Low Power Cooler (root cellar)

[PowerGuy]

We had a serious problem with our potatoes, beets and carrots, harvested this fall, in that we had no root cellar to provide long term storage (seed stock for 2010 also!). Searching this forum and others, we encountered the idea of using a chest freezer with an external T-stat in "refrigerator" mode. We used a 15 cu. foot chest freezer and a Dayton TLH106 (Grainger 2NNR6), so that the contol would be external and the only penetration of the box would be via the small diameter capilary tube, laying on the rubber gasket, We also wanted to make sure that the control required no power when on stand by mode, unlike an electronic control (which pulls about 15 watts 24/7). The results are in! Temps are maintained between 43F and 48F, the system runs about 2.5 hours per day, and uses only 0.23 KWH/day. That works out to about $10 per year of power (which can be PV array sourced in our case, if needed). The humidity is holding at between 95% and 98%, nearlfy ideal for potato storage, and the tubers are looking great. Thus, for about $10 per year in energy costs, we eliminated the need to construct and expensive exterior root cellar and now have an interior climate controlled "root cellar" that will likley keep our food and seed stock for an extended period.

We want to thank all the folks on this forum and others that provided the idea for this easy to implement solution!

[DavidOH]

Now THIS is what this forum is all about. Sharing to find solutions.
I hope I can get such help when I have a problem to solve.

[PowerGuy]

We now have a temperature record over a period of day, showing that the Dayton caplillary (passive) temperature control, i.e., non-electronic, can control the internal temperture within a tight range. Run time is about 20 minutes and the coast time is about 3.5 hours. Thus, the run time is roughly 2.3 hours per day and energy consumption of about 0.25 kwh/day is consistent with this temperature record. The tubers continue to be in a literal state of suspended animation and we expect to have fresh food until the new crops come in next year!:wink:

We have uploaded a jpg of the temperature record, (if the upload worked)

[Pokeberry Mary]

When we lived in the north I always kept apples, onions and potatoes in bins-- or in the root cellar.

Since we moved here I had the darndest time keeping them fresh til a co-worker told me she keeps them in the fridge. now I do that.

I am hoping though that at some point my root cellar will cool enough to store them--but right now looks like its a no. I have a small dorm fridge I'm using to store some but I don't have them in the garden so that works for me at this time.

[NotSoFast]

This is a great idea. It not only solves the storage problem for those who live in the South and those whose water table prevents digging a root cellar, it give apartment dwellers a solution as well. I live in California in an apartment and have no way of keeping things cool in summer.

[PowerGuy]

If you are interested, thi is the way we did it, which worked very well indeed. This controller uses no power when in stand-by mode and just closes a contact when cooling is required. We wanted to use one that had a nice look that matched the freezer finish.

[Pokeberry Mary]

I need to show this to Hubby. He's the smart guy around here. I see techy stuff and my head sort of goes off in a different direction. ;)

I sure would love more storage for onions, potatoes and such like that don't last long in our new home climate.

I do have a root cellar-but keeping it cool is not going to be consistent--I can see that already. Its great for other storage though--and a storm shelter too.

[NCLee]

Mary, do some research on what can be stored together in a small space. For example, it's difficult to store onions and potatoes together. I made that mistake of trying to keep them in one of those wooden kitchen tater/onion bins.

Avoid storing potatoes with onions because, when close together, they produce gases that spoil both. http://www.ehow.com/how_3480_store-potatoes.html

Some more info that may be helpful. I haven't tried it so can't comment on how well it will work. http://www.ehow.com/how_4488705_store-potatoes-onions-over-winter.html

Potatoes and onions are one of many combos that can't be stored together for any length of time. Google apple storage to learn about the gas they give off that affects other fruits and veggies.

HTH,
Lee

[PowerGuy]

We have some experience with our freezer converted to cooler now, after several months of storing about 200 lbs of potatoes in sacks, with carrots and turnips in trays. We found that even with the cooler circuit set to 38F, the coils in the freezer box walls fell well below freezing with even only few minutes of run time. The solution was to line the freezer box with custom fit drop ceiling ventilation panels purchased at Home Depo (about $11 each).

If the potatoes are at room temperature when you place them in the cooler, we also recommend that you drop the temperature about 2F to 4F per step, over a period of 24 hours to prevent frost damage to the tubers closest to the walls of the freezer box. Once the box is stablized at the preferred set point, which we found to be about 38F to 42F, the 1/2" separation of the tubers from the cold sides, allowing air circulation, will prevent frost damage. If the tubers are packed in plastic baskets, this may not be necessary but that also severely limits the amount that can be stored.

[AlchemyAcres]

.....line the freezer box with custom fit drop ceiling ventilation panels....


That's a very clever solution!



~Martin

[oldie]

This has been a very interesting discussion.
Thanks