Solar Boosted Geothermal Heating for a Greenhouse

[@SimpleTek]

This concept is the best design I know of for long term heating a solar greenhouse! Love to hear your thoughts!

[@l0I0I0I0]

One thought is the warmer it is, the closer you get to the 1:5 efficiency's. Point is if the ground is a lot warmer, heat pump may be as efficient as 1/5 the electricity and will only turn on if needed meaning if the ground is hot enough, it uses 0 electricity, if you set it up and design it that way. It gets closer to energy storage with the capability to heat for really cold days as well. It can even cool with dual imput setups.

[@l0I0I0I0]

Lastly, the volumetric capacity of water is crazy higher than sand. If you are already going to insulate, just build a pond and increase the heat capacity 5-10 fold. As long as you don't heat it beyond 90-95c, it's perfectly safe.

[@SimpleTek]

@@l0I0I0I0 this is obviously why large concentrated solar plants use salt not water!

[@l0I0I0I0]

@@SimpleTek Yes once you pass the 95C, it's no longer simple. 😂

[@davefroman4700]

You need an apron of insulation around the heated area but yeah this will work just fine. You do need some sort of an expansion tank/drain back for this system though or it will break pipes.The tube collectors will provide heat even in -30C on a cloudy day.

[@FullCircleTravis]

My house has two windows on the south wall that are 6' high by 10' wide each. In the winter at -25 on a sunny day, it will be 25°C with no heat on. Building design is a huge part of efficiency.

[@SimpleTek]

Absolutely

[@drzavahercegbosnaponosna5974]

@@SimpleTek can you heat an existing heat multi-residential building with 21 flats? Does it have to be radiant heating (ceiling, floor)? each flat in the building has gas heating boilers and radiators at the moment.

[@SimpleTek]

@@drzavahercegbosnaponosna5974 much more details needed

[@Austin1990]

Love the idea! I need to run some heat transfer simulations to investigate how something like this would work. I don’t have a pin expensive CAD program capable of running such a simulation, but I am in the process of whipping a 2-D simulation in Excel. I love the idea of being able to expand the solar collection area of your greenhouse to include the tube arrays. A significant limitation on passive greenhouse heating is the raw amount of energy that hits the greenhouse. Something else on my mind is how to remove heat quickly enough from the greenhouse during summer to capture the heat rather than simply venting it out. If you are heating the ground, the ground may be too warm to cool off air even in summer, but thermal simulations may answer some questions.

[@SimpleTek]

@@Austin1990 great response. I believe in fans for quick cooling, but I live in manitoba where we don’t get big heat in the summer

[@masterdebater8757]

Forget about the foamcrete or any crete for the "Ground Battery" dig your battery hole 8-10 feet deep put down perimeter of IFC blocks 2 high add to the floor 4-6inches of Expanded Polystyrene (EPS) foam board. Now it gets interesting with this part. We are going pack dirt into those ICF blocks use of rebar is optional. Line the inside of that battery with a pool/pond liner or some strong plastic maybe the fibered canvas stuff for greenhouses is like 10mil with fiber. This plastic does a few things for us 1 unlike when doing under slab insulation we are not worried about it filling with water later we would prefer to have it fill with water for better thermal exchange. But we dont want that EPS to float up so the plastic will hold it down as we add mass. Now lets add 1-2 feet of fill and tamp/pack it down this should be done in 6inch lifts but we dont want to hurt that foam so do a 1 foot lift then another foot. Next fill the walls up with the dirt packing to the frost line and fill the wall in lifts of 6 inches and tamping it the best you can. Now back to the battery at this point we are still at a depth of 5-7feet and we lay the entire floor with our hot line from solar the loop over loop method or concentric method using less total length of pipe is your choice. Those long metal staples for holding shade cloth can be your friends to help hold the pipe in place. Now we add another foot to the battery and also the outside of the wall up to the point the inside is filled again limit the range of lifts and compact the soil we dont want anything shifting the wall around to much. Now we lay our pump side line 1 foot above the hot line. At this point we can get our liner put down the outside of wall and do another foot lift. We will then continue until the battery is full to the frost line leaving outside of the wall 1 foot shorter and we will cap this battery with another layer of high quality plastic and down the outside of wall adding the last foot around the wall to trap plastic again. Dont worry about it being water tight as i said we need that water if it wants to come do work let it. Last we have to backfill the site with soil if you prefer source some top soil if your soil is of low quality and add 6 inches of top soil to finish. Now you have your "ground battery" it is time to design how you will use it. If it was me i would source not only solar pool heater panels but also like the content creator mentions a small PV array directly feeding 2 of those pumps. Solar DC to run the pumps and go not only under the soil or floor of green house but also to some 55gallon drums lining the north and east since i am in a northern climate. These barrels would be plumbed in the top of first one then out the first just 6 inches from the to top towards the second barrel in the chain into that barrel 6 inches from the top and a drop pipe to the bottom then repeat 6inches from the top out to third then 90 to the bottom rinse and repeat for all barrels. You can use a horse troth auto waterer or a toilet float valve or manually keep up with the water levels. The last barrel in the chain is return to the ground battery from the bottom of that barrel which will be your over head reservoir for your ground battery. I would temp control pumps coupled in all 3 ways barrel, floor, and radiator using the AC i would bring to the green house and contactor switches or set up deep cycle battery/ies and attempt using car relays and the available solar DC/DC. My one exception would be the fan on the radiator a common house fan is not appropriate for this use. I would rather source a squirrel cage unit from a furnace or other source forcing through the radiator using AC power from the grid and avoid the costs of batteries and hassles dealing with invertors and all that jazz. There are other option for the fan you could build a frame and use a fan with a shroud sucking through the radiator. Either way you suck or blow you need to pick the cold off the floor and blow it clear to the other end of green house preferably blowing from west to east or north to south depending on your orientation. No mater how you slice it the pump for the radiator and its fan are both needing more energy than im willing to pay for solar and battery to deal with. It is so much cheaper and more reliable to power them off the grid and displace the energy later with Solar grid tied with some micro invertors. One should have redundancies in the system so i dont think the AC power is optional if your looking at any issues for that radiator or solar to fail or just not produce a few days in a row. Those redundancies not only include the ability to increase solar heat, solar pv to a size to work but also a back up way to charge the battery, heat, and there comes the old school methods of yesteryear and that is to burn wood either inside the green house or outside of it to produce hot air from a controlled air space around the stove but to also be able to wrap that stove with copper and plumb it back to the heat line of the "ground battery"... You got 2 legs so everything you do should have 2 or more legs just the way nature intended it. Dont make your greenhouse hobble while you get to walk around freely. If you think displacing the AC grid power with solar it to expensive think about doing a ground mount but with a wooden pergola with rafters on 2 foot centers angled near 25-35degrees due south depending on where you live for me it is 34 degrees angle 10degrees off of south towards east. Then cover the pergola with uni-strut bolt panels to that with standard hardware from under side to the panel frame not through middle with fancy expensive hardware. Add some 350watt panels and enphase iq7a micro invertors per panel and enphase combiner. Dont cheap out on micros the ones that do 2-4 panels and cost 50dollars less are not your friend they are for solar fields and low wattage panels. You do need Qcables but, you can cheap out and use standard AC house with or THHN and standard boxes instead of there home run wires and expensive male/female adapters for your end of string run to the combiner box. You will save in many ways doing this you wont need the power for greenhouse except winter time, you got a new pergola to hang out under cheaper than any solar mount set up, you dont have to roof it, the enphase micros rarely die and if they do only that panel goes out. If you had a big honking invertor and it dies= no power and 3-8K gone. You dont need batteries saves enough for college right there. The system breaks even in 5 years since that is about when your big honking invertor would have broken and icing on the cake the micro invertors last easy 25years and since they make ac power you can run normal old AC wire back to the main panel you dont need all these little bits and bobs all the solar people try and sell and if you can build a greenhouse i put my money on it you can build a GREEN Pergola too. Mines 24x24 (actual 28x28feet counting angle and over hanging panels) from 16feet up my 2 story right to the ground looks like a A-frame house roof i got the bigger micros and bigger panels but that set up get you 900kwh/month easy under 20K for the entire pergola and solar if you do the work. Im now looking at my next move either mini split or point of use water heating its a close call since only 2 of us here im leaning towards the minsplit so i dont have to tote as much wood and she is leaning towards hot water thinking it will effect her shower in some meaning full way but it wont.. The windmill heat generator looks awesome but seem like a busy system to get right for me in the north here. Guess i will be stuck feeding the 700lb cast iron monster wood (ass-warmer 3000) stove in winter. Good luck to anyone that managed to read that far i hope your head is a full of ideas as mine is and your hands are capable to do at least one of those ideas.

