August 17, 2019

Solar Pantry Part 2: Analysis

Now what? In "Solar Pantry Part 1" I shared my calculations and conclusions about the feasibility of putting the fridge and freezer in my pantry on a small dedicated solar energy system.

A photo from my archives! This one of my pantry was taken in 2010
soon after we bought the freezer. The refrigerator came with the house.

The conclusion was that such as system would cost considerably more than my available funds at this time. That was not only disappointing, it also left me with a big question mark regarding my goal of minimizing food loss in the event of a prolonged power outage. I had to ask myself, are there other alternatives? How did people in my part of the country keep food before electricity? (I've mused on that topic before - see "Food Storage in the South.")

Dan and I have taken small steps toward a simpler, less complicated lifestyle, but we are still products of the 20th century. That means our solutions to problems are usually based in modern methods and technologies, simply because that's what we know. It's taken some time, but we've gradually been learning how to think outside that box. We've moved along with some of the 21st century's technological advances, and rejected others because they require more time and resources to maintain than we are interested in giving. While solar energy does take time and resources to maintain, it does seem like the best option for my goal. Now I had to ask myself, if I can't afford the technology what else can I do? Is there another way? Is there anything I can change?

As I pondered that, I had to question how I use my freezer and two refrigerators. So much of what we humans do is by habit, and habits form routines. We become so accustomed to our routines that we rarely question them. In the light of my goal, now was the time to question them. Have my routines caused me to be too dependent on my freezer and extra fridge? Have I fallen into inefficient habits? Is there anything I can do to make food processing and storage more energy efficient?

My first step was to make a list of everything I keep in these appliances. Then I asked myself why and categorized my list. Some items are listed twice because they are in more than one category.


To increase longevity:
  • dairy
    • milk (up to 10 half-gallon & quart jars)
    • butter (to keep it from melting)
    • cheese: fresh, brined, & stored in olive oil
    • kefir (1/2 gallon)
    • primost
    • whey (gallon+ for leavening, lacto-fermenting)
  • brine for cheesemaking (1/2 gallon)
  • eggs (6 dozen or more)
  • bread
  • some fresh fruit such as figs and berries for immediate use
  • vegetables: lettuce, greens, cut tomatoes
  • root veggies: potatoes, carrots, onions, garlic
  • condiments
    • ketchup
    • mayo
    • mustard
    • pickles
    • lacto-fermented: kimchi, sauerkraut, sauerruben
    • salsa
    • salad dressing
  • maple syrup
  • jams and jellies (opened jars)
  • peanut butter (natural, to prevent oil separation)
  • fresh meat
  • beverages except water
  • opened jars or cans of food
  • leftovers

To protect from insects:
  • pantry moths (always a problem):
    • flours
    • grains
    • bread
  • fruit flies (frequently a problem):
    • strawberries
    • blueberries
  • ants (occasionally a problem, items refrigerated as needed)

For long-term storage (such as a year's supply):
  • onions
  • garlic
  • eggs
  • rendered fat

To save until I get enough to process:
  • green beans

To stock up (because I found a deal I couldn't pass up):
  • case of organic coconut oil mayo (75¢ per pint jar!)

Livestock and garden supplies:
  • veterinary antibiotics & vaccines
  • essential oils
  • homemade insect spray
  • garden seeds
  • bulk seeds for pasture and hay


Preservation (for hopefully a year's supply)
  • meat
  • cheese: grated mozzarella, paneer, halloumi
  • primost
  • powdered rennet
  • cream
  • goat colostrum
  • berries (for smoothies, pancakes, and oatmeal)
  • melon chunks (for smoothies)
  • pureed winter squash
  • okra
  • chopped peppers

To save until I get enough to process:
  • bones for bone broth
  • fat to be rendered
  • tomatoes
  • blueberries
  • strawberries
  • figs
  • fruit juices from small batches of fruit for mixed fruit jellies

Convenience foods
  • unbaked pies
  • breads, baked goods
  • jars of leftovers for winter soups

To protect from insect damage:
  • flours
  • breads and crackers
  • grains (up to 50 pounds or more of homegrown grain)
  • nuts (mostly in-shell pecans from our trees)
  • bulk seed: grain and pasture seed

It's the only way to keep:

The thing that stands out most to me is that many of these items don't actually need to be kept in the fridge or freezer. That's just been the way I've addressed my food storage challenges.

