Principle

The greenhouse effect in the solar collector works not only for the better heat insulation of the solar collector, but also for its protection from the external influences of the weather. The heating is not significantly influenced by the plexiglass disc, but the collector clearly cools down slower. Therefore, the disc has also the function that - in case of clouds - the water does not cool so strongly down in the solar collector, thus losses are minimized.

The disk helps to slow down the cooling process in case that ambient conditions change (clouds) it keeps the temperature of the water, thus minimising losses.

Benefits

• Experiment is part of a complete solution set with a total of 17 experiments for Renewable Energy Basics and Heat energy
• Safe experimentation: the lamp is protected against touch, the housing is well ventilated with the aid of holes and is only slightly heated
• Stable setup by using the optical bench

Tasks

1. How can the greenhouse effect be used?
2. In these experiments, the effects of a plexiglass disc fixed at the solar collector, are to be observed and compared to the solar collector without disc. For this purpose the temperature gradation of the absorber plates (of the solar collector) will be examined with and without plexiglass disc during the heating up and the subsequent cooling.

Learning objectives

• Greenhouse effect
• Solar collector
• Heat insulation