[@SimpleTek]

thank you for the HUGE reply!

[@dumbsathanass8669]

hell yeah brother 🤙

[@Max-eb4pu]

I think this is the longest reply ever on KZbin lol. 'Guinness World Record"

[@sz4179]

Thank you a million! Please write a book, I'll buy it. Trying to figure out how to capture these ideas as you know cant copy comments. Screenshots galore? Thanks again!

[@priestesslucy]

_My eyes are burning up_

[@growingtolive2383]

I think it would be awesome if you went more into detail what every element involved is. This will help all of us beginners.

[@SimpleTek]

sounds complicated

[@Davidmc23]

@@SimpleTek it is complicated isn't it? I was left wondering if you actually built what you are talking about. The lack of detail, pics of your setup, objective results aka data and a few other things make me wonder....you are the one monetizing the topic, a snarky "it's complicated" isn't much of a response to a legit comment.

[@SimpleTek]

@@Davidmc23 tricks is for kids, do you enforce that too?

[@Davidmc23]

@@SimpleTek I don't get your cultural reference. Tricks is slang for Johns which is slang for guy paying for you know what....what do kids have to do with it? I'm on the west coast, we are different here. Anyways I get that internet people drive you crazy however it is the business you are in and your just snarky for snarkys sake. Perhaps take the time you spend asking us to support you to reset your vargus nerve or something to calm and center yourself.

[@SimpleTek]

@@Davidmc23 people who think they are smart usually aren’t

[@bruceleonard81]

I truly like this idea alot. The people who talk it down want money from you. Great video thank ya man.

[@SimpleTek]

Thank you for the kind words!

[@pete1853]

I like this idea. I have been thinking about an even smaller version for my very small greenhouse. Homemade solar collector and a couple 55 gallon barrels buried under the 10 foot by 12 foot greenhouse. It would be for season extension by moderating night temps here in Colorado. I know it wouldn't get me through winter, but it ahould help extend the growing season some.

[@SimpleTek]

maybe upgrade to ibc totes from 55 gallon drums and you'll get deeper into the season!!!!!

[@firefox39693]

Ground-source heat pumps really are better for the climate here in Canada. Air-source heat pumps are great. But once they reach their limit, then their backup heating element has to kick in to provide the process heat for it to do its thing. The idea of having a solar thermal assist is even better. It pumps more heat into the ground. Solar thermal systems can be paired with ground-source heat pumps on the same circuit. Literally, all your home heating, hot water, and the heat for your greenhouse, or pool (if you have want) can come from zero-carbon solar and ground-source heat.

[@SimpleTek]

I have a video on air heat pumps geothermal assisted too

[@siov4279]

I love digging!! I dug 6 foot hole one time through shale a d clay for 35 feet once... EVERYTHING ELSE GAS BEEN EASY SINCE!

[@SimpleTek]

That’s awesome

[@MrSpock-sm3dd]

dig dig diggin in the sun. Schosholoza!

