would bring much cooler air in. It would be extremely passive and simple system system that would cool pretty good I think. The runs would start above ground with a U-shape pointing down with screening to keep bugs and insects out. Any thoughts anyone?

[@joycebowen8958]

Check out earth tubes. It's exactly what you are describing.

[@Ihaveausernametoo]

Awesome! Thank you for this. Started digging after I saw this, it's getting there (I'm in southern Sweden). Happy growing!

[@markj6442]

solar heaters, the can setup encased with your ground batteries piped into the bottom manifold trough should heat and pull your lower colder air, you will probably need more than one solar heater

[@ZeddZeeee]

awesome! this makes the concept of geothermal heating more clear! very useful for off grid living!

[@aw8079]

Put your dog on a treadmill! Power forever.

[@garlicdawg]

good info...thnx for sharing....how big is your greenhouse.....is it sq ft or cubic feet...?

[@islandersx]

What will really help is to have a temperature differential switch. if your objective is to store heat, with temperature differential switch the fan will deactivate when ever the air temperature inside green house is cooler than pipes underground.

[@BlackjackArmyCaptain]

Thank you for your knowledge, my. Friend.

[@royhoco5748]

I have small green house 10 x 12 that I plan to enlarge to 12 x 24. I plan to use geothermal heating and cooling plus solar panels for electricity. My plan includes three 4 x 4 x 4 compost bins along the back wall with a window over the first bin and 3rd to load fresh material from the outside aged mature compost out the 3 rd window. the setup will allow me to work the compost year round indoors and when it is ready to use it will be right where I can get to it easy. I also plan to make a small conveyor belt system to move compost from one bin to the next to save on work with a pitch fork or shovel. the conveyor will be portable to move from bin to bin or even outside to move new material through the window to the first bin or out the 3rd bin window right into my club car golf cart with a dump bed.. There will also be a water faucet inside see I am getting older and I need to find ways to make my labor easier.

[@mermanofthesea5667]

Very interesting! I have watched several videos on this type of system gathering information for a future project. You are the only one that addressed the issue of condensation underground and moisture issues. I understand the idea that condensation can be removed by exiting the drainage style pipe underground. My question is what keeps ground water from entering the drainage pipe during a rainy season. I am thinking OR can have lots of rain and therefore the ground water can build up. Just guessing OR may have a sandy or rocky soil? Here in NC, we have lots of rain and a high water table in my area. Maybe all the gravel surrounding the drainage pipe would allow the condensation to leave but I have no experience if ground water could actually build up enough to come back in? Any experience with this?

[@mariourbieta5705]

At that depth it won t be an issue

[@jimh712]

You could run even lower drainage pipes to a sump so if there were a problem it could be pumped off... Unless your green house is on high ground... Then it could just be drained off

[@markj6442]

everything should be build with a good weeping system, proper vertical and horizontal weepers all tied together like with any structure should be more that sufficient.

[@northpolltv6598]

Your dog bumbling around in the background is hilarious!

[@jsmythib]

"he's looking for something!" lol

[@cheffsolo7739]

Short video , but great can't wait to see a longer video , and how you doing on this project.

[@therespectedlex9794]

When you say 500 feet, how far down underground is it? How far down do you go, and how do you do that?

[@brenttanner9889]

I’m not an expert in this at all, but I believe you just need go down like 4-6 feet or so, maybe a bit more. Then you snake the hose for 500 feet, or as long as is needed for your application. Essentially you are just turning the ground and your hose into the coils on your cars radiator. As the air gets sucked in and out of the vents he showed it goes a few feet underground and snakes through the pipe long enough for it to change temp to match the geothermal temp.

[@therespectedlex9794]

@@brenttanner9889 Thanks, that's a lot clearer to me now.

[@murraynelson696]

@@brenttanner9889 I'm not sure where exactly he is and am also no expert. I would expect that you would want those lines deep enough to be below the frost line. I am looking into options that would be able to work for me, I would probably have to go much deeper being in the Canadian parries.

[@botchvinik8668]

@@murraynelson696 6 feet is deep enough to get the year round constant of 50 - 55 F. Even in Canada that can work, PROVIDED a) the buried hose is beneath the greenhouse and not outside it's foot print (wall parameters), and b) the interior air in the greenhouse isn't allowed to go below freezing temp. during winter. In this way there isn't any frost to be driven down when one enters and walks about in the greenhouse.