My primary challenge is our temperatures in summer, especially July and August. After we get a string of days in the mid-90s°F (35°C) outside, my kitchen and pantry temps gradually rise to about 85°F (27°C) during the day and drop to around 80°F (27°C) at night. When we get to about 100°F (38°C) in the shade outdoors, my pantry thermometer can reach 90°F (27°C). Not an ideal temp to store food.

This is why I refrigerate items that wouldn't otherwise need refrigeration. (You can find a list of these at the Farmer's Alamac website.) Unwashed eggs, for example, have their own protective coating called the bloom, which keeps them fresh without refrigeration. Even so, I know from experience that summer eggs I refrigerate immediately will keep all winter for me, whereas eggs left on my countertop in summertime will start to fail the float test before autumn arrives. That points to my temperature problem.

Until I started looking into shelf life, I didn't realize there is a formula to describe it! Called the Q10 temperature coefficient, it's defined as the measure of the rate of change in a biological or chemical system for every 10°C (18°F) change in temperature. Starting with a baseline of "room temperature" or 22°C (72°F):
  • For every 10°C (18°F) increase, shelf life is halved. 
  • For every 10°C (18°F) decrease, shelf life is doubled. 

You can see why storing even canned and dehydrated goods at cooler temperatures is important. And that makes me realize that I need to address more than just the fridge and freezer.

My other big problem is pantry moths. They infest not only grain products, but they also love dried fruit! I can't tell you how much food I had to throw away before I started dry-pack vacuum canning most of my dry goods. (How-to here). But that only covers quart and half-gallon amounts, and I also have moth problems with the bulk grains we grow and the farm seed we buy. Even the barn isn't safe from them, so bulk quantities end up in the freezer.

If you're still with me, you might have noticed was my "To save until I get enough to process" category. This is because my food production is small scale. I don't have a huge prepper's garden; in fact, I've downsized my garden quite a bit over the years to keep it one-person manageable. Besides, I don't have a crowd to feed, it's just Dan and me.

One example of this category is tomatoes. When I harvest tomatoes, I don't pick them by the bushel, I get a dozen or two at each picking. That isn't enough for a canner load of tomato sauce, so I toss my tomatoes into the freezer and then process and can later in the year. This routine works very well for me, even to the point of draining the water from my defrosted tomatoes and using it to can tastier dried beans. Plus I don't mind waiting until cooler weather to do some of my canning.

Some folks tell me I'm overly analytical, but identifying the factors involved and closely examining them is the only way I know to problem solve. In looking over my list, one thing that stands out to me is that of all the items listed under "refrigerator," all but the dairy category could be stored elsewhere. And actually, that could be too if we had the right resources. For now, I'm researching and collecting ideas. Some old, some new, but all with a view to develop a plan for better food storage. I'll share what I come up with soon → Solar Pantry Part 3: Alternatives


arta said...

Hi, I want to share our experience with solar, hoping it might help you in your research. We live completely offgrid with ONLY solar to run our house (small house). We opted years ago to let go of our refrigerator and use a small chest freezer in its place. The small chest freezers have a 'refrigerator/chiller/freezer' setting and we run ours on 'chiller'. When I open the 'chiller', the cool air does not fall out, so it uses a LOT less power than a refrigerator to keep it cold. At the bottom of the 'chiller', we have bottles with our drinking water and that keeps a cold mass in there at all times. We run it on a timer as well. It turns on at 9am and off again at 4pm and we've never lost food out of it. The water at the bottom keeps it cool overnight. Our big chest freezer is used as a freezer and it is packed full. The top layer is a row of water filled soda bottles (lying on their sides) and that means we can also run the freezer on a timer. On at 8am, off at 4pm and we change the time it turns off in summer when we have sunlight later in the day. We never open the freezer after 2pm anyway and the soda bottles keep everything frozen. This way we're using a lot less power and have been able to get by on a very small solar system. We found that companies wanted to sell us the biggest system they thought we needed.... business is business I suppose, but we did not need to go that big. What we easily forget is that both the chiller and the freezer do not run all the time, they switch on an off during the day to maintain their temperature. I realize that some people will be aghast at the way we use these appliances, but if you take our way as the one extreme and your current way as the other, you might find something in the middle that works well for you :)

arta said...