[@gailemberson7759]

I am in the Westport, Ontario, Canada area. I started designing a lean-to greenhouse on the end of my house. It will be an, 18' long, 16' wide and about 14' high, arch. East west orientation. I won't get into the details of the build itself, however, the heating system is what I wish to discuss. But first some land details. I call my 2 acres, Bedrock Flats. Most everywhere here the max you can dig down is anywhere from 1" to 8" before you hit bedrock, in some areas it is on the surface. However, my house has a crawl space of about 40", the foundation walls sit on the bedrock, which brings the main level up to about 4' above bedrock. All the ground around the house is back-filled up close to the main level. So where I am putting the greenhouse has about 36" of back-fill. My thoughts are to dig out the entire area, where greenhouse will sit, down to the bedrock. Place a cinder block wall, anchored to the bedrock, insulated with 2" rigid insulation on both sides and flaked out around the three exterior edges with 4' x 8' of 2 " rigid sheets (to help prevent frost from getting into the area). Here is where it gets into the heating system. With this small of an area, will laying 1/2 pex water lines, coiled as you suggest in one of your videos, back-filled to grade, and run up to a circulating pump to push heated water in summer down into the earth battery and reversed in winter. You can see where I am going with this. The question I have is - will this relatively small area, foot print, be enough to gather heat in summer and store for winter. I want to add something here that I find interesting. I have small 16 x 24' shop which sits about 30' from my house. I ran a water line out to it which sits on the bedrock in about 8" of soil, insulated and heat traced. However, I find that the heat trace very seldom comes on. I am thinking that it has something to do with the bedrock. It goes down quite deep, 20 to 40 feet in places, I know because of the well drilling in the area. Is this in itself some kind of natural earth battery? Will this help with my greenhouse heating system. Will the system even work at all? Thanks Mike

[@SimpleTek]

Good questions. One possible solution is to use a well instead of digging for heat, but that depends on your ground water temperature. You can make an above ground insulated earth battery too

[@gailemberson7759]

@@SimpleTek Yes a water well would work, running it through a water to air heat pimp, but this would be expensive. I don't want expensive - lol. I have a cold climate heat pump for my house and plan to run a supply and return duct into it which will help heat it. The solar earth battery, if it will work, is only to help with the process. I plan to start shortly so that I am ready for spring. I will let you know the results.

[@SimpleTek]

@@gailemberson7759 please keep me updated!!!

[@marthaadams4393]

Glad I found you again. YT unsubbed me from a bunch of my channels and I finally found you again -good to see you.

[@SimpleTek]

glad to have you back!

[@marthaadams4393]

@@SimpleTek I have told lots of people trying to figure out how to get a greenhouse up in Appalachia (weather swings are huge here) Any new bldg going up here (not soon) will have your geothermal heating system put in.

[@SimpleTek]

@@marthaadams4393 that’s awesome

[@marthaadams4393]

@@SimpleTek just wish I had know years ago and all of my buildings would have it.

[@EastBayFlipper]

This is genius. 😊 The only modifications I would make would be: Think a full foundation with foam insulation around sides and under the floor. Use insulation and lots of sand, feet of sand and have them staged 60cm apart so the lowest layer, 60cm above the floor is solar, then a secondary heat supply like a rocket stove heater and coils circulating antifreeze proof to high heat is another 60cm above solar, in the center of the battery. The top layer is the collection coil and delivery to the greenhouse or whatever then capped with refractory wool and a concrete floor for the greenhouse or garage. The poured walls of the battery, like a basement but only for thermal storage Use all metal high temperature materials because this will get unrealistically hot and will require the use of the solar panels as hear radiators for excess . An air gap under the floor would allow for access through the refractory wool for repairs but would need weeks of cooling and full breathing masks for PPE and start digging after remote sensing the target issue. You can also use vertical wind turbines to generate power and use the dump resistors in the heat battery 🔋 This would comfortably heat a home and greenhouse 😮 I've been looking for backup power for heat and this would be the perfect supplement for a heat pump with a controler that activates the battery circulation circuit to the house for economical operating and guaranteed heat😊

[@mrosengren4130]

Been looking at passive solar greenhouses, might also put this in with it for winter heating. Every little bit helps!

[@SimpleTek]

Cheers

[@roberttomsiii3728]

Just some things to consider and need further research as well as testing in my opinion. My most significant concern with an aircrete project has been the potential for it to become waterlogged. In my parts we have a 6-ft water table and a relative humidity constantly above 65%. As I understand it solid concrete has a insulation value similar to adobe. ( R values are simplistic way of measuring insulate value however keeping it in common reference values, about R1 per foot. I've seen home tests that show aircrete having a potential r-value as high as R6 per inch ) As the concrete begins to soak up the humidity and groundwater depending on where it's placed the r-value goes down. I acknowledge that aircrete by definition has has bubbles of air in it and that increases the r value but also makes the concrete more permeable and as such fluids move through it more easily. As a middle ground the consideration for me has been styocrete, basically taking trash styrofoam then breaking it down to beads and blending that into the concrete slurry so that the concrete is acting more as a binding agent, although this still has the potential issue of a significant portion of those beads not being closed cell.

[@SimpleTek]

Aircrete doesn’t get waterlogged

[@roberttomsiii3728]

@@SimpleTek Can you direct me towards some information that shows what is changing to make the cement no longer water permeable?

[@jimw125]

Paint the aircrete with shower waterproofing membrane like Laticrete or Red Guard

[@sherryallen3650]

I think that the styrocretev

[@sherryallen3650]

Whoops. I think that the styrocrete adds to the r value and is easier to get to a proper density and consistency. As well as making it light by area and cheaper. It sounds like a great idea to me. Again I am a total novice.

[@Robert-zs3do]

You need to insulate under your heating source and on all sides because the ground pulls the heat down, Solution builds an underground pond smaller than the greenhouse, Use Pond Plastic on the bottom and sides of the hole / then insulate the bottom and sides of the hole / then Use Pond Plastic on the bottom and sides of the hole. Build a Greenhouse over the Pond to completely cover the Pond. heat your underground pond during the daytime and use that to heat the greenhouse at night.

[@SimpleTek]

Sweet

[@williamwalter8554]

Hi Scott, I hope all is well, and you are now editing all the video you captured this past summer. Cheers, Bill

[@SimpleTek]

I am!!!

[@rw-xf4cb]

Curtis Stone and a few others been talking about sand batteries. Theyre looking at concrete tank or large diameter pipe and insulate the outside of it fill with sand then run tubing in and out of it. This is another option if you dont want to dig up the yard (though smaller system though can get the sand up to hundreds of degrees). Curtis was looking at it as a dump load for his solar so he can heat his home once the sun goes down.

[@SimpleTek]

Curtis is wonderful at solving problems like this without considering ROI

[@l0I0I0I0]

Hey great idea! It gives me some ideas. If you line the geothermal dig site with cheap space blanket, tape it tight, fill with sand, and cover with more space blanket, it will hold more heat. Down side, you can't use it for geo cooling needed in the south.