[@Stevenhufnagel]

Put an other layer of plastic lining on the inside to achieve a double wall with air gap in between for insulation.

[@MorganBrown]

nice video and nice implementation. Most people who do the horizontal "earth tubes" seem to trench outside the footprint of the greenhouse. You were smart to stay under your greenhouse! I have a vertical earth tube for my much smaller experimental greenhouse. So far so good (when it's below freezing outside, it's above freezing in my greenhouse), but I will do some more rigorous measurements throughout the winter.

[@JohnGuest45]

Trenching outside can be useful in hot climates where cooling is more important than heating. The unprotected mass loses heat to the surrounding ground and the sky at night which increases the cooling capacity for the following day. You can do the same with a sheltered system by rerouting the inlet/outlet at night to draw outside air through the tubing and exhaust it outside the greenhouse.

[@KaleidoscopeJunkie]

Great looking greenhouse ! The calculation is .1 linear feet of 4 inch tube per 1 cubic ft of area to be treated. Example - - A 20'x25' SF foot print with 10' ceilings equals 5,000 SF. Multiplied by .1 equals 500 linear feet of 4 inch tubing. My notes are from the late 90's and unfortunately I did not record calculations for larger pipes. It seems to me that larger pipes allow too much air through and it doesn't have enough time to change temps. Larger pipes or shorter lengths need slower air flow.

[@awhodothey]

KaleidoscopeJunkie No it isn't. That calculation is a myth. The correct calculation is entirely dependent on the rate at which a given diameter of pipe, spaced at a given distance, placed at a given ground temperature, can dissipate heat into a soil of a given thermal conductivity, at a given air pressure.

[@jayhayward7579]

Depends on how exact you want to get @GreatMooseDetective. You forget to include relative humidities, air speed, temperature difference between soil/air and inside/outside air, DLI, etc. But how exact do you want to get before the time spent creating an algorithm for all these variable creates a diminishing return on money? That calculation that KaleifoscopeJunkie provided is a pretty good rule of thumb for the amount of tubing needed. The MOST important consideration is to have the capacity to do at least of 5 air exchanges per hour for heating and up to 20 air exchanges per hour for cooling. Otherwise, getting into the semantics of all the variables is an exercise of ego.

[@nonyabidness7207]

Yes, but once they finished typing up their comment, they were feeling really good about finally being able to spew some high school math theory!

[@iivanov22]

What if we pump water in the pipes then use an old radiator from truck with a fan? Ithink we will need less pipes for sure.

[@sskfrey]

KaleidoscopeJunkie what ist that in the metric system?

[@stringventure]

Thanks for this info. I wish that calculator was still available. How large is your green house that you needed 500ft though? Knowing that would help me get a gauge for how to figure that.

[@MarksTLC]

Agreed! I’m guessing your pipe is below your areas frost line.

[@markj6442]

pipe the collector barrel/trough to a manifold like pipe that connects to a solar heater and use that or multiple ones to draw the air up from your battery with solar powered fans....also if you made a stone and cob pit with a centralized RMH, you could also use the ignited RMH as the way to draw up from your earth battery freely...I used a trough because it was easier to pipe on multiple solar heater can setups on a narrower lateral south facing stud type surface vs a round barrel where only one side could face south at one time.

[@sawoodboy]

In the winter how will the water get out of the buried drain pipe? How deep do you have to bury the pipe to achieve the constant 50 degree temperature year round? With all the corrugation and bends in the pipe how does that affect the efficiency of the fan?

[@OutofAshesFarm]

The water seeps into and is absorbed by the soil. It's not enough water to be an issue. As far as the bends, corrugation and fan efficiency, I really couldn't say. The bigger issue there would be leaks or plugs in the system keeping air from moving freely. But, I don't have a control. I imagine it would be more efficient if the runs were totally straight, and if you have enough space, that's the best way to do it, but I can't imagine it's a big enough issue to really matter. It really should be below the frost line, but the deeper you go the more consistent the temp. If you are in very cold or very hot temperatures, you would go deeper (maybe 4-8 feet) and in more moderate temps 2-4. Some of our pipes are a bit deeper than others. Ideally, I would have gone further down, but that wasn't practical.

