This is a hodge podge of topics, but one of the key aspects of this is the solar powered. I would like to be a very well insulated room on a 8'x14-16' flatbed trailer to serve as an above ground root cellar. Walls and floor will be r-30, ceiling r-50. It will very likely be pretty noise proof also. At first I was thinking of putting a chest freezer or two inside with a new thermostat set to 50 degrees. Option 2 is to not use chest freezers inside - unless it is actually to freeze something but to keep the entire room chilled to 50 degrees. Chilling would be done with 2 window a/c. One is probably enough for this size room, but the second one would serve as a backup. I have seen "thermostats" that make an a/c function as a freezer in a walk in unit. Basic, absolutely must requirement: to be able to power this thing from the sun. Do you think 72 sq. ft of solar panels can make this work? I would put batteries in for 2 days of operation, but really, when the sun doesn't shine, it is usually not so hot, so the a/c would not be in use. Any suggestions? A stupid idea? I will not be in a position to consider underground or in ground storage for the next 3 years, but I want to reach my food lts goals in about 3 years.
Solar powered "root cellar"
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If you want to cut down on power requirements, double your insulation!
R 30 and r50 are allready really good insulation. Shading the area it’s parked in would help too. To answer your question on energy requirements you first need to find the cooling unit and see what it’s requirements are. There’s loads of refrigerated truck units out there. Try to get a look at one of those and then you design the solar setup for that.
I looked into refer units by accident some years ago - expensive because they are not run of the mill, and parts are even more expensive. Also many run on diesel or fossil fuels. I have seen some ads for a "thermostat" that can be used with a household air conditioner to make a walk in cooler. It is similar to the device that is used to make a chest freezer into a refrigerator. I need to learn a bit about heat transfer, etc...a little bit of physics.
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CoolBot Walk-In Cooler | How to Build a DIY Walk-In Cooler This is what I am talking about - the thermostat to use an a/c unit as a walk in fridge.
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Hmm. . . Have to wonder if that doesn't make sense for us southern states that live too
close to the coastline and a root cellar is not an option. This is what I found
close to the coastline and a root cellar is not an option. This is what I found
..... not to sound tew gross... but does anybody know-how to defeat rodentus in said 'walk-in-cooler/pantry' for good?
....justn ya know, lil sick of parasitus rattus and other mundane stuff , ya know...
...do u add a window AC to drop that ' start up' temp....hmmmm
Need a little advice from you root cellar people. In about 6-12 months my acreage should have everything ready for 2nd stage prepping to begin (root cellar, Garden, etc). Phase 1 is solar water, solar refrigeration, septic, fruit trees, large travel trailer, misc. fencing and catfish stocked ponds...
but I would like comments on what I plan for cool LT food storage. I plan on burying two Norwesco Bruiser Single Compartment septic tanks (11' x 4.5' x 5.5' high). Installing air vent hook pipes to promote air flow with insect screens and assist the flow with a little solar powered fan forcing hot air (high vent) out, thereby creating a vacuum effect in the tank bringing in cooler air. (As cool as it can get in Texas)
Do any of you with experience see any problems with this concept? I freely admit I am out of my depth on root cellars! or any other cooling methods that do not require heavy (A/C) techniques.
Any advice is appreciated
but I would like comments on what I plan for cool LT food storage. I plan on burying two Norwesco Bruiser Single Compartment septic tanks (11' x 4.5' x 5.5' high). Installing air vent hook pipes to promote air flow with insect screens and assist the flow with a little solar powered fan forcing hot air (high vent) out, thereby creating a vacuum effect in the tank bringing in cooler air. (As cool as it can get in Texas)
Do any of you with experience see any problems with this concept? I freely admit I am out of my depth on root cellars! or any other cooling methods that do not require heavy (A/C) techniques.
Any advice is appreciated
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Through the years I’ve seen and used different root cellars. Never has there been a need for a fan, but never lived in Texas. How deep is your water table? If you can dig down where the bottom of your root cellar is 10 feet, you would have a very cool root cellar, even in Texas. How large is the opening on the septic tank? You need plenty of room to carry things in and out and an insulated door. You could pour a concrete bottom or my preference a gravel floor, and use cement blocks for the sides...well coated with water protection. Be sure to dig a trench around it with a hose to carry away water.
Be sure to put in 2 vents. One toward the bottom to bring in air, the other out the top to expel the ethylene gas. These should be 3 to 4 inch pipes.
