This heat retention solar oven works like a greenhouse, allowing sunlight to pass into the pyrex bowl while also retaining heat. Inside the bowl an absorption container filled with dark-colored rocks will act as a heat sink that absorbs sunlight and will heat food placed on top of it. The rocks soaked up heat during the day and then released it on demand. The container is an aluminium plate containing holes arranged in a circular array to allow air to pass through. There are only three contact points between the container and the bowl. The reflector foil reflects the light directly into the bottom of the container.
- Low Tech and Low Cost.This solar oven can easily heat up to about 50C to 100C degrees.
- The absorption container is inside of the bowl. Use alone or filled with rocks.
- Minimal contact surface between the container and the bowl.
- It keeps food hot until serving time.
- It can be moved temporarily indoors for its retained-heat cooking time.