[@JohnGuest45]

Constant ground temperature only applies to ground that is open to the elements and influenced by those elements. A piece of ground covered/sheltered from the elements by a greenhouse that has heat added or removed from it will have an annual temperature based on the new energy in / energy out balance. Over the past 7 years the ground beneath my greenhouse now averages 5 deg C warmer than the soil outside at the same depth, which hasnt changed.

[@OutofAshesFarm]

JohnGuest45 thanks John, really appreciate your input here. I figured that the ground d temperature would increase over time, especially since my tubes are pretty shallow. Do you think the same would be true in a system where the tubes were, say, 5' under. I've seen them that deep in other systems, especially where temperates get much colder.

[@JohnGuest45]

It could just as easily decrease if the new energy balance is negative, this would be likely where heating is dominent and the summer gains are low. A finite mass will hold a finite amount of energy and, contrary to popular belief, it`s not recharged by heat from the earths core :) Most of the systems out there dont monitor enough parameters to get a picture of what is happening, some dont have any sensors in the mass, which is where you need them the most. Duct inlet and outlet temperatures are meaningless without a flowrate. A large in/out temperature difference may appear impressive but if it only equates to a teaspoon of warm air every 5 minutes, its not going to do much to heat the greenhouse. The same applies to cooling. The important parameters to monitor are the mass temperature at various depths and locations in the system, airflow rate, duct in/out temperature and RH. External mass temperature measurement using multiple sensors and depths allows you to track and compare the temperature of the ground outside.

[@redcloud870]

Two questions.. How deep did you bury the drain pipe...and is the drain pipe you used have weep holes to allow the condensation to seep back into the soil?

[@TribalLady12]

How cold does it get there in winter? How warm in the summer? What is the depth the drain pipe is buried? Thank you!!

[@TheTammyable]

Watched this 3x. Yours seems simpler. Gives me hope. Love the barrel intake and outtake.

[@mattthomson1689]

Ya, love the barrels, drain pipe, fans (low voltage solar?) and future shaded thermostat. Been considering insulating my house foundation wall, since it has a decent working height, with a winter temperature of 45, summer 55. And that’s a ventilated area. Also considering a small green house at some point in time. So many projects.....enjoy you day!

[@jackpalmer5067]

The dog is wonderful and great information

[@edwardbenton8323]

I dig down 2 feet preferably on a slope high side North low side South so you can easily enter the door on the South end. Placing concrete blocks 3 rows high on all sides and 1 row high at the doorway. Allows the heat from the ground to avoid frost in the winter. Build up dirt on the outside of the blocks to retain heat, wet soil is one-third better than dry.

[@solfeinberg437]

It's looking nice. Post updates. Where is the pipe running. By drain pipe, you mean it's perforated so water can go into the ground? Versus like inclined and running to an exit?

[@squashit339]

Omg the dog 😂😂😂 at first I thought the noise was coming from my room and had me looking around.

[@GARRY3754]

Made me curious if excavating 42” to frost line would create a heat in flow? Your greenhouse made think of one over excavated area. Insulation surrounding perimeter....

[@jowoo7237]

Dementions of greenhouse? Thanks I have a passive solar as well and I'm trying to find a way to keep the heat steady. Cold is less of an issue then hot.

[@just-dl]

Hey, it looks like your space is roughly 16x24, possibly averagevroof height of 9’. Serious guessing here. This is close to 3500 cubic feet, which makes a rough piping ratio of 7:1, volume to pipe-length. If my SWAG is close, 280-300 cfm fan power would work, which is wonderfully reasonable. How’s my math look? Did I get even close?

[@rymichael7203]

Simple ratio of old to new size

[@algreen266]

Hi so basically you are in a closed shell and you are pumping the air inside the shell with no windows open during summer . So the air is pumped into a 600 feet hoses under the ground , where the air is cooled and comes out cold to lets say 70 degrees is that correct?? If that is the case how can we calculate regarding the area and how many hoses we can put in the ground.Thanks

[@jerryglen986]

This has been general knowledge around KZbin for years. Thanks for education people😁👍

[@mattthomson1689]

True; geothermal is quite a viable solution. I’m glad to have this explanation of humidity having a likely moisturizing influence with soils near the drainpipe collectors.👁

[@marianocelentano2864]

What is the depth of the pipes where they are buried and what is the size of your greenhouse? That would help us to know, Many thanks for the info.