[@l0I0I0I0]

Not sure how long space blanket will last???

[@SimpleTek]

Great idea! but aircrete is probably cheaper and better insulation - being waterproof and long term lasting

[@l0I0I0I0]

@@SimpleTek yes it's the difference between cheap and triple cheap. Huge supply of Space blankets are like less than US $50. I would consider both. What would you mix into your cement for insulation?

[@SimpleTek]

@@l0I0I0I0 dish detergent soap suds. Ends up like styrofoam

[@l0I0I0I0]

@@SimpleTek I may hit you up when I'm ready to try that. Perlite is really cheap, perhaps a mixture of the two for strength. I'll make some graphene 1% to strengthen the concrete 30% or so.

[@larryw.7311]

I love it. Planning on something similar later this year, great video.

[@SimpleTek]

Awesome! Thank you!

[@serdarakdurak5332]

congratulations you are a very good analytic engineer and also very didactic and convincing

[@SimpleTek]

Thank you for the kind words

[@riversedgegoatdairy297]

Another great video. Makes me think more and more what I should do with my 'wallipini' green house build for 2022. What am I thinking? Straw bale walls. 3 to 4 feet dug into the ground. Air exchange thru a solar battery. Secondary solar battery using the principles in this video..... To assure that my average winter night time temps are maintained for citrus trees :) Look fwd to the next video! "Simple and cheap" solutions!!!

[@SimpleTek]

Thank you for the kind words!

[@riversedgegoatdairy297]

@@SimpleTek now you have me thinking. How can I keep a thermo mass of water or glycol in 1000 litre totes say at 80 degrees Ceslisus??? Wondering how much insulation I would need? Hmmmmmmm...... Wrapping the totes in straw? And 4" insulation then burried? Non pressurized loop into the green house...... Will it be enough to keep a green house 15+ degrees Celsius all winter?

[@SimpleTek]

@@riversedgegoatdairy297 clay acts as a thermal mass too around the water containers

[@codysaunders7348]

I will be incorporating this into my greenhouse design, thank you!!

[@SimpleTek]

Sounds great! Thank you for the kind words!

[@frankschultz4509]

Hey mate thanks for the inspiration. I recently buried a 1000l tote tank in my greenhouse for a battery, and plan on making two 4x8' solar water heaters out of pex pipe to feed it. This will hopefully heat this 700sqf greenhouse with insulated infloor, and possibly a cabin beside. What do you think?

[@SimpleTek]

That is awesome! you might need another tank for the cabin unless it doesn't get that cold there!

[@frankschultz4509]

@@SimpleTek I'm on Vancouver island, rather mild climate. I'll let you know how it goes mate!

[@SimpleTek]

@@frankschultz4509 as it's -30' here today, I'm jealous!!!

[@dismayedtrinket2518]

​@@frankschultz4509- turn it into a biodigester and you can make nutrient rich water, heat, and fuel that you could burn to heat the greenhouse (as long as you are very careful). You would lose out on compost though.

[@themovingintosleepmethod]

Thanks, great info! I've started to look for sustainable greenhouse

[@SimpleTek]

Glad it was helpful!

[@gerretw]

How about a dual system? Bury the pex about 4 - 5' down under the green house connected to the solar hot water heaters to warm the soil like a radiant heated floor in a house. Install a second layer above it to capture the heat in winter. Then bury a field of pipes outside the green house, to use for cooling. In the summer the water heats the soil while the other field cools the GH. when winter arrives, the cooling system is shut down except on warm days, and the upper layer of pipes extract heat from the earth battery?

[@SimpleTek]

Interesting

[@GRINGO_CTM]

hello, all good? just checking missing your content! Hola from Spain.

[@SimpleTek]

Thank you! Just been busy with the RV park. More content coming!

[@brianweishahn9131]

There is a geothermal greenhouse in Western Nebraska that you may want to see! They grow amazing things!

[@SimpleTek]

you mean Russ? He does great work but this is a boosted version of his greenhouse for people living further north without the same ground temperatures he gets

[@thomaskuchaski6235]

Starting the spring early we're going to be building two greenhouses in Taos New Mexico based on this principle scientifically it works out great we will be giving an update when we start and videos etc on KZbin this is going to be fun

[@SimpleTek]

That’s awesome! Looking forward to the update

[@paulwittmer6838]

I like this system concept. A concern with keeping aircrete dry is realistic and similar to otner comments. Applying a coating to the aircrete might be considered. Another possibiltiy is making a small hill above the ground water line and placing the "heat battery" inside the hill.

[@WhisperingWildMarketFarm]

I appreciate you sharing your research and Ideas. We are just a bit south of you 2 miles off the coast of Lake Superior on the US side so loads of wind. I was a bit surprised to not see a water tank and an a wind mill as part of this video. Capturing the winter wind and turning it into heat is very appealing. Anyway thank you for anther interesting video.

[@SimpleTek]

Thank you for the comment! Check my archives, there is a video on using a windmill to heat a greenhouse in there!

[@davidbuck1614]

Make large rows of compost and add to it threwout winter, u can raise worms on compost which helps plants as well, but you'll get some passive heat from compost, add black barrels of water as your resevors that heat up in the sunlight n release it overnight. Run water pipes thre compost piles to heat water inside, run ur plants on heated hydroponics threw the winter. If u have birds or fish u can feed birds on compost and raise bug farms to feed them n fish. Gives ur birds a sunny and warmer place to winter. Helps with feathers n egg production. If ur greenhouse basment was a pool for raising fish you could place a geothermal unit underneath it during construction. If it's basement depth you'll get the geothermal effect plus a large resevor for fish raising. And can stock ponds with what u raise over winter.

[@SimpleTek]

Ok

[@bonesyncro]

Really really cool, so how do I calculate the amount of ground space required per 100sqft of greenhouse or M2? I have multiple 800sqft hoops, we were looking into a boiler system, which would also regulate irrigation water temps as well. The quote was about 60K, crazy expensive. Propane unit heaters are about 15K plus propane lines and tanks and gas. This seems like the most efficient over long term as well. Thank you for the video, been loving your info you put out!

[@SimpleTek]

At this point I’m just guessing, lots of factors like soil type, insulation, climate etc to consider. Better to go bigger than not enough.