Water table is no issue. I was planning on 10' depth. The tanks have 2 manways for maintenance each but food would have to be lowered down these manways as this would not be a walk in cooler but a buried tank, I am trying to avoid massive costs in trying to build an concrete cellar. yes two air vents per tank, one high one low. One of my unanswered questions is if the ambient temperature of the air is warmer than the temp at 10' depth would a vent system just warm up the food storage? I am wondering if the ventilation might work against me in the summer time. I told you I was less than ignorant 
In researching solar applications I have found the following two links very helpful. Remember when sizing solar always take into consideration your start up (cranking) Amps on all motor driven items.
https://www.altestore.com/store/calculators/off_grid_calculator/
https://rimstar.org/renewnrg/sizing_select_batteries_for_off_grid_solar_system.htm
I wouldn't be investing that $$$ into some temporary half-azz cooler unit >>> if you have space on your property for that unit - you can construct a building that has a full-time usage package besides being a cooler ....
Water table is no issue. I was planning on 10' depth. The tanks have 2 manways for maintenance each but food would have to be lowered down these manways as this would not be a walk in cooler but a buried tank, I am trying to avoid massive costs in trying to build an concrete cellar. yes two air vents per tank, one high one low. One of my unanswered questions is if the ambient temperature of the air is warmer than the temp at 10' depth would a vent system just warm up the food storage? I am wondering if the ventilation might work against me in the summer time. I told you I was less than ignorant
You are far from ignorant! With enough earth mounded over the majority of your roots cellar, there would be no problem. Not being able to walk into a root cellar is a problem. Did I get that wrong? Do you have a hillside you can put it in to?
not enough of a hill, more just s shallow slope grade(1':30'+/-)... good thing about advance planning is you get to "measure twice, cut once"... trying to hold this down to under $4K..just bouncing the ideas around now
David,
I'm also in central Texas. Our ground temps are in the mid-60's year round. But you will want to exchange air to avoid mold/moisture. You also need to make sure these will not fill with water. Some questions.
1) I assume you are not in hill country rock? So... east of I-35 by 'enough'?
2) Why 10 ft down? trying to avoid ___? (what?)
3) How much sq ft or cubic feet of space do you need?
4) What are you storing (generally speaking)? How often will you need access?
5) Would you see staying down there for hours/days/weeks?
Some thoughts. Not fond of septic tanks. Heavy duty, yes. But keeping water out is not their strong point. And access sucks bigtime. For ventilation, run a PVC pipe from the surface about 4 ft down and across maybe 100 ft. Have a fan that blows air downward into it (solar?). The 100 ft horizontal run will drop the air temperature to the soil's 65F temperature. More importantly it will reduce mold/moisture issues. Second pipe coming up for exhaust (or combine with your human-access point). Sloped walkway or staircase down will be worth it's weight in gold if you have to come/go often. Put this under a building or something for concealment. Have a way for moisture to get pumped out (if you know about sump pumps for houses with basements). If you need more room, consider burying a shipping container. But you will need to do cement poured walls around it (steel reinforced) to handle the ground pressure. Just my initial thoughts.
I'm also in central Texas. Our ground temps are in the mid-60's year round. But you will want to exchange air to avoid mold/moisture. You also need to make sure these will not fill with water. Some questions.
1) I assume you are not in hill country rock? So... east of I-35 by 'enough'?
2) Why 10 ft down? trying to avoid ___? (what?)
3) How much sq ft or cubic feet of space do you need?
4) What are you storing (generally speaking)? How often will you need access?
5) Would you see staying down there for hours/days/weeks?
Some thoughts. Not fond of septic tanks. Heavy duty, yes. But keeping water out is not their strong point. And access sucks bigtime. For ventilation, run a PVC pipe from the surface about 4 ft down and across maybe 100 ft. Have a fan that blows air downward into it (solar?). The 100 ft horizontal run will drop the air temperature to the soil's 65F temperature. More importantly it will reduce mold/moisture issues. Second pipe coming up for exhaust (or combine with your human-access point). Sloped walkway or staircase down will be worth it's weight in gold if you have to come/go often. Put this under a building or something for concealment. Have a way for moisture to get pumped out (if you know about sump pumps for houses with basements). If you need more room, consider burying a shipping container. But you will need to do cement poured walls around it (steel reinforced) to handle the ground pressure. Just my initial thoughts.