[@johnmcook1]

BELOW THE FROST LINE I WOULD GUESS DOUBLE THE DEPTH OF THE FORST LINE AT LEAST.

[@lindajonesartist]

Ecosystems Design found a copy of the Climate Battery calculator talked about in this video in some web archive somewhere and made it available online here: www.ecosystems-design.com/climate-battery-calculator.html (Note: It's an Excel spreadsheet file, so you'll need to have access to Microsoft Excel to be able to use the file.)

[@PAC56]

My security software reports this website as a threat...

[@Greenwashedhipppie]

We are building a walipini currently. I may do this next winter depending on how the Walipini works.

[@scottpalmer1616]

I watched a video online that said to take the cubic feet of the greenhouse and divide it by 10 and that will be the length of underground drain pipe to lay. If you want to have all of it under you greenhouse so the ground can also benefit from the heat exchange, then go down 8 feet and the foot print of your greenhouse and lay some and put 18 inches of dirt and fold it and lay it again, repeat until you have the correct length. He also put 4 inch styro foam along the walls before filling in all the way up the 8 feet.

[@OutofAshesFarm]

Yeah, that's significantly more intense than what I did, but probably a great idea.

[@JohnGuest45]

If you use that formula you wont have enough tubing and the excavation cost will be silly expensive. Consider a 10 x 12 x 8ft box, thats 960 cubic feet divided by 10 gives 96ft of tube. Excavating 960 cubic feet of ground to install 96ft of tubing is plain crazy. The idea of folding the tube is also daft because for one, you cant bend 4" ads tubing to that radius, and two, the losses in a 96ft length of tube will be silly high. You might be able to run 50cfm through it which means it`ll take a little over 19 minutes to put the greenhouse air volume (960ft3) through it, thats just 3x per hour. You need to put the entire greenhouse air volume underground at least 10-20x per hour (more is better). Your tube simply cant support that amount of airflow.

[@kwlweapons]

What I saw a youtuber do LDSprepper was dig a trench 8 feet deep, insulated on the sides and possibly bottom and then layers of tubing spaced out and fastened onto a chicken wire mesh and then droped into the trench and then packed with soil, repeat 3-4 times in layers. John what your saying is he would need more tubing and a larger fan to be able to circulate enough air?

[@JohnGuest45]

Hi Shrive LDSPreppers install isnt based on anything technical, more wild ass guess and hope it works.. He used 4 extremely long lengths of 4" ads tubing in a serpentine layout on a single level. Its very hard to purposefully design a layout that is less efficient ;) Installing a larger fan wont help if the tubing cant support the higher flowrate. Take 10 drinking straws, join them together end to end and see how much air you can blow through them. Now take 10 more straws and form them into a tight bunch and see how easy it is to blow through them. Both arrangements have an equal amount of tube, surface area, cost etc but one wotks and the other doesnt. It worries me that some folks may blindly copy these fatally flawed designs. Burying the tubing is a one shot deal, believe me its a lot of work and you wouldnt want to do it twice because it was wtong the first time ;) LDS uses 4x 180ft of ads tubing, if you run 50cfm through each you`ll need a fan capable of providing 200cfm at (at least) 0.7" wc. LDS`s greenhouse is 7200 cubic feet and 200cfm will put all the greenhouse air through the tubing 1.6x per hour (assuming no mixed air). Thats just not going to cut it ;) So, lets try a bigger fan that will put 250cfm through each tube, which puts all the greenhouse air through the tubing 8.3x an hour. Finding a fan capable of 1000cfm at 17" wc will be an issue ;)

[@kwlweapons]

Hey John thanks for the reply, You make valid points and provide good food for thought. What are some other design considerations you would advise be taken into account other than bunching up the tubing instead of lenghtening it? What would happen if you had a long, length wise, greenhouse or structure? From what I understand you don't have to cover the whole length of the greenhouse to benefit from the thermal battery effect, i.e you can dig a trench in the middle and burry all the tubing maybe in a hexagonal pattern or similar to maximize area utilization and then run the blower through that. I'm also wondering if it would be necessary to join all the bunched up tube into one main line or seperate them into 2 main lines to get more even airflow distribution from the blower. I appreciate your time and input! Cheers

[@806rambo]

Super! What's the fan power?