I was not clear in my comment :) The water filled soda bottles we have in the freezer, freeze solid. That means the top layer of our freezer is like a block of ice that keeps it cold overnight when the freezer is off.

JayNola said...

Arta's usage model above is exactly what I was attempting to convey.

Leigh said...

Arta, so basically you have a minimally powered old fashioned "Ice Box". Is that correct? What an excellent system. Exactly the kind of thinking outside the box we look for. Except seeing how someone else does it saves us from our inevitable trial and error as we try to figure something out. I wonder if you have daytime temps similar to ours, but experimentation I'm sure we could figure it out. We've already decided this project is about more than just the fridge and freezer. If we can manage to get my pantry cooler (and/or build a root cellar) for most of those items, I wouldn't need as large a fridge for my milk, so your idea would probably work well.

JayNola, thank you!

Leigh said...

Arta, my husband is curious about your system. He's curious as to the number of panels, size of your battery bank, and how much electricity your using. You've obviously been able to adjust your lifestyle, and that's the kind of information that's really helpful.

Sandi said...

"Dan and I have taken small steps toward a simpler, less complicated lifestyle..."

This is freedom.

Leigh said...

Sandi, amen.

Mama Pea said...

Yikes! What an eye-opener (again!) as to how very different our climates are and the "problems" created (and work involved to overcome) in order to live in a self-sustainable, healthy, environmentally sane and sensible way in our different geological settings! Sets my mind to wondering whether more people think you and Dan or Papa Pea and I are crazy for choosing to live where we do! ;o)

Lady Locust said...

Hi Leigh,
Growing up, we had a cold room out in the wood shed. The walls and door were about a foot thick and I believe filled with sawdust. Even mid-summer, if we had to get something out of there, it was cool. Is there a closet you could insulate? Or is there a space in one of your buildings?
* I know sawdust is a fire hazard but was commonly used as insulation in the past- perhaps a safer option would be better but I bet with the mill, you could supply your own sawdust.

Cockeyed Jo said...

Most of what I saw on your list can be canned (figs,strawberries,blueberries, rendered fats,milks, etc). We keep our seeds, flours,grains,nuts in mylar bags with oxygen absorber in metal trash cans. There is a 2 ingredient ice cream (whipping cream ...RediWhip and canned sweetened condensed milk)Make smaller batches of bone broth and go ahead and make your soups, and can them. I believe goat colostrum comes in powder form or dehydrate it yourself. You can also dehydrate cheese.

When we lost everything in our freezer, it was mostly ground beef(Mel doesn't like the texture of canned ground beef- 30lbs),a case of chicken thighs (40 lbs) for grilling, corn on the cob (1/4 bushel),the spring lamb that I hadn't got around to canning yet, hot dogs (20lb), beef, lamb,and chicken bones, spinach and greens (I don't can these because of the loss of texture that I like), 2 lbs of bacon and sausage I hadn't canned yet. As they thawed I did can some of it.

Like suggested we lined the whole freezer with 2 l frozen bottles, but didn't have the solar back up.

All the things I canned or dehydrated carried us through. Cockeyed Jo

Unknown said...

This is very interesting subject as I would like to do something similar. I have read about using the chest freezers for frig. I would love to hear more info! Thanks, Brenda

Leigh said...

Mama Pea, I think crazy is a relative term! lol Honestly, I don't know if there's a perfect place; each location has it's own positives and negatives. To me, "successful" homesteading is learning how to deal with regional challenges either by finding solutions, workarounds, or just accepting them as they are.

Lady Locust, what you describe almost sounds like an ice house. My folks' friend had a cabin on a lake in Wisconsin that had an old )no longer used) ice house. They harvested ice from the lake and packed it in blocks in sawdust. Obviously, the slowly melting ice kept it from being a fire hazard!

