Chances are you've heard of solar ovens, but the whole concept is pretty complicated, right? "Actually, it's pretty foolproof," Jonathan says, opening the Plexiglas door on his solar oven and pulling out a quiche. "It's an oven, it gets hot," he laughs. The quiche looks good: puffy and evenly browned across the top. "It's a moist heat, so you can bake just about anything except crusty breads," says Julie. And because it's a moist heat, it's pretty much impossible to burn or overcook your food—just keep an eye on the thermometer to make sure things are hot enough.
Solar cooking is nothing new. The first documented efforts were made by a Swiss naturalist named Horace de Saussure in the 16th century. But only recently has it been developed into something that actually makes sense on a day-to-day (at least in the summer) level. De Saussure's oven, for example, only heated to about 190 degrees—not enough to cook anything seriously. Krausert's main oven—a commercially produced appliance called Sun Oven— can get up to 400 degrees at noon (when the sun is at its most direct angle).
The Sun Oven will set you back $300 or more (although Jonathan says he couldn't build a replica for that price, so it might be worth it if you've got the dough), but a simpler version can be made at home. Jonathan, for example, has a cardboard-and-Plexiglas model he whipped up in about 20 minutes. That little box will get up to only about 200 degrees, but that's enough to cook some things if you've got the time. Raw pork sausage, for example, should be cooked to an internal temperature of 170 degrees to be safe. Jonathan's little cardboard oven could safely cook one of his favorite solar oven dishes: sausage and sauerkraut.
Solar dehydration is even easier. Jonathan and Julie have a large solar dehydrator, basically a vented box with a tempered glass top and screen shelves inside, which Jonathan built after using a commercial electric dehydrator that someone gave him as a gift. "It was like running a hair dryer for two days," he says. That's a lot of electricity for a few ounces of raisins. His homemade dehydrator, on the other hand, will dry 20 pounds of grapes in about a day and a half. Plus, he built a channel along the bottom of the glass lid that collects condensed water, so in a pinch it could be used as a still. "You could put water from the ditch into this thing, and drink what comes out," Jonathan says.
He's also got experiments going with a couple of other models of solar ovens and dehydrators. One uses an old satellite TV dish, painted silver. It works, but he has plans for improvement. It's a relatively new field of ecological experimentation.
This summer, get out of the kitchen and onto the patio—cook up a casserole with nothing but the power of the sun!
Jonathan and Julie will be teaching a class on solar cooking and dehydrating this month. Register on Wasatch Community Garden's website to learn the ins and outs of cooking with the sun.
Solar Cooking, Sat. July 16, 11am-1pm. Fairpark Garden, 1037 W 300 N. http://wasatchgardens.org