[@trinitytwo14992]

Can you show how you put the drain in, and also how you intend to cultivate within the structure? Are you doing raised beds? What are you planting? Thanks, k

[@timothykenyon106]

Hi this is Tim and I would like to know the cubic feet of your greenhouse, and the diameter of the duct pipe

[@franslaimbock6185]

Pipe was 8 inches

[@friendlyneighborhoodmechan2606]

Nice info thanks .are THE tubes in the ground how many feet?

[@MrPittsSox]

you could also add black barrels of water on the north wall

[@shellyangell100]

Thank you for the clear concise information!

[@jimh4167]

How many cubic feet is the green house Along with your 500 feet of pipe Will help calculations of different size green houses

[@casestyer1166]

Ive heard that you need 1 foot of 6 inch pipe per square foot (on a 8 foot ceiling) what is your cubic feet in your greenhouse?

[@Adam-uo2mc]

Contractor here. The dimensions of those plastic panels are 4 feet by 8 feet , so if you count the number of panels 4 panel's (16 feet) wide by 8 panels (32 feet) long. So 16' X 32' = 512 SQ FT, looks looks like one foot of drain pipe for every square foot

[@demil3618]

How deep do you need to go to get. temperature of 50°? That‘s almost sauna level, pretty good but I guess it needs to go deep down for that. And how many sqm does the greenhouse have?

[@keigan9006]

Very cool and I love that idea of the poor man's geothermal. If you can pull 20 degrees of heat out of the ambient heat of the soil at a depth of 4 or 5 feet beneath the green house - then you are able to go far in keeping the air temps in the green house abouve freezing - even on the coldest days. Question - did you place thermal barriers around the out side of the green house in order to stop the incursion of frost under the edges of the green house? if that were to happen, I would imagine it would have some significant effect on the amount of heat transfer you could harvest.

[@pfrost6745]

Is there a book you can reccommend? My husband is a contractor, we want to do this PRONTO and our planning now and building soon. Would love more info...

[@ruthlongridge]

Brilliant! What are the dimensions of your greenhouse? It would help us do the calculations off the basis of 500ft of pipes.

[@dereksimenac8844]

should look at compost heat, the CO2 from the compost helps the plants breath

[@coleweede1953]

Doesn't that smell bad in a closed system

[@nickway_]

@@coleweede1953 compost wont smell if you have your Nitrogen:Carbon ratio right. If it smells add more carbon.

[@Thomas-rx9ur]

How deep are your drain pipes? In general soil temp is constant year round at about 6’. It doesn’t look like you have your pipes that deep. That depth will affect the benefit. As proof of concept one of my professors developed a similar system to provide AC to a campus building. He used a secondary coolant system to take full advantage of the rankine cycle to remove latent heat of vaporization. Also had to drill a lot deeper than you have.

[@441rider]

I have maybe the smallest geothermal greenhouse at 39 sq/ft and 8 foot tall and get 55f out from a 5 foot hole with chamber buried under reflective foam cap and 4 feet or more of dirt. It is mostly for cool air the ground is very porous.

[@zachz1018]

Now run your drain pipe into a 30 ft chimney, with wind scoop at the top. You can capitalize on atmospheric pressure too

[@iainsime2614]

Hi have you got any updates of your greenhouse it sounds great

[@jasonvue1985]

when you say 500ft how deep are going with that 500 and how big is your house? this the first i've heard of this method very interesting. i'm in the process of build a green house and looking for a type to build.

[@FreeSCV]

I saw a nebraska guy growing oranges in -30 winters saying 8 feet down for his....that's only 1 source but it's something...

[@frankenz66]

The temperature 6 feet down is supposed to be at the same temperature as your annual average air at that particular locale. That's about 57-58F degrees here by me.

[@pierrenormandeau5414]

What is the surface or the dimensions of the green House please ?

[@TheTammyable]

I would so love an update on all your temps in your greenhouse. Or Is update out there and I’m too 🤓 to find it?

[@lilyhawk111]

Since you are circulating air collected from underground, you also need to consider Radon. You need to know if radon is a significant issue in your area; what the parent bedrock is. Granite and shale can generate more but even limestone can in some areas off gas Radon. R adon is a heavier gas and more of a problem in basements than above grade living space normally; also it degrades in 3.5 days but the volume of air changes per day that the conditioned space is subjected to could be a problem. Research should be done at a higher level than this project.

