Act: Inspiration

Solar Dehydrator: A Very Appropriate Technology

December 17, 2019

Some of our modern tech is inappropriate. Rude. Too gaseous for the air, too messy for the planet.

But some technologies are easy on the Earth by nature, leveraging the existing energy flows that surround us. Personally, it’s the hand tools, the solar tools and the things that work all by themselves that bring the most value to my life. There’s no substitute for a mattock and a couple of good shovels, which leverage human effort into great effects with a negligible environmental impact. I love the wood stove, the solar shower, the solar oven, the laundry rack, the ceiling fans and most especially, my new solar dehydrator.

The best tool isn’t one that just promises to make a job easier or faster, it’s one that makes a job possible, where before it was impossible. It’s so humid here even in drought conditions that I have a terrible time getting my home-grown hibiscus tea, hops and corn dry enough so they won’t mold in storage. The solar oven works too well for dehydration; it just cooks stuff. How on earth was I going to dry apple rings or tomatoes?

I could get an electric dehydrator for a hundred bucks, pay to run it, and then pay for extra AC to cool the house back down. No thanks.

It turns out, two of my homeschooling/homesteading friends were having similar thoughts. We got together with these free plans from Appalachian State and made our dehydration dreams a reality. Working together is wonderful partly because it’s fun, partly because teenagers provide built-in babysitting, and partly because you can pool your extras.

The plans specify about $300 worth of materials, but I think we spent about $200 total to build three dehydrators. Somebody had some plywood and hinges lying around. Somebody else had extra chicken wire that could sub for the specialty metal in the heat collector. Somebody found some close-enough-sized windows at the ReStore for $6, instead of ordering new plastic. My neighbor gave me exterior paint in return for tractor work.

Home-made solar dehydrator

My home-made solar dehydrator incorporates lots of salvaged materials: metal roofing off the old farm house we took down, cheap windows from the ReStore, reclaimed lumber and some paint that was sitting in my neighbor’s basement

After some trial and error, I’m pleased with how the dehydrator functions. I still didn’t get many dried tomatoes, because it never rained again after our June flood so the plants yielded poorly. I did some excellent tests on fruit from the local orchard, though, and lots of herbs and hibiscus and hard corn. Then I learned my beloved green bean can be eaten as dry beans, if only they can be dried enough to pulverize the husks and get the beans out. Impossible without the dehydrator. With it, totally possible. It’s a huge step forward in my family’s journey to eat more ecologically.

Inside a home-made solar dehydrator

Drying roselle for hibiscus tea and chili peppers for warm spicy winter meals. Note the screen above the trays that lets warm air through the dehydrator. That screen was leftover from the soffit screens on our house.

It’s easy, when I’m excited about a favorite new tool, to think I should get all the tools. After all, the more gadgets I have the easier my life will be, right? If I outsource every bothersome chore to a machine, I’ll have nothing to do but sit on the couch and eat bonbons.

Let’s forget for a moment that this is a recipe for a very unhealthy body, and pretend that I have no greater ambition than snarfing down improbable ice cream. Does it really save time to own a dryer, a dishwasher, a Roomba and all the other robot slaves? I have to earn money to buy these machines, then work more for the electricity to run them, then even more to repair or replace them. At what point does that take longer than doing the chore myself?

MIT graduate Eric Brende set out to answer this question by living among people much like the Mennonites, with their horses and buggies, their aversion to buttons. The result is a fascinating chronicle called Better Off: Flipping the Switch on Technology. It’s a funny, illuminating look at a different kind of living.

Spoiler alert: after his experiment, Brende concluded most of us moderns are working harder than we have to, in order to support our machine collection. What’s more, the Mennonites are working too hard for their tech! They cut hay for their horses, which is a lot of work, and while the horses also plow and provide transport, the main activity they’re needed for is… wait for it… cutting hay. It would be faster and easier just to walk, and cut a little hay by hand for the milk cow.

I feel this way about the dish washer. There are only four of us, and I wash dishes twice a day by hand, which takes about ten minutes. My hand technique uses about two gallons of water, drawn off the wood stove in the winter, lukewarm from the tap in the summer, so there’s little or no electricity involved. When I had a dish washer, I would rinse by hand because we don’t fill a load every meal and even a good dishwasher did not perform as advertised on dried-on food. Then load the washer, listen to it rattle on forever, unload it, sort out the things that didn’t quite get clean, wash them again, etc.