[@MikeKeesler]

Rocket mass heaters are about the best supplement for the money. you can burn anything in them, from twigs to pellets, to algae oil/briquets. algae after all is the food/fuel of the future. ;)

[@csandlund1]

@simpletek any leads on how to do the calculations? I've got a small space (~200 sqft) and am thinking about going down further to get the volume.

[@bryanbock7]

This pipe manifold system is a good idea. Try combining these four Ideas. A sealed steel piping (melting Temperature of 2300 F) manifold a kilometer long or more with 25 percent of the manifold set flat above ground and the remainder below ground placed at the bottom of a compacted sand pit. Vanta Black or Super black heat paint to coat the above-ground portion of the steel pipe. Two custom-built Tesla valves that are mounted at each end of the piping manifold are set for input at one end and output at the other end, the higher the diodicity (number of restricting segments) the better. and finally the sand (melting Temperature of 2900 F) for the storage of the heat. The transfer fluid could be Air (capable of obtaining 1000F or more), water (boiling temperature of 212 F), or oil, (Depending on the oil used. Standard auto oil is about 525F). The Tesla restrictors in the closed pipe system cause the flow of material in only one direction based on the difference in temperature. The pipe material transfers heat to the sand for temperature storage. Extraction of the stored temperature can be accomplished with a passive or active system. Unfortunately, drawings can not be placed in youtube comments. Hope this gives food for thought to your excellent ideas.

[@SimpleTek]

If you go too long with the underground pipe you don’t get any additional gain

[@skylerstevens8887]

@@SimpleTek wouldn't increasing the pumping speed bring back that lost cooling rate though?

[@SimpleTek]

@@skylerstevens8887 I’d think slower pump speed would transfer more energy?

[@chrisdavidson8525]

I have just discovered your videos and I am so glad I did! They are a treasure trove of ideas...I am sure I am going to have a LOT of questions going forward 🤣 Thank you so much for all of this!

[@SimpleTek]

Thank you

[@stephenpahl7538]

1970's Popular Science Story - Solar under greenhouse heat battery, stores above ground solar heat collected in large insulated pipe crossed sections of dug up , piped and refilled soil (soil temps above 200F stored) temps 60 to 120F available with about 4 months heat in -20 temps

[@SimpleTek]

that's awesome, but still just a climate battery. this is a level up

[@bogdan8r]

The most durable underground insulation is foamed glass. Additionally, the heat transfer coefficient is practically independent of the moisture content.

[@SimpleTek]

Cost

[@AubreyZhang]

I see one critical issue, that is, your greenhouse has one layer of covering which will not give you the needed insulation to keep the thermal energy collected. There is a better way, the SolaRoof way. Our idea is to turn the single layer covering to double layers. When it is hot in summer, we spray water inside to cool it down and store the solar thermal energy in water; when it is cold in winter, we fill the cavity with bubbles to prevent the thermal energy from leaking out. Once you combine solar and geo thermal this way, it opens up the whole thing and gets away from many other issues with the Liquid Solar system. Note that soap bubble foam is MIDDLE state between liquid and air. We can call it Bubble Air Solar/Geo Thermal solution.

[@SimpleTek]

Sounds complicated

[@AubreyZhang]

@@SimpleTek Not at all. Using your geo thermal term, the soap reservior is simply your heat sink. In fact, the geo thermal works because of massive amount of water in the ground. You know it, the level of water table determines where is the constant temperature zone in the ground.

[@grant2531]

What about putting the battery under the greenhouse and allowing it to radiate up through the soil you are growing in? Also put the heat collector in the greenhouse as well, to try and lower daytime temperatures and raise nighttime temperatures?

[@SimpleTek]

It works but you sacrifice regulating the temperature as you can’t control how much heat radiates up

[@royglixon]

Any paper writeups or example plans? Ideas are great. Some ideas about implementation even better. Thanks!

[@SimpleTek]

@@royglixon cheers

[@lunatik9696]

everything is relative. My off grid cabin only had a small generator at 1st. I got the small Westinghouse quiet model. I added solar panels and a small battery. I still had to run the generator all night. Gas generators are initially the most convenient, but least cheap option for making power over time. I was producing more power from panels than I could store so I upgraded to a bigger battery. After that, the generator only has to run every 2-3 days or so to charge up batteries to >= 80%. As I increased my power generation, I also increased my power usage. At 1st, it was just lights and a computer. I used propane for heat. Propane produces a lot of condensation. The 1st Summer the generator ran the A/C directly. (not good for generator) The 2cd Summer, the generator only charges the battery. I now have a microwave and minifridge, upgraded A/C to dual inverter and new this year a small electric heater. I am in process of adding more panels and another big battery to, hopefully, almost never having to run generator. I considered geo thermal during COVID 19, but couldn't get any one to dig the trenches. I will again have excess power, but that will be used to charge my (PH)EV next year. I may revisit geo-thermal next year as I expand more. It is a continual process of learning and implementing.

[@SimpleTek]

Thank you for the story

[@TheRebelmanone]

Polar Night Energy is a company using sand battery technology too. It has a plant with 100tons of sand is producing heating for the city of Kankaanpää in Western Finland. That is just another example of a working model to tell them about when they try to tell you it can't be done. HINT: you can't have any moisture in that system. IT has to be completely dry sand and it needs to stay that way. If not you will be sorry, it will destroy itself from pressure buildup.

[@SimpleTek]

Thank you!

[@natecus4926]

Very interesting idea! Would it be useful at all to put you solar heat collection things(I forgot what you called them) inside of the greenhouse as well? Or do they do ok in the cold even during the winter?

[@SimpleTek]

Evacuated tube solar heat collectors work in -30’ temperatures

[@natecus4926]

@@SimpleTek awesome, thanks!

[@williammitchell4084]

can i replace sand with a substrate that is more heat retentive? clay? clay balls? thank you so much for all your information!

[@SimpleTek]

Yes

[@poorwotan]

Wish this was reversible to get places cooler in summer and fall; even end of spring. Haha. Hello from the tropics...