[@Follower_of_The_Word]

If you insulate your greenhouse it will make it much more effecient. All you need is add a layer of clear plastic on the inside and install a small solar-powered fan to blow air between the walls to keep it "inflated."

[@commonconservative7551]

roger s ....it would be quite the trick to add a second layer of plastic to the INSIDE of a greenhouse and it would look tacky and cause all kinds of trouble

[@HarmonyHillHomestead1]

commonconservative whobcares what it looks like if it works......

[@commonconservative7551]

lady farmer....have you actually imagined how you would hang a second layer of plastic on the inside of a green house?.......not duck tape i hope

[@reidcrosby6941]

He purchased the better double layered rigid plastic, which accomplishes the same thing as double layered plastic (flexible) Would another layer help? Sure, but he has already created the same/similar capacity of insulation as the double " inflated" plastic. R

[@lyndonpatton331]

Double sheet plastic and a fan is actually a very common tactic. google is your friend

[@ColtonRDean]

I think that tubing is one cubic foot per one foot length. So if you used 500 ft of tubing, you have 500 cubic feet of tubing. Divide the area of the green house by the area of tubing, there’s your formula.

[@thatsonebadhatharry8610]

Why in the world would you think a 4" or even a 6" tube 12" long would equal 1 cubic foot. A cube 1' X 1' X 1' equals 1 cubic foot. 4 6" circles will fit in a 12" X 12" Square with spaces in the corners and middle of the circles. So you can't just multiply the length and expect to get the correct answer without having the correct formula. The area of a 6" circle is 28.26 sq.in. so it would take a little more than five 1 ft. Sections of tubing to equal 1 cm. 500ft. Would equal about 100cf. So the volume of a cylinder or tubing would be pie times radius Squared times length.

[@ColtonRDean]

@@thatsonebadhatharry8610 I wasn't there to measure it myself. I estimated the radius and calculated off the top of my head as 6", when more likely the diameter is 6". With a 12" diameter tube, one cubic foot would be about 15". Not bad for an estimation, but more accurate when I actually use pen and paper. 12" diameter = 6" radius. (6 x 6) pi = 113.097 12" x 12" x 12" = 1728" or 1 cubic foot 1728 / 113.097 = 15.278"

[@thatsonebadhatharry8610]

@@ColtonRDean Yeah I can see that happening. Just looking at the video it looked like 4 to 6 in. tubing so that's what I thought you were going by. I guess we were really on the same page after all.

[@preppingforlife264]

Great video I wanna build something similar, I never see where the air intake is and how that should be done! Could you do a video of that and exactly how those pipes run

[@stuartwakefield1657]

Hi, how deep are the pipes under the floor?

[@TheGreatTimSheridan]

It would be nice to be able to freeze the earth under the greenhouse in the winter. Interested to hear what kind of fan controller he will use. You need the battery temperature, the outside temperature and inside temperature in order to capture all the modes. It should be indoor range, with a series of gates trigger the fans, or to shut off the fans, and a failure mode, when the fans aren't helping and the temperature is out of spec. That's to prevent you from running the fan unnecessarily.

[@mikeysgametime8914]

5 years later what would u do different? Change?

[@abalcome]

Hey great video, not a lot of information out there on this. Just a couple questions on the setup: How many Cu.Ft. is your greenhouse? How long are your pipe runs? How many CFM is that fan? Thanks!

[@OutofAshesFarm]

The greenhouse is roughly 6,300 cbf. It's a very irregular shape because it's attached to the shop but set at a southern solar angle, so difficult to get it exact. The fan is an 8in Hurricane with 745 cbf. That will move the air around a little more than 5 times per hour. I prefer a bit more to a bit less. The pipe runs are variable. You can see a pic of what it looked like in the ground before it was covered if you go here: www.outofashesfarm.com/blog/2016/10/9/poor-mans-geothermal

[@JohnGuest45]

The issue with variable pipe lengths and bends is they unbalance the system so some tubes will get more air than others. This isnt a big problem if you check the airflow rate through each tube using a cheap windspeed meter and re-balance the system by restricting (squishing) one end of the faster flowing tubes. This will provide more flow in the slower tubes. It can be a tedius job as it usually takes a few iterations to get the flowrate equal in all the tubes but its well worth the effort in the long run. Having all the tubes in a relatively single layer is not ideal as it increases the tube to mass ratio (ie more tube/less mass per unit area). Ideally, the tubing should be evenly distributed throughout the entire mass both horizontally and vertically.