Right now one of the options we're discussing is better insulation for the pantry. It was added on to the house some time after it was built, and it's really one of the hottest rooms in the house. I think that would help a lot.

Jo, I'm glad to hear you were able to save at least some of what you had in the freezer.

I'm not trying to eliminate the freezer and fridge, nor am I wanting to increase my workload by canning single jars of tomatoes, blueberries, green beans, of bone broth etc. One thing I would definitely not want to can is milk. I know it can be done, but canning would be problematic for making cheese, which is what I do with my milk except for kefir. High temperatures (like pressure canning) destroy the protein molecules so that they can't form curds. Two or three gallons of milk at a time is good for me for my cheesemaking. Definitely never buy powdered colostrum unless your kid or lamb is on the verge of starving to death. It's not colostrum, just powdered milk and chemicals with the unfortunate side effect of diarrhea. I've been looking into the mylar bags and 02 absorbers for bulk, but am not especially keen on things I have to replace as I use them, nor on heating up a gadget to reseal the mylar. Still it's an option and we haven't entirely ruled it out.

My bigger concern after doing this analysis is my pantry temperature. If the Q10 formula is correct and my pantry reaches upwards towards 90°, then the quality and nutrient value of of my canned and dried goods is greatly compromised. That's a problem we definitely need to address.

Sorry, I'm not very enthusiastic about most of your suggestions, :( but I do like the way you think. You're definitely a problem solver and that's an excellent thing!

Brenda, yes, that's definitely something I'm going to look into. One resource that describes how to make one out of a chest freezer is Prepper's Total Grid Failure Handbook. They made it sound very simple to do. I'll blog about anything else I learn.

Renee Nefe said...

I would try insulating the pantry more, cover up the windows and try to make it as cool in there as you can. Plant some trees outside of that room to block the sun from hitting it.
You might also want to consider digging a cellar.

Sparkless said...

I agree with insulating your pantry better and even considering new appliances because they are more energy efficient and old ones. A generator can work really well if you have power outages and want to keep your freezer going until the power is back up. You could also consider digging a cold storage room if you live in an area you can dig into the ground. My friends dug out an area in the side of a hill on their farm and made a cold storage room that kept their produce cold even in the heat of the summer. Good luck figuring out what will work for your particular home.

Leigh said...

Renee, we're talking about all those things, except plant more trees since we already have quite a few that shade the house. I think it's primarily poor insulation and single glazed windows plus the heat produced by the two appliances. That would be faster than digging a root cellar, but both are good possibilities.

Sparkless, good to hear from you! Dan's a generator guy, especially since batteries have such a short lifespan. So that's one of the things on the list. The other is a root cellar, although figuring out where to put it is a challenge considering the layout around the house and not having a nearby hill to dig into! Still, earth cooling would be by far the easiest way to go.

arta said...

Hi Leigh,
I don't know how our temperatures compare to yours. We live in South Africa on a farm, far NorthWest corner of the country on the edge of the Namib desert. It gets quite hot. We built a strawbale house and that insulates our home really well. Summer temperatures is about 45-50 Celsius during the day and winter a balmy 15-20 Celsius. The strawbales help a lot with insulation and we're installing an extraction fan right above the freezer and fridge this summer.....they do create a lot of heat. We already have one above the stove and cool the house with a small evaporative cooler unit. Our fridge is a new Defy 210liter and it has a good energy grading. We've used it for about 5 years now without any complaints although I would have liked if they came out with more baskets for the top :) That would make your 'often used' items easily reachable and would preserve the cold inside even more.
I really like what you're doing. Going offgrid or semi-offgrid is a daunting challenge, but it is so rewarding. It does mean you have to make a lifestyle change (like no hairdryers in my case), but it is so rewarding when you make it work.
We have 4 260Ah batteries, a 3kw inverter and 8 panels (240W to 300W). We only had 3 panels when we started out and that was more than enough to run the house, we added the extra panels when we needed more power for the dishwasher, the washing machine and the small aircon in summer. We currently run the entire house with our 8 panels as well as a couple of luxuries (dishwasher). Both my husband and I are in IT, so the laptops (3) are also thrown into the mix.
As for insulating your pantry, I think that is a great idea. Have you ever looked at aircrete? We're restoring a 1900 old house on the farm and are going to insulate it on the outside with aircrete 'tiles'. About 2 inch thick and we're going to stick them on the walls like tiles. That will prevent the outside heat from getting to the walls and then inside the house. The aircrete has bubbles which is an excellent insulator, but I know in the USA you have other better products that will work really well too. Aircrete you can make yourself though :)

CityCreekCountryRoad said...