[@SimpleTek]

Cheers from Manitoba, Canada I have a video on geothermal cooling in my archives

[@Happinessinlove777]

I have a very similar design, solar thermal sand/earth battery. I am designing systems for our dome homes and dome green houses

[@SimpleTek]

That's awesome! do you do this commercially?

[@davej7458]

How do you size your heat storage? How deep do you need or want to dig? Can the heat storage be under the green house planting beds?

[@SimpleTek]

good questions. I don't have a calculator, just guesswork at this point. There's a LOT of variables.... climate, soil conditions, insulation of your greenhouse etc...

[@Dominick13777]

Could you make a video about a diy sand battery for your home. I want to build a 1000 square foot home. A sand battery would be a great way to heat my home.

[@SimpleTek]

Actually doing that for my house right now!

[@Dominick13777]

@@SimpleTek keep me informed on this project. Very interested. 👍

[@SimpleTek]

@@Dominick13777 will do

[@regun2434]

Thanks for visualising my plans 👍

[@SimpleTek]

You’re very welcome!

[@dreckken]

I love these videos! Well done Sir!

[@SimpleTek]

Thank you!!!! I appreciate the comment!

[@TunekoLtd]

I would make the heat with air to air heat pump that runs on solar panels is converted to hybrid heat pump so it can also heat water. You will get better overall efficiency with that system that those solar heat collectors which efficiency is 50-75%. Solar panels efficiency is 20% but the COP is 5-6 so overall efficiency should be about 40% better. As a add on extra you get cooling for the summer without the second loop under the ground.

[@SimpleTek]

Heat pumps are expensive

[@TunekoLtd]

@@SimpleTek you can get a air to air heat pump for 500€. System cost is not much higher than with solar heaters. If efficiency is 20-40% better payback time should still be faster.

[@bludaizee24]

I hit like & subscribe! I'm in Northern Alberta. I hope you're greenhouse is doing well & I'd love to see it!

[@SimpleTek]

Cheers from manitoba!

[@jakestinky7066]

Just found this channel, awesome stuff

[@SimpleTek]

Thank you!!!

[@johndube3422]

Instead of running the heated water through under floor pipes, how about through a radiator with a fan to blow warm air into say a non-heated basement or crawlspace. Would it provide enough heat to warm an 800sf room or a 1000sf crawlspace 2ft deep during nighttime hours?

[@SimpleTek]

Might work

[@user-ic2ug8ys1z]

😃🌱🐢 I have a question. If you can not dig because you live on a rock. Could you put your geo tube/pex inside barrels of water for cooling? Your thoughts on this idea... Thanks.

[@SimpleTek]

I wish I spoke emoji

[@user-ic2ug8ys1z]

​@@SimpleTekI don't spoke emoji either,I'm just a gardener. I love your videos. I just tagged the videos to active the algorithm.

[@dannyg8741]

Great! Where do you get the plans to build it? Parts list possibly?

[@SimpleTek]

Don't know, maybe I should make one up some day

[@8thsinner]

Looks like a good concept, proven concepts made cheaper is always good. Btw, I meant to ask before, have you considered high focus heating like fresnels and wax as a thermal mass?

[@SimpleTek]

Yes I have, and high temp storage. I have videos in my archives on this. Thank you!

[@shandor2522]

Why wax, is it better than water somehow?

[@SimpleTek]

@@shandor2522 wax’s melting point is about 60’C, a useable temp! there’s a huge amount of energy in a phase change

[@8thsinner]

@@shandor2522 Some waxes take a very long time to melt and have much much higher temps to get there which hold their heat for much longer. I actually got the tip of a russian or alaskian or something but can't remember the details beyond they used a wax vessel over their hotstove furing the day then took the pot to the bedroom at night.

[@Dominick13777]

Could you replace the dirt with sand? Also, I thought about using a mini split to charge the battery in the summer as I cool my home. Instead of exhausting the hot air in the atmosphere it would exhaust to the sand battery. All comments welcome.

[@SimpleTek]

Yes

[@dienekes4364]

I'm actually more interested in geothermal cooling. I live in the Pacific Northwest and it doesn't really get that cold. I think just using solar heating is about all I need, but the cooling in the summer is much more important to me.

[@SimpleTek]

I already did a video on that, it’s in my archives

[@dienekes4364]

@@SimpleTek Yep. I've already seen it. Love your content!

[@SimpleTek]

@@dienekes4364 thank you!!!

[@naveedutp1]

hi, its great what you did, i have few question if you can help to answer, i am only concerned about cooling, not heating, 1. what is your ambient temp in summer, second what is your ground temperature at outlet when water runs via coil inside ground ? 3. if the temperature is x at outlet then how many degree it bring down your room temperature, and 4, what is your room temperature, appreciate for your help

[@SimpleTek]

Thank you , my ground temperature 10 feet down is about 5’ in winter and 7-8’ in sumner . Don’t really know how to answer the rest as they change based on the day and season year to year

[@naveedutp1]

@@SimpleTek thanks for reply, we have huge power shortage issue and i am interested in going with this solution, i m just concerned if my room temperature is 37 C and my water temperature is 24 C, how far this can bring down my room temperature, any rough idea so i can proceed for it

[@SimpleTek]

@@naveedutp1 good question, you should be able to cool 10’ with that

[@naveedutp1]

@@SimpleTek so when you are saying 10' means 10 celsius, if celsius then its great,

[@SimpleTek]

@@naveedutp1 consider evaporate cooling as well if your humidity is low, much cheaper than geothermal

[@IsaacLeath]

Do you need an overflow tank for when the water expands on a hot day? Is this a completely sealed system or does there need to be like an open tank where air can escape if it gets in the lines?

[@SimpleTek]

Good point

[@SolsticeOnAnOdyssey]

'or you're going to watch more Kardashians" hilarious LOL

[@SimpleTek]

Hehe

[@iam4iamWe]

QUESTION: How do I do the reverse in South Texas. I need cooling in the summer, and only 2 weeks on average of heating. Brilliant idea use of air-crete. Would I bury pipes and blow air through them for cooling?

[@SimpleTek]

Depends on your ground temperature a few few down where you live

[@olafschermann1592]

How to calculate the size of the earth battery?

