Passive solar heating is mainly collecting the sun's energy without the use of machines. Usually a passive solar building has a window facing south to collect the energy. The rest of the house is made of stone or masonry, something that lets the collected heat out slowly. In passive solar cooling buildings, natural ventilation, such as thermal chimneys and wing walls, is used to cool the building. Active solar heating is solar heating using some sort of mechanical device. There are two types of systems, liquid and air systems, which each use either a pump or fan to distribute the warm air. Active solar cooling is done by turning the sun's radiation into electrical current and the used to run a cooler.
My question is, would a clear layer as thin as saran wrap actually keep more heat in a solar oven or does it need to be a thicker layer such as glass? I predicted that the saran wrap would have a noticeable effect on the temp. But not a drastic difference. To make my ovens I used; 2 boxes, packing peanuts, tape, saran wrap, a cooking thermometer, and tin foil. Having been in the sun for about thirty minutes there was a noticeable temperate difference in the boxes than when they were first put out. After 45 minutes the box with saran wrap was just barely warmer. Also you have to give room for error. But the control was definitely cooler than the 2nd box. I found that although a piece of glass would have been a more effective lid the idea of having the heat trapped was still evident.
