What is a method to measure the amount of energy a solar cooker device consumes and produces?

Question

I am thinking about using these blueprints for my cooker. http://mysite.mweb.co.za/residents/net02833/makebox.htm

Answer 1

For an estimate, search the web for the average solar insolation for your area for this time of year. From that, calculate the average energy arriving over your collection area each hour. For an actual measurement, line a small, closed glass container with felt, fill it with a carefully measured quantity of water, and measure its temperature increase. It will lose some heat to conduction, convection, and radiation, but it will absorb nearly all the energy landing on it.

To get the other measurement I think you want, build a second, identical unit but with no collectors or sunlight. Heat it electrically and measure how much power you need to apply to create conditions comparable to the solar unit (with identical food inside). That will give you the most meaningful comparison without complicated instrumentation.

Answer 2

If you placed an SS Oven Type Thermometer probe tip into the cooking area, you could determine the heat (temperature) within the Solar Oven.

My assumption is that being solar powered, its consumption of energy from the commercial mains and batteries is zero.

Given the cubic feet of the interior of the Oven,
and the ambient temperature; Use Oven Temp minus Ambient Temperature to determine temp rise due to Solar Heating. In Air Conditioning and Heating training manuals there is a formula for heat rise per cubic foot expressed as BTU requirements. You should be able to use that formula to get close to the energy produced by the Solar Collector.

Looked at your diagram for the cooker...yeah, it should work.
However, if you really want to do something neato...Get some shiney aluminum sheet stock and using wire, tie the ends of the sheet together so that the aluminum forms almost a "U" shape. Prop that reflector up in such a way the the Sun shines down onto the reflector and the reflector's reflected sunlight falls onto the aluminized box you showed in the drawings...Adjust the distance and position of the box until it gets the maximum heat. That should work much better.