[@SimpleTek]

@@olafschermann1592 I just guess

[@ehombane]

So how it worked out your system after one year? I always dreamed of such a system, but I live in a concrete box. But my idea was for the battery to be under the greenhouse. and the between battery and heated floor should be an grid like floor. aircrete for piles, and removable polystirene the rest. During the summer, the insulation will prevent overheating of the green house and lose of heat. During winter, insulation removed.

[@SimpleTek]

Works great

[@ioda006]

My grandpa dug his entire basement with a shovel and a bucket. Built his house in 1 year working on it after he got home from his factory job.

[@SimpleTek]

Wow

[@alisgara]

I'm very happy the algorithm found you :) How can I calculate the volume of water required and the temperature it would need to be to keep the averagely insulated 2000 sq house at 70 degrees Fahrenheit with an outside temperature of 30 degrees for a 72 hour period?

[@SimpleTek]

good questions, there are online calculators or that if you search google

[@ds9902]

I was thinking of installing a 325 gallon tank instead of looping pex. I'm thinking that it would leave more time to heat the ground. I was thinking and have been looking into everything else that you talked about.

[@SimpleTek]

that would work with a lot of insulation around it... ibc totes are cheap!

[@jameskrisp3911]

building one now I'll let you know how it turns out thanks

[@SimpleTek]

please keep me informed!!!

[@kchong0502]

You mentioned creating an insulated waterproof box out of Aircrete for the underground pipes. Wondering what's the appropriate general dimensions for it to work? Can the insulated waterproof box be maybe 1 foot high?

[@SimpleTek]

height isn't as important as total volume

[@kchong0502]

@@SimpleTek if that's the case, why not just wrap the pipe with insulated waterproof tape wrap?

[@jktriple_g_129]

This is awesome 🔥🔥🔥🔥👍👍🌳

[@SimpleTek]

Thank you!

[@GuentherJohnny]

Great ideas. How about a house with greenhouse attached, south face being transparent. Water tank under greenhouse floor as Geo battery. Heat collecting ducts at the high end, blowing through pipes in water tank. This tank would naturally release some heat into house in winter. This clean water could also be used for showers and what not. I wasn’t sure though if I would gain by insulating the tank. Especially the bottom. If it’s not insulated the heat could expand into surrounding dirt, effectively expanding the battery.

[@catprog]

8 feet * 100 feet * 2 feet / 1 yard = 59 days (from what I can tell 1 cubic yard is 8 hours of digging) -- 8 feet * 100 feet * 2 feet / 350 cubic yard for the excavator = 0.16 days. Excavator hire seems to be $450 / day Assuming you work a minimum wage job and taxes(+fuel to get to the job) take out half of that. It would take you 15 and half days to get enough money to hire the excavator. -- Conclusion: digging with a shovel is nearly a quarter of the speed as hiring an excavator once you factor in the time taken to earn the money to hire the excavator.

[@SimpleTek]

Buuuhahahahaha Clearly you’ve never used an excavator

[@driqbal316]

Amazing information. Thanks for sharing!

[@SimpleTek]

Thank you soo much for the kind words!

[@ronaldsahn9649]

Cheep simple solar collection could be just a black steel pipe hung inside the greenhouse with a half round shiny surface behind it and reflect on the pipe and a solar water pump. Also if you Buried a insulated water tank in the ground and Circulated your hot water through it all day through your rain cachment tanks.

[@SimpleTek]

interesting idea BUT black pipe wouldn't get the temperatures needed. You need evacuated tubes or parabolic troughs to get the water to near boiling temperatures

[@tangobayus]

First, orient the long side of the greenhouse East to West. Then insulate the north wall, which contributes nothing.

[@SimpleTek]

Absolutely, I have several videos on that in my archives

[@luigiaqua2263]

You’re wrong. Reflecting sunlight is also welcome. But usually underestimated.

[@davidbuck1614]

I've always liked the idea of motherships where your house is built into the north length of the greenhouse or a barn, you get some decent insulation but heat loss keeps animals in barns warmer.

[@tangobayus]

@@davidbuck1614that's a good approach, too. very few people seem to understand that the all-glass greenhouse is a disaster in terms of heat gain and loss.

[@duncanouellette3111]

I live just south of calgary and plan on installing a pex geothermal loop this summer and would love to pick your brain if you ever have some time

[@SimpleTek]

Sure!

[@justinsane7128]

So if you had a bypass on your solar panels would this also be able to be used as a summer cooler in a home

[@SimpleTek]

you'd need a separate dig, but yes. I have a video on that in my archives actually

[@justinsane7128]

@@SimpleTek I'm in Colorado and we use flood irrigation water on our pasture where this would be located would that affect things that this would be basically irrigated a couple times a week from June to October? Stainless steel everything I guess and Poly

[@aaronflynn5449]

Check out Polar Night Sand (thermal) battery system in Norway. I like your "Cheap and simple" application of the same ideas on a smaller single greenhouse?garage. I think your yersion could work on a small home also. Thank you!

[@SimpleTek]

Thank you

[@lse4709]

If it hasn't been mentioned already, a WRB type generically referred to as "peel and stick" could easily be used on the walls and roof of the aircrete to waterproof. Choice 2 - spray barriers by PolyGuard. Also Stego water barrier that is used under house slabs to waterproof both slab on grade and pier foundation systems would work brilliantly to eliminate water penetration into the aircrete. But now you have a waterproof Vault of soil with your coiled pipes filled with glycol that has been decoupled from the Earth around it. I'm sure this has implications for the quantity of heat held within the coil battery system

[@SimpleTek]

Interesting

[@oakld]

It's a must. Although the aircrete, at least Xella Ytong we use here most, doesn't break apart when it gets wet, it looses most of its insulation properties. And the insulation properties are not great to start with - they're good, but much worse than those of dedicated insulation materials.

[@mireillealbert]

Very astute, thank you. It makes me think - my friend's land sits on an old mountain lake bed that still holds a substantial amount of water under the soil surface. About twice a year during large rain storms or snow melts the water table rises and floods the land for a day. I could easily see a sealed, buoyant heat battery such as you describe being pushed up and broken up by the upwards water pressure. I'm thinking that perhaps one could, in order to lower the buoyancy but still achieve some insulating effect, use a clay barrier instead of quickcrete? It would certainly lower the rate of exchange with the surrounding soil. How much R power though, I wonder. Also to further address differences in buoyancy perhaps I would wet down the heat battery fill with water, thus creating a sort of soil-water pool that wouldn't easily be moved about.

