Upcycled Solar Food Dehydrator from a Used Vehicle

Reader Contribution by Holly Chiantaretto and Hallow Springs Farm
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Preserving your garden harvest is crucial to being able to reap the maximum benefits of your hard work. If you can some of your produce you will fully well know that there is a point when you will become exhausted with it and throw in the towel or run out of shelf space. Freezing food also has space limitations. Drying some of your produce is an excellent way to have access to your full harvest all winter long.

Commercial food dehydrators are wonderful if you are drying a very small amount of food. However, the amount of energy it takes is not worth the expense if you are drying a lot of produce or if you are on a limited amount of energy usage.

I had avoided drying my produce because of energy-usage issues, as we are in the process of transitioning to solar energy. So I sought out some groups in the area that were teaching about solar dehydration and making your own solar dehydrator. We helped to build one so we could really understand how it worked and be able to build one for ourselves. Then life happened.

Between all of the other projects on the farm, my job, and the kids, we put the fancy dehydrator low on the priority list. Buried under a sea of farm projects and my herb garden growing much more effectively than I had anticipated, I had to come up with a way to dehydrate.

Troubleshooting Food Dehydration

Herbs are tricky — they must be dried at a low temperature to retain their properties and will mold if they are dried too slowly. I tried hanging them in my porch kitchen and they molded, because our farm is in a hollow. So I began to have conversations with the veteran farmers in our area.

Our senior generation is often an untapped resource. I was told over and over, “We dried our maters in the back window of the old Buick.” I don’t have a beautiful classic car with a huge back window; but, I do have a broken down eyesore of a Jeep behind the barn and some old screens in the loft.

Some people like to keep everything and some people hate the thought of having something that is not being used. I am the latter and my husband is the former so this Jeep and the truck next to it, that I had been told are “jewels,” have been on my radar for things that need to go. But after all the wisdom I had acquired from our more experienced farmers, I began to see some value in those heaps of metal.

We have a minimal landfill waste system on our farm, roughly one garbage bag per year at the most goes to the landfill. Upcycling is the first step in disposing of our garbage in a responsible manner. Sending waste to be recycled is good. However, when it leaves your hands, it is hard to say how well it’s used and how much of it ends up in the landfill anyway. Knowing this makes you look at “junk” in a whole new way.

Components of a Solar Dehydrator

An old vehicle has all the elements of a successful food dehydrator. There are likely an infinite amount of ways to dehydrate food by upcycling something old. They just need to have the following elements:

An enclosed space to keep bugs from laying their eggs in your food while it’s drying.

Airflow so the moisture can be carried away. Car and truck bodies all have airflow.

Windows or plexiglass to allow light in and trap the heat. Tinted windows are the most beneficial to preserving the vitamins in your food. Some foods lose vitamin content when exposed to sunlight. Tinted windows eliminate that issue while still trapping heat.

A surface to lay out your produce that maximises the airflow around the food. I prop up an old screen on the top of the seats so there is airflow under and over the food, and the top of the vehicle is warmer.

Food Safety and Other Considerations

There are some issues with using a motor vehicle to dehydrate food. It has plastic in it. If you have read any information about the danger of plastics you will likely understand that plastic can give off fumes. That is the reason I would never dehydrate food in a newer vehicle. The risks of fumes emitting from plastic that is old is greatly reduced. That “new car smell” is likely toxic.

Of course, I do not hold a degree in chemistry or plastics, but I do err on the safe side as often as possible. Be sure the vehicle you are using is not only older but also is clean and has no toxic chemicals being stored in it, like motor oil or antifreeze. Whatever you would not put in your refrigerator is also what you should not have around your dehydrating food. This is what your grandmother would call “good common sense.”

Some of your dried foods will take longer than others. Things that have low water content like herbs need only two to three sunny days to dry. Produce that has higher water content can take longer. It is better to have your produce too dry. If you pull it and put it into jars when there is still water present they will mold and waste all your hard work.

I have enjoyed this method of dehydrating food so much that next year, I intend on converting two old truck cabs into permanent dehydrators by stripping the inside and building shelves in them.

Really the best way to find out what works is to be adventurous in your experiments. Don’t be afraid to fail at an idea the first several times. The process of innovation in food production will feed your mind and your stomach.

Holly Chiantarettois an organic farmer and goat breeder in Kentucky where she also raises cattle, pigs, and chickens and preserves the harvests from her garden. Connect with Holly atHallow Springs Farmand onFacebook.

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