The problem with most solar ovens is that they’re flimsy builds that will stand up to only a handful of uses. But this one stands apart from that stereotype. It’s big, sturdy, and used a lot of math to efficiently gather the sun’s energy when cooking food.
This is the third version of the build and each has included many improvements. The obvious change here is a move from aluminum reflectors to actual mirror reflectors. These attach at a carefully calculated angle to get the most power from the rays they are redirecting. The orange mounting brackets for the mirrors also serve as a storage area for transport. The rectangular reflectors fit perfectly between them (stacked on top of the tempered glass that makes up the transparent side of the cooking chamber).
The body of the oven doesn’t track the sun and one of the future improvements mentions adding tilt functionality to the base. We’d suggest taking a look at some of the solar tracking setups used for PV arrays.
[Thanks John]
Solar ovens are cool and all, but how do you get over the fact that when I want a hot meal isn’t when the sun is out?
Obvious first world problem you have… Hungry people will eat not when its convenient, but when they can. Not to mention those who prefer to live within minimal means having to learn to live in some sacrifice to convenience.
If the sun ain’t out, the sun ain’t out – it don’t care if you live in a first world country or not.
Stick it an a haybox while the sun shines.
http://en.wikipedia.org/wiki/Haybox
And stick it in a sand pot when the sun don’t.
http://en.wikipedia.org/wiki/Pot-in-pot_refrigerator
There is a neat technology which stores the energy from photons in lignin and cellulose, basically a chemical fuel cell, and with flaming pyrolysis can release the energy stored from the photons when the sun is not out. Sulfation is not a problem, and it’s completely recyclable.
To burn the “wood”, as it is called, very efficiently, you can use a Winiarksi inspired rocket stove, or a central european inspired masonry heater a.k.a. kachelofen/tulikivi, or a gasifying wood gas burning stove, such as the Reed-Larsen woodgas stove.
He could just eat warm food at midday and the rest of the day “cold” food. I wouldn’t recommend burning wood over solar heating. Burning wood will – always – be less efficient. Plants are not efficient at turning solar energy into wood, during the burning you get a lot of filthy by-products and you also take nutritions from the soil by removing the wood.
Really? Last time I checked ash is a perfect nutrient source for plants.
Ash is highly alkali. For those of us that live in alkali deserts, ash is a terrible fertilizer and will destroy your soil’s ability to grow plants.
I’ve heard of this, what did you call it, “Woood”? Can’t it also be used as a building material? Sounds very intriguing, who invented it? Is there a patent?
I guess someone had to make that obligatory comment :)… Uh, fire? Homo-sapiens has figured out how to get fire to work for him ages ago.
I’m not going to be getting rid of the propane kitchen range anytime soon I hope, but good to know of other options if life throws one the proverbial curve ball. IMO solar thermal get too little press
With it being 100+ degrees in DC lately, I have been thinking about building one of these so I can still make bread and not feel guilty about running the air with the oven on. Anyone have any experience cooking with these? Also anyone ever hacked together a solar tumbler dryer?
A “solar dryer” is actually really simple to build: A length of rope stretched between two vertical surfaces.
It’s portable too!
There is a reason I said “tumbler dryer” a lot of homeowner associations don’t allow clothes lines. I have one inside, but if it is really humid outside (which it often is in DC) clothes will turn sour before they get dry.
“The problem with most solar ovens is that they’re flimsy builds that will stand up to only a handful of uses.”
Really? How many Solar Ovens have you built and used? The last one I built cost all of $7.- U.S. because I had to buy the glass and have it cut, but the rest was made from cardboard boxes and aluminum foil glued to the cardboard for reflectors, I had some old black tempra paint to coat the inside with and I used it every day for nearly a year.
It wasn’t “flimsy” in the least, but it wasn’t waterproof and I forgot outside it during a sudden downpour and it got so soggy that it collapsed.
I’d put my food in about 9 am and remove it by 3:30 pm and have delicious chicken, rice, artichokes, and more, every day.
Yes, even when it was overcast, it just took longer to cook the food that’s all.
Of course, it’s not practical for those who have regular working hours unless you take it to work, but nearly anyone else, it works great!
That’s a long time to leave your food in a bacteria friendly environment. There’s a reason sous-vide cookers are air tight sealed.
I sense that you have never used a solar cooker, any half decent one will get more than hot enough for food safety on even intermittent sun on a cloudy day.
Most often anytime I make a solar cooker the first thing that happens is I underestimate it and somehow burn myself.
The easiest one to make is the chair cooker – a roundish fold-up camping chair with two of the car windscreen reflector shields in it to make a “dish” and a dark pot inside an oven bag, sitting on a brick to raise it a bit. Will cook curries, stews, potatoes, rice no problems. Oven bag is the secret, to reduce convectional and wind losses.
I have a commercially made cooker with double glazing and perlite insulation, it brings to a hard boil 10 litres of water from the tap in 40 minutes or less on a sunny day even in winter. Pre heated it will roast a succulent chicken in less than two hours.