It is a fantastic thought to put food in a solar cooker at night, point it to the heavens, and it will cool. There is something beautiful about this. Perhaps it is the ‘of course’ moment you have when the basic physics dawns, i.e. everything radiates heat (except a blackhole?). If you direct as much of that away from itself and stop any coming in, that body will cool. And we’re not just talking a wee chill here, according to one solar oven inventor who appears to be a physics professor, we are talking a 10C difference between contents and ambient temperature, astonishing. Maybe with the passing of Venus, I, and indeed the family, are just caught up in the wonders of all things cosmic this week.
Well, being housebound with an infected and inflamed knee led to significant boredom, and therefore the construction of a solar oven, obviously.
There are a lot of designs, but I made a box oven as shown from this now ancient link. A fine use for left over bike boxes. There is a most elegant way of achieving an angle of 67 to achieve the necessary reflection into your black box, please read. No protractor, and no iPhone.
We modified the original by utilising the insulating power of an Esky, which would be lunacy (i.e. it would melt) if you didn’t line it with plenty of cardboard. A bit of glass we picked up from the recycling dump over the top and away we go. It got to 140C when I decided to wipe the surface with a damp cloth. Well, the glass looked toughened, but moments later a wonderful curved pattern of fractures appeared. Doh.
Once we did get our piece of ordered glass, in went the first dish. I had a turkey leg which needed using. There are very few recipes for turkey leg. HughFW recommends cooking as Coq au Vin, and Alastair Little has one stuffed in the Umbrian style- apparently those Umbrians use it a lot, particularly in place of veal.
In the end I went for a Chinese recipe (no recipes in Ken Hom or Kenneth Lo). Well, a Chinese ‘concept’, no recipe.
- 1 turkey leg (with thigh)
- A big Slug of soy sauce
- chunk of ginger
- half an onion
- a carrot
- 2 spokes of star anise
I think this went in at 10ish, at a significant angle as even the winter sun here will have a 30deg incidence at midday. The boys loved it and even more bizarrely, Rory loved fresh cloud ear fungus cooked with bok choi and the stock from the turkey. Odd, since he usually won’t touch a ‘room.
Note to self- buy turkey chicks to fatten for Christmas.
Now, we’ve had a few problem with our glass. It keeps breaking. Bizarre curvy fracture pattern result, toughened or not. And since turkeyville, we’ve broken two more bits.
Anyway, I have made a version of the superbly simply, no, mindblowingly brilliant windshield funnel shown below from the solarcooking.org website. By curious coincidence, it hails from Oaxaca, Mexico, home of one of the finest dishes known to man, the Oaxacan Mole.
We’ve just got some roasting bags this week, so presuming they don’t frigging melt, here goes…..