Hello Leigh,

I follow your blog very informative and thoughtful.

I live at the edge of a large east coast city. Your urban/suburban readers might want to look at "Nana Pinches her Pennies" blog. She grew up like the Waltons but now lives in a city in the south. Her current post is writing about living with only a freezer, no fridge so it was interesting to compare the two blogs. I had great aunts who lived without a frig in my city and unlike us, they had no back yard.

City creek Country road

Farmerjohn said...

One thing that is easily overlooked but an important prt if your pantry temperature is the heat generation from the appliance motor and compressor. For that reason I removed them from the pantry and have them in the basement. The dry goods in the pantry now have an improved shelf life with the cooler air temp.

Farmerjohn said...

Oh-don’t forget that your solar system would still qualify for a tax credit even thought is a homemade system. It’s not as much as a few years ago but every dime counts.

Leigh said...

Arta, I can tell you how our temps compare, yours are hotter! Yikes, I thought our climate was hard for homesteading. I assume you don't get much rain, either. I understand why you built a straw bale house. Excellent choice. I often wish we'd started more from scratch than buying an old fixer-upper. It's been fun in some ways, but difficult to retrofit for the lifestyle we want to live, at least on our budget.

Thank you for the details on your system. It' so much more helpful to know how real people are using solar than what a sales company describes.

I've been looking into chest refrigerators or dual freezer/refrigerators but coming up with nothing. Seems that hasn't crossed the American manufacturer mindset. The closest I've found are plug in travel coolers (of which Dan already has several).

Thanks for the mention of Aircrete too. Dan's already started looking into it.

City Creek Country Road, thank you for the recommendation! Seems very timely, doesn't it?

Farmer John, that's exactly part of our problem! The pantry fridge and freezer produce too much heat. In fact, we've been discussing moving them to the back porch (because we have neither basement nor garage.

I didn't realize we could get a tax credit without going full grid-tied. Maybe that's just the rebate? Will definitely look into that, thanks!

Ann said...

I have been following your "pantry series" with interest. You have already received much better advice than I can really offer, but from what you've written I take it you don't have a basement? We have all our freezers and food storage down there and it stays really cool. Don't forget that if you can insulate your pantry your appliances will actually run less and generate less heat of their own.

Quinn said...

I haven't canned in a long time, but I freeze a lot, and like you, I have to hope we don't lose power for more than 2 or 3 days. I have a tiny "dorm fridge" and a small chest freezer. I could use more fridge area but this one sits on a heavy metal cabinet so it's at a comfortable height. A normal fridge - even a small one - would require a lot of leaning down and reaching in, which is very bad for my back. It's why I did without a kitchen stove for 20-odd years, until I could afford to have a wall oven put in. Anyway, the size of both fridge and freezer force me to plan carefully and try not to let anything be forgotten and go to waste - I get so mad at myself when I waste even a little food! My little system has been working fine for years, but right now, for the first time ever, the freezer is full of meat - far more than I expected to have - and I either need to get busy and figure out how to sell some (it is USDA processed/stamped for sale) or else plan on canning or drying ALL the vegetables from the garden this year, and also forget about my usual cider stock-up in November! I guess I needed to shake up my system a little bit...was getting set in my ways.

Toirdhealbheach Beucail said...

One problem we (and I think you) have to contend with is humidity as well as heat. Back home, we could sun-dry certain things will only protection from insects. Here, it will not work at all.

Leigh said...

Ann, no, no basement, but oh how we both wish we did. A basement was on our "dream farm" list when we first started looking at properties, but few places here have them. Dan would have like a garage second, but we got a carport and a couple of old outbuildings, so we've made due.