[@SimpleTek]

@@mireillealbert great idea

[@oakld]

@@carguy221 Styrocrete is not a thing for walls bearing a load AFAIK, you can make insulation layer with it (but with much worse properties than dedicated insulation like EPS) or infill panels, which are kind of sweet spot for them, since the insulating value is good and they hold their form and only bear their own weight. However, I don't know (I'm not saying there aren't any) any styrocrete-like product on the market and if you had the DIY panels in mind, just estimating I'd say professional aircrete products like Ytong Lamda IQ have at least as good insulation values as the DIY styrocrete. And legally, their load capacity is 0. In fact, my friend is finishing a new house made from that product with 0,5m walls and he has no insulation, just render on top of the aircrete walls. He has no trouble satisfying our strict code, even stricter for him, since he's at higher elevation. Don't get me wrong, I'm not against styrocrete, but it's a different type of product for different applications.

[@-whackd]

Dumping a huge wood chip / leaf compost post pile on the north side of the greenhouse, combine with computer fan and battery to move the heat, and I'll have a warm enough greenhouse in BC. That's much simpler and easier.

[@SimpleTek]

You don’t get that cold there

[@-whackd]

@@SimpleTek that's right, I live right on the coast so I only need it to be about 5 degrees c warmer most winter. I heard a rocket mass heater is nearly free heat for people experiencing the continental winter.

[@Crashbangable]

The solar, heated houses I’ve seen have a insulated storage tank inside the mechanical room. Trying to store your heat energy in the ground outside of the greenhouse seems like a huge waste. Maybe I’m underestimating the cost of the storage tank. My first thought was to circulate from the solar heat collector directly to the in floor pex. Might overheat during the day and not enough storage for the night.

[@SimpleTek]

Has to do with the amount of input

[@alandolan2182]

If you don't want a pump in your system, use a gravity feed vacume system, it both draws water and pushes it. And valves will controll the flow of water through the system. No power required...

[@SimpleTek]

Good idea

[@ASDQWE-zs9rn]

Can you make a video showing how to make it step by step or at least detail blueprint?

[@SimpleTek]

Maybe….

[@CindySorenson-r4m]

What about off-gassing that system natuarally & safely? Any ideas?

[@SimpleTek]

@@CindySorenson-r4m what do you mean by off gassing?

[@Master-AGN]

Hi shied away from papercrete because it’s too messy. I just used equal amounts of vermiculite and sand. And the floor is warm even in the middle of winter.

[@SimpleTek]

@@Master-AGN cool

[@yohjokromwood2327]

can you do a video on solar dome desalting sea water

[@SimpleTek]

Cool idea

[@k.r.6800]

Question on the geothermal insulation. I get that the walls must be insulated to keep the heat inside the greenhouse, but i dont get the idea of insulation on top beneath the floor. If we lay down foam on top of the pipes where the irritation water will go if it's stopped by the insulated floor underneath the soil?

[@SimpleTek]

Foam should go under not on top of radiant pipes

[@jamesmckinnon6856]

would we have to install this below the frost line or would insulated walls be enough? it's 4' where i'm at in Ontario and can get to -33c at times. ;-)

[@SimpleTek]

Below the frost line unless it’s insulated

[@catprog]

Have you compared a flat panel hot water system instead of evacuated tubes? (their are some cheap DIY designs on you tube as well)

[@SimpleTek]

no but that's a good idea!!!!!!

[@michaelbarrett8803]

How much heat will this thing generate in the middle of the summer day after day. In the summer you would want to cover those evacuated glass tubes.

[@SimpleTek]

@@michaelbarrett8803 or just build up reserve heat

[@ArcherCanobra]

I live in Gainesville Florida just a few miles south of I-10. Lots of sand, some clay.

[@SimpleTek]

Ok

[@bradbrown2168]

Thoughts on Designing a new home. South facing but built into an existing hill or make a hill. So north side walls have less exposure and radiant heat from hill assists in ambient temperature. Getting light into North side rooms? Skylights or deep window recesses. I’d like to use your method as well. Thoughts on using hill energy?

[@paulcelona8442]

I like this design. do you have a parts list that I can use to build this?

[@SimpleTek]

Thank you for the kind words. Sorry I don’t sell plans

[@paulcelona8442]

@@SimpleTek I'm not asking to 'buy' plans, just a list of components you used to build this system. Can you post them in the description, please?

[@SimpleTek]

@@paulcelona8442 I don’t really have a list, sorry

[@juancortez4726]

Please please, no more Kardashian's videos!! lol!!... loved your solar boosted geothermal heating system!! thank you!

[@SimpleTek]

Cheers!

[@sherryallen3650]

Would you get different results if you put pipes under a tile bed or raised tile bed? Would depth requirements change? Liquid system of course

[@yaboimikeyp2453]

Thanks for saving us from the Kardashians :-)

[@SimpleTek]

Our pleasure!

[@michaelwellner6292]

I am a simpleton so Great!

[@SimpleTek]

Thank you

[@koeihiroko3622]

I find your video very informative but for a newbie like me who do not grasp the basic concept of geothermal cooling/heating, it would be more helpful if you can share the schematic of the build and explain in details how the system works, instead of just showing bunch of screenshots.

[@SimpleTek]

Thank you for the kind words! It might help to check out my archives and see the other videos I have on the subject

[@koeihiroko3622]

@@SimpleTek i think going forward, it would be even better if you can load the drawings in MSPaint and directly explaining / drawing how thing work. Like cold air goes here, heat goes out here, etc... otherwise it's pretty much sound like bunch of theory and concept, but not very in details and newbie friendly video

[@mdabbaskhan]

What kind of pump to use when pushing the windshield fluid down the tubes? I am lost. Do we use a simple water pump if there is a specialized pump for it?

[@SimpleTek]

there are special pumps like the taco pump or similar brands

[@bradbrown2168]

My thought is building a green house on south side of house and put heat pump in it. The air is so much warm so less work to get desired winter heat. I guess for summer build an old fashion icehouse, saw ice from a lake. plumb it so different seasons use different buildings. Thoughts? Use that with geothermal battery?