In short, solar chest freezers and refrigerators work by absorbing sunlight and converting it into energy. This energy is then used to cool the storage compartment the device contains. There are no moving parts and no electricity at all; the whole process is based on natural sunlight.
Standard refrigerators and freezers, like what most people have in their kitchen, garage, basement, or RV, are equipped with motors that compress a refrigeration solution to cool the interior of the appliance.
On