The type of solar cooker used by us

After a series of tests the Dierkx type, with the slanting lid, proved to be one of the best. The slanting lid causes some natural phenomena: air current and radiation.

In the cooker a current of hot, humid air develops, which quickens the cooking process. This current is due to the 2 spoonfuls of water to be put into the pre-heated cooker together with the pans. The pans are on a grate so that the hot air heats the bottom of the pans as well. This implies, however, that the oven must be steam-tight. In a pre-heated cooker the temperature is about 150 C. After the food has been put in, the temperature is about 115 C. The pressure gets a little higher and the food in the pans is steamed ready.

At the front the bottom of the solar cooker is a little deeper. Here the spoonfuls of water turn into steam. As this steam rises, due to the slanting lid, it pushes the other air away and thus the circulation starts. From the steam drops condense against the cold pans. These drops roll to the front and vaporize again. This is also the case because at the front there is a slanting part where no heat is extracted by the pans, but it does catch the sunrays from the reflecting screen.

If the cooker has been made according to the drawing, the lid will be curved down a little, so that the sunrays will not hit the sides of the windowpane too much. Every half hour the standard cooker has to be turned a little, with the turning of the sun. With wider cookers, easily to be constructed of inner boxes from the folding device, the turning can wait a little longer.

Programming the cooker requires some experience of the user. According to its developer, Mr Dierkx, you can decide beforehand when the food must be ready (give or take a quarter of an hour). This can be done by putting cooker and reflecting screen in a certain position. About 1 hours before the time the food should be ready, the sunrays must be fully caught. When people would like to eat just before dark, the cooker can be used to keep the food hot. When the reflecting screen is laid flat, it reflects the heat. The rest of the cooker is insulated well enough to hold the heat.