[@brianwhelan92]

JohnGuest45. I sure do love your comments i wish you would help me on desiding what my lay out should be on a 17ft diamiter dome (230sf floor ) and 12ft tall (total volum 2120cf) would it be better to go out side my dome a liltle bit seeing as its not sqare or to stay inside it? Im trying to be one of the few to desine something that is done right turning total volum 40to60 times a hr i live in Kentucky and iv been growing orange and lemon trees for 6 years inside now im wanting to put them in ground all year plz help me john guest 45 [e-mail]

[@kutectar]

Great i am thinking the same Can i implement it in home. Same system

[@PsychNurse.]

500 feet of drain pipe. What's your greenhouse dimensions? Thanks in advance.

[@theoriginalkeepercreek]

I appreciated your video - so much so that I subscribed because I wanted to see your green house project progress. Went to your home page...No video(s) following this one up. What happened?

[@OutofAshesFarm]

keepercreek Winter! well be back with more soon. thanks for subscribing :)

[@MrGaZZaDaG]

@@OutofAshesFarm i can't find these videos my friend

[@Kognito72]

Can you please convert you temps to Celsius?. We don't know what you're on about

[@Soothsayer210]

I am in Canada, can this be used here in our Sub Zero temps. Also how much was your investments? I am just trying to compare it with a Geo thermal closed loop Heat Exchange system.

[@NorthernLycanthrope]

Is that perforated drain pipe? I'm guessing so...

[@MrGaZZaDaG]

wheres the rest of the videos bro?

[@msamour]

Hi, what climate zone was this system designed for? Would it work in -20 areas?

[@franslaimbock6185]

Any climate zone where you can get under the frostline.

[@albertravn]

Would be great to see more info on this system, perhaps in a more visual way, like a graphic representation? Awesome video anyway, thanks!

[@justgivemethetruth]

I thought you were going to say you heated your greenhouse with a compost pile, which is what that wooden containment t structure behind you looked like to me. Would that work? Also, a simple diagram on paper of what your did would be helpful to understanding it.

[@carlroberts7830]

better still when installing septic system use a 2000 gallon tank with 8 inch cavity on all sides enclosed with water lines snakeing along the walls to use for heat in winter and build your green house over the septic field

[@buelowexcavating]

In our area septic tanks freeze. If the tank had insulation over it, the warm air in the summer might make it work here. For insulation, we put 4' of dirt over the tank. If you don't have dirt you could substitute 1" of high-density foam board for each foot of dirt. Make sure it has good grass cover, that is good insulation.

[@un-limited7009]

Did I miss the part about how deep to bury the drain pipes? 🤔

[@Horse237]

8 feet. 54 degrees. Warm enough for soil biology but too cool for worms.

[@kieranhanrahan2883]

@@Horse237 8 feet? I am luck to have 8 inches of soil!

[@Horse237]

@@kieranhanrahan2883 Texas is having problems because they are not prepared for the kind of winters Michigan has. Talk to contractors around the country and ask them how deep to bury water pipws so they don't freeze. There were men trying to get away with burying water pipes 6 inches in the Deep South. No More. We entered a Grand Solar Minimum just like the Maunder Minimum of 1645 to 1715 when weather was so bad that wheat prices spiked up to 400% in some years. I was talking about dirt and not soil. That is where to bury the pipes taking 54 degree air to your greenhouse year round. Cooling in summer and in winter it takes less energy to get the air from 54 to 70 degrees than from 18 or 20.

[@briholt100]

@horse237 Like what was just said it depends on your location. In the northwest the freezing depth is only 12 inches. So do me I may only need to go down 2 feet But that is because our temp is heavily moderated by the ocean. But upper Minnesota for example you'll have to go much deeper. Locals will know.

