Using a Vehicle to Solar Dehydrate Peppers and Tomatoes

Can a vehicle be used to solar dehydrate peppers and tomatoes?

Saw this on an episode of Doomsday preppers, or something like that, so I decided to give it a try. A tray off of an electric dehydrator was used to hold the food, and a meat thermometer was used to measure the air temperature. Two of the windows of the SUV were cracked around 1/8 – 3/16 inch.

The goal is to capture the greenhouse effect of the summer sun on the vehicle. Then use the collected heat from the greenhouse effect to dehydrate peppers and tomatoes.

Types of peppers in this experiment:

Preparing the Peppers

All three types of peppers were picked fresh from the garden just minutes before the experiment.  Peppers were cut up, placed on the tray along with the tomatoes, then put inside the car.

The tomatoes were sliced around 1/4 inch thick and had a light coat of salt put on them.  The salt seemed reasonable considering how much moisture is inside tomatoes.

Solar Dehydration Results

The first day the car was facing north / south.  It took several hours for the greenhouse effect to bring temperatures above 120 degrees, which is the lowest temperature on the meat thermometer.

At the end of the first day the Tabasco peppers were dried, but the bell and jalapeno were not.

Second day the SUV was turned east / west early in the morning. This seemed to maximize the sun. Facing east / west, the inside of the car got hotter faster than north / south, and stayed hotter longer than north / south.

On average, the temperature inside the SUV was 30 degrees hotter than outside. While playing around a month ago, the thermometer was placed on the dash of the SUV. Temperature on the dash reached 170 degrees.

Peppers were left in the car for three day.

At the end of the third day:

  • Bell peppers had drastically reduced in size.
  • Jalapeno peppers felt oily.
  • Tabasco peppers dried the fastest and had the least shrinkage.

I have been playing around with this for a couple of months before the video was made. Onions dried well, but not as good as the Tabasco peppers.


In conclusion, I suspect the jalapeno peppers have some kind of oil in them, which is why they did not fully dehydrate.

Bell peppers had a lot of water in them, so they shrunk the most.  Due to the results, I feel bell peppers are poor candidates for dehydration.  They are probably better suited for making hot sauce and canning than dehydration.

Tomatoes did well.  Maybe slicing them thinner would have yielded better results?

Tabasco peppers had perfect results.  After just one day in the vehicle, the Tabasco peppers were fully dried and ready to be ground into pepper flakes.