Quinn, we're always trying to fine tune! I think that's a good thing and find that questions or concerns motivate us to do better. Storage space is always a big one on our end too. You could can some of that meat. I find canned meat very handy for a quick meal.

TB, yes, we do have a bad problem with humidity. Like you, I've learned that there are many things I can't sun dry. Greens and herbs do okay, but any sliced or diced fruit or vegetable will mold before it dries. Forces me to use my electric dehydrator! The humidity is one of the reasons I got away from dehydrating for awhile. Now that I can vacuum seal the results in canning jars, I'm doing more of it.

Ed said...

Have you looked at propane refrigerators and freezers? That is what the local Amish (who are without electricity their entire lives) use.

squire said...

Supply enough energy for your freezer only. Keep several frozen gallons of water in the freezer and swap on half of them to your fridge each day.

Farmerjohn said...

Many states offer some sort of rebate and they each have different requirements. Then there is the federal tax credit. It covers grid tied and off grid and all monies spent on the project count. In
My case the state rebate and federal credit covered nearly 50 percent of my system. Before you spend another penny be sure and get the details. You might be able to do more than you think if you calculate the math first. I hope you are pleasantly surprised!

Leigh said...

Ed, I did look at them briefly, but they're pretty pricey and I'd still have to buy the propane. Right now I'm leaning toward a small chest fridge.

Squire, hmm. Dan and I talked about making an old-fashioned ice box. Your idea is certainly worth experimenting with.

Farmerjohn, thank you! I will indeed look into it. Considering our limited budget, every penny would help!

Retired Knitter said...

Wow, such an interesting blog post. Obviously living in a condo ... my life style is WAY different than yours. And I can never live "off grid" living here. But I do want to be more frugal about my impact on my carbon foot print and my pocket book. So I am careful about what I use - but I use all the current appliances.

I followed a blog once where the woman was focused on frugal living. She had a fridge the size of a college dorm style. When it died, she didn't want to replace it and did some extensive research on how to live without refrigeration. And I believe she did it for a period of time successfully,until she moved. But she wasn't trying to save food and seed for the off seasons. She wasn't trying to be off grid either. Just use less. She no longer blogs sadly. I enjoyed her frugal efforts. Inspired me.

Great post and great responses..

Renee Nefe said...

A lot of cellars out west are actually up instead of down. They would mound up thick walls of dirt and make a hill cellar. perhaps they were converted sod homes?

Nancy In Boise said...

Mother Earth News had great ideas about preserving fresh eggs. I wasn't sure if you already have a root cellar? If you don't if you thought about putting one in? I would do that if I had the space. There are propane fridges/freezers and models used in tropical climates as well. Maybe check Lehman's, they might have more ideas... unless you already have.

Nancy In Boise said...

I just saw something on Clay refrigerators to that might be something to look into? But I don't know how much they cost

Leigh said...

RT, getting a peek into different lifestyles is half the fun of the internet. I follow homestead bloggers all over the world and am always fascinated by their challenges and solutions. I learn quite a lot! I would have been very interested in the blog you mention. City Creek Country Road (above) mentions "Nana Pinches her Pennies." I looked up that blog and found an interesting woman who has no fridge, only a freezer. It's amazing how creative people get when put to it.

Renee, that's an option, maybe if we made it of straw bales. I can't imagine the insulation we'd need. If my house is as warm as it is with conventional insulation, what would it take to keep a structure at root cellar temperatures!

Nancy, eggs I've got down. In fact, all my experimenting enabled me to write How To Preserve Eggs :). No, we don't have a root cellar, but it's definitely on the list of possibilities and would be a great way to store the majority of the items in my fridge that don't really need to be there.

I looked at Lehman's awhile back and found they have gas refrigerators (natural and LP), but they're expensive. I hadn't heard of clay refrigerators and had to look those up. Reminds me of zeer pots. I experimented with a zeer pot when I was researching for Prepper's Livestock Handbook, but my humidity was too high so I didn't get good evaporation and hence no cooling.

Renee Nefe said...

maybe with straw bails and dirt? probably needs some research.

Leigh said...

Renee, that's one of the things I've been looking into. We've got some ideas and Dan's very enthusiastic about the project. :)