[@Horse237]

@@briholt100 My point about 8 feet is that we just entered a Grand Solar Minimum just like the Maunder Minimum of 1645 to 1715. It was much cooler back then. The price of wheat in the UK spiked up to 400% in certain years. In 1709 there was a Big Freeze in Europe and the top 40 inches of the ground in France froze spiking food prices 600%. So obviously if we are entering another Grand Solar Minimum as evidenced by last summer's historic floods in China and the most recent polar vortex wreaking havoc as far south as Texas and Mexico, we ought to dig pipes deeper than what contractors did in the past. That is why if I ever get a place, I will dig my geothermal vents 8 feet deep. And I will install lightning rods to protect my animals. We will be getting a lot more cloud cover, more rain, more hail, more snow and lightning. I have read of several farmers in Europe losing 50 sheep at a time to lightning strikes. And I have read of several snow storms in Saudi Arabia. Edward Maunder was the first to notice the reduction in sunspots and cooler temperatures. Dr Valentina Zharakova was one of the first to notice the reduction in the Sun's magnetism during a Grand Solar Minimum. This allows more Cosmic rays (nuclear particles from distant stars) to enter the earth's atmosphere causing more clouds, rain, hail and snow and striking the surface of the earth and energizing volcanoes and earthquakes. The Big Freeze back in 1709 was caused by 3 volcanoes erupting in Europe which blocked their sunshine. People who have read diaries of Americans and Canadians might be familiar with the bad weather of the period. And the most famous record of bad weather was that of the Lewis and Clark expedition of 1803 to 1806 which was during the Dalton Grand Solar Minimum. The Dalton Minimum was when the New Madrid quakes (4 quakes from 1811 to 1812) shook the area from Memphis to St Louis even reversing the flow of the Mississippi river. Of course there also was a New Madrid quake back in the Maunder Minimum on Christmas Day in 1699 but hardly any white people were in the area to record the destruction. We need to prepare for future events by buying lightning rods to protect our animals and digging 8 feet deep for our geothermal greenhouses. There is Good News. No Chinese government in the past 2,000 years has ever survived a Grand Solar Minimum at least according David Dubyne of Adapt 2030. There is Bad News. Joe Biden has reversed the previous President's Executive Order so China can participate in our electrical power grid. Not a good idea. If any of the 1.4 billion Chinese people riot because they cannot find food, then we will have to export our food to them which will cause Nationwide Food Riots in America.

[@jeffbrown7246]

Is that drain pipe coming out of the ground and into the barrel? What type of drain pipe is that?

[@shawnr771]

what is the interior cubic volume o f your green house? diameter of the drain pipe you are using?

[@LTWGH918918]

I’m having trouble getting my low grade geothermal system to work. I have 5 sets of pipes with a length of 80’ each and I had a small amount of air on with a 250 cfm inline vortex fan on one pipe but almost nothing using a 500 cfm inline vortex fan. I’m not sure why it isn’t working. The pipes are free of water. Any thoughts would be appreciated, thanks Ed from Lundy’s Farm Market.

[@1framistan]

Heat rises in air and in the soil. If you installed the pipes UNDER the greenhouse, then you defeat the purpose of it. The 60 degree warmth would rise up out of the ground anyway! If you try to COOL the greenhouse, and you pump warm air in summer UNDER the greenhouse..... then once again the warmth will rise right back up and INTO the greenhouse! Therefore, the pipes must be buried AWAY from the greenhouse. I did extensive experiments on this subject and wrote an eBook about it which is available at LULU.com at this link: www.LULU.com/spotlight/davidmundy and it is the book titled, "Home heating and cooling experiments"

[@vincentcarlson2715]

How deep underground are the pipes?

[@lancemcque1459]

Do you have an update video on this Geothermal system?

[@nathanvee6135]

Stellar work man.

[@James-vn2vf]

How deep do you need for Thermal Mass and do I need a maximum outside film for all season production Colorado, USA Thanks, Jim

[@ateleskier7066]

Two projects in progress: 1) Greenhouse geothermal. 2) Dog on a mission to find that thing he misplaced. I want to see more of #2.

[@kallakrastev769]

hi, this is nice, you can put a nilon from the inside of the policarbon on the same frame for better isolation, and less fan starts

[@michaelbahr7267]

how far down did you bury the pipe? and where do you live> Minnesota might have to be deeper

[@Badboyifier]

(Noob question) Where do you have the fans? Isnt it supposed to get the outer air into the greenhouse?