Instead of twenty minutes a day it took at least thirty, involved extra bending over, and expanded from a quick over-and-done task into an all-day affair. Dish washers cost hundreds of dollars to buy, need electricity to run, and break down early due to planned obsolescence. Now, I certainly don’t begrudge a person their dishwasher if they’ve got carpal tunnel or fifteen people in their house. In those and other cases, you need what you need, and if you fill a load at every meal it may even be more efficient. But I propose that for most of us, dish washers actually take more time and energy than hand washing just to do the dishes, before you even add up the work at a 9-5 to pay for the thing.

The critique of hand washing is everywhere, and everywhere it looks to me to be poorly reasoned, and tested badly or not at all. It’s definitely true that bad hand technique uses more hot water than a modern efficient dish washer. However, some of the studies I read that supported the environmental efficiency of machines over hands had serious bias baked into the experiments. Some credited only the energy used to run the machine, ignoring the energy and materials used to make it (“embodied energy”). Some compared the very best machines with silly people who leave the hot water running all the time while they wash. This is a case of not just reading and following the advice, but making sure the advice is true in your situation before you act on it.

(Incidentally, if you’re worried you’ll get sick from hand-washed dishes, you should know that kids who live in hand-wash houses get less asthma and eczema, and no extra food-borne illness.)

Other large appliances can also be counterproductive. When I traveled around New Zealand getting farming experience, I stayed in thirteen different houses with families of all shapes and sizes. Only one of those houses had a television, a microwave and a dryer. Some of them had none of these things, and they were no less comfortable to me. Shipping to that island nation is expensive, so the big electronics cost a little more. People think harder before they buy one. Then again, our electronics cost more too if they’re put on a credit card and paid back with interest. Why don’t we think harder?

My family has thought hard about which machines we really want to pay to buy, pay to feed, and pay the ecological consequences of owning. We’ve definitely got more tools than the Mennonites, including a chainsaw and an elderly tractor, and we know we’re working harder for the luxury of having them. But at least we’ve carefully considered each one.

Will this machine make our life better? Often the answer is: nope. So we don’t buy it. If we already have it, we try to find someone who genuinely needs it, or if it’s at the end of its life, dispose of it properly. Make no mistake, not buying it in the first place is by far the most Earth-friendly option, because it doesn’t drive new production of ever more stuff.

Food dehydrated in a home-made solar dehydrator

Home-grown dehydrated blue dent corn, black cowpeas and roselle hibiscus for tea. Apple slices from our local orchard. None of it’s going to get moldy.

Around here there’s no electric refrigerator, no clothes dryer, no electric stove or oven, no television or cable or household internet. No coffee pot, no microwave, no Keureg, no stand mixer, no HVAC system or central heating and cooling. I find my little hand-made house more comfortable than all my previous residences. Of course we still heat our food and our home; we just have lower-tech ways of doing it, which has lowered our electricity usage by 85%.

You’re not me. You might be a neat freak with toddlers, in which case the Roomba is a matter of mental health. If so, I salute you for figuring out what you need to be sane. You might need the leaf blower because with only the one arm, there’s no other way to shovel the deck. I understand. But does every machine in your house make your life better? I bet there’s at least one that could go to someone who might actually need it, and stop eating your time, space and energy.

I think that’s the first step toward genuinely appropriate technology: admit that every electric or gas tool is a time suck as well as a time saver, and some of them suck more than they save, even though the advertising boasted otherwise. Then, think through how you really use your tech and how you might change your habits for the better. No need to get rid of potential freeloaders completely at first; just unplug or box them up for a while, and get more creative at meeting your needs.

Some of our modern tech is appropriate, and some of it just isn’t. Private jets have recently come under fire as contributing nothing meaningful to the advancement of the human race, while damaging our climate. Then again, the way the tech is used may be the problem, rather than the tech itself. That trip to New Zealand was great for my personal growth, but I can’t say the same about every flight I’ve ever taken.

Reimagining our relationship to the tools that serve us is essential, if we want to continue as a species on this planet. Do you have a favorite low-power or electricity-free tool that makes your life easier? What do you thrive without, that everyone else seems to have? How do you meet that need differently? Better yet, run a little experiment and stop using some machine you think you need, then tell us how it went. I’m going to quit the vacuum since it’s dying anyway, in favor of the hand-powered carpet sweeper that’s been languishing unused in the cupboard.

Kara Stiff

Kara Stiff

I have a BS in Sustainable Agriculture from the University of Maine, and I worked on sustainability issues in Native Alaskan communities through Cooperative Extension before moving to North Carolina. My goal with my writing and in my life is to inspire others to think critically about their choices in order to build communities that are happier, healthier and gentler on the planet.

Tags: appropriate technology, building resilient communities, Building resilient food and farming systems, powering down