The air flow will loose some of the cooler air but without the flow you will have too much moisture buildup and as GP said ethylene has too.Water table is no issue. I was planning on 10' depth. The tanks have 2 manways for maintenance each but food would have to be lowered down these manways as this would not be a walk in cooler but a buried tank, I am trying to avoid massive costs in trying to build an concrete cellar. yes two air vents per tank, one high one low. One of my unanswered questions is if the ambient temperature of the air is warmer than the temp at 10' depth would a vent system just warm up the food storage? I am wondering if the ventilation might work against me in the summer time. I told you I was less than ignorant
A small fan with a solar panel would be enough to move air. You don’t need a big setup. I just use natural airflow in mine With a low and high ven.
I did a whole post with pictures of the root cellar I built. I didn’t have anywhere near 4 grand in it but did have a lot of my labor and time on the weekends. It’s in the old threads here.
Texas
1. Near Nacogdoches.... no bedrock
2. 10'+ depth earth is stable 70 degree temp +/- 5 degrees in our area
3. difference between need and want I guess . this would give me approx 500 cf storage
4. anything that last longer with dry, dark, cool storage from garden veggies to LTS freeze dried canned goods
5. not Staying down there at all. just storing and retrieving... minutes per usage
Norwesco Bruiser Single Compartment septic tanks are one piece moulded plastic. Designed reinforced to be buried w/o filling full of water. Mainly wondering it would defeat the purpose to have surface air being drawn down into and environment that should already be cooler due to surrounding ground temp at 10' depth. Water table around 25' down in my location.
The fan would be mounted at the bottom of the hot air evac vent pipe down n the tank. The power wire would be fed up the vent to a solar panel on the surface.. Sun shine, fan works... no on/off. forcing the air in the tank up and out the top and resulting in the intake vent drawing in the outside surface air into the tank.
BUT in our summers that air may be at a higher temp than the air in the tank 10' below ground. I am just starting to think this through now and solve the problem foreseeing any drawbacks. Maybe install a on/off switch on the fan, turning it off in the summer and on in the winter? IDK maybe I am overthinking this... I tend to do that sometimes. It is the curse of my profession
PS the cost is excavating and filling the hole ( 1 day on excavator) and the two 1500 gal plastic septic tanks. Solar would probably be less than $150// too old for the do-it-yourself route
PPS running the intake vent pipe approach is interesting
1. Near Nacogdoches.... no bedrock
2. 10'+ depth earth is stable 70 degree temp +/- 5 degrees in our area
3. difference between need and want I guess . this would give me approx 500 cf storage
4. anything that last longer with dry, dark, cool storage from garden veggies to LTS freeze dried canned goods
5. not Staying down there at all. just storing and retrieving... minutes per usage
Norwesco Bruiser Single Compartment septic tanks are one piece moulded plastic. Designed reinforced to be buried w/o filling full of water. Mainly wondering it would defeat the purpose to have surface air being drawn down into and environment that should already be cooler due to surrounding ground temp at 10' depth. Water table around 25' down in my location.
The fan would be mounted at the bottom of the hot air evac vent pipe down n the tank. The power wire would be fed up the vent to a solar panel on the surface.. Sun shine, fan works... no on/off. forcing the air in the tank up and out the top and resulting in the intake vent drawing in the outside surface air into the tank.
BUT in our summers that air may be at a higher temp than the air in the tank 10' below ground. I am just starting to think this through now and solve the problem foreseeing any drawbacks. Maybe install a on/off switch on the fan, turning it off in the summer and on in the winter? IDK maybe I am overthinking this... I tend to do that sometimes. It is the curse of my profession
PS the cost is excavating and filling the hole ( 1 day on excavator) and the two 1500 gal plastic septic tanks. Solar would probably be less than $150// too old for the do-it-yourself route
PPS running the intake vent pipe approach is interesting
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The septic tank should already have 2 holes for ventilation, that being the inlet and outlet holes for the septic lines. Although both holes are usually high so you may need to drill one for the lower pipe. You can rent a core drill from Home Depot and they are easy to core drill, I use to cut concrete for a living and cored many a septic tanks! For having to lower your food down in them, see is you can attach a ladder in one of the maintenance holes. I have actually thought about putting another septic tank next to my "real" septic tank and store some of my preps in it, especially guns, so if big brother came knocking, it would just seem like another septic tank. Even if you bury it deep, you can install a metal box, the size or a little bigger, than the maintenance hole you plan on using. Sit it over the lid, have a top for the box, then cover that up with just a few inches of dirt to hide it. You then will not need to dig that deep to reach the lid.
TexasFreedom had a good idea on running the pipe a good ways. It will help cool the air but also keep eyes away from the actual location! maybe even put it in thick of trees, shrubs or I have even seen a guy who used a ventilation pipe as the base for a big bird house!
Didn't know they were plastic, disregard the core drilling part!Texas
1. Near Nacogdoches.... no bedrock
2. 10'+ depth earth is stable 70 degree temp +/- 5 degrees in our area
3. difference between need and want I guess . this would give me approx 500 cf storage
4. anything that last longer with dry, dark, cool storage from garden veggies to LTS freeze dried canned goods
5. not Staying down there at all. just storing and retrieving... minutes per usage
Norwesco Bruiser Single Compartment septic tanks are one piece moulded plastic. Designed reinforced to be buried w/o filling full of water. Mainly wondering it would defeat the purpose to have surface air being drawn down into and environment that should already be cooler due to surrounding ground temp at 10' depth. Water table around 25' down in my location.
The fan would be mounted at the bottom of the hot air evac vent pipe down n the tank. The power wire would be fed up the vent to a solar panel on the surface.. Sun shine, fan works... no on/off. forcing the air in the tank up and out the top and resulting in the intake vent drawing in the outside surface air into the tank.
BUT in our summers that air may be at a higher temp than the air in the tank 10' below ground. I am just starting to think this through now and solve the problem foreseeing any drawbacks. Maybe install a on/off switch on the fan, turning it off in the summer and on in the winter? IDK maybe I am overthinking this... I tend to do that sometimes. It is the curse of my profession
PS the cost is excavating and filling the hole ( 1 day on excavator) and the two 1500 gal plastic septic tanks. Solar would probably be less than $150// too old for the do-it-yourself route
My fault, I wasn't descriptive enough. We have been getting away from old concrete septic tanks around here for few years now. We can get the plastic ones pretty cheap, but you have to fill them up with water before backfilling (except for the Bruiser tanks I cited)...A 500 gallon non-reinforced plastic septic tank (must fill with water before backfilling) is only $650..... beats the hell out of a 500 gal concrete tank!..... of course you must make sure you aren't in expansive clay territory! these are good for sandy loamy conditions
PS.. Texas might just be on to something running that intake horizontal at depth allowing the outside air to be cooled before it enters the tank. I hadnt thought of that
PS.. Texas might just be on to something running that intake horizontal at depth allowing the outside air to be cooled before it enters the tank. I hadnt thought of that
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So the power just connects directly to your existing main panel with nothing else in-between?! Is this because the microcontrollers stop sending power when city power goes out?
The reason you have to fill them is that the water gives a counter-pressure to support the walls. If you ever empty the tank, it has a real risk of collapsing. Oops. Reconsider concrete,
The horizontal pipe absolutely works, a friend with an underground house uses that idea with good success. Don't drill extra hold, put an 'adapter from the existing intake and just add a pipe inside to take your incoming air to floor level.
No reason to go 10 ft deep, is there? 2-3 ft of soil on top should be plenty. If worried about heat coming down, put a sheet of foam insulation on top and cover that with a sheet of FRP or even better aluminum. You will kiss this old ugly man if you have to go down/up 100 times (10 ft fs 3 ft).
Yeah That is the reason why I am NOT going with non reinforced plastic tanks, I kind thought the freeze dried stuff and veggies might get a little soggy.
Dont think I'll need to access that often and that's what the rest of my family is for anywho.
Tanks:
https://www.norwesco.com/products/waste-water-tanks/bruiser-tanks
PS.. I'll be burying my actual septic tank this summer, so I will get to see the soil temps at depth in the height of the hot season. I'll see then what 6' down reading on the thermometer
Dont think I'll need to access that often and that's what the rest of my family is for anywho.
Tanks:
https://www.norwesco.com/products/waste-water-tanks/bruiser-tanks
PS.. I'll be burying my actual septic tank this summer, so I will get to see the soil temps at depth in the height of the hot season. I'll see then what 6' down reading on the thermometer
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When you first mentioned it, I envisioned exactly that hook-up. Damn good idea I think
You might want to verify why this statement is on their website:
- Once in the ground, must be kept 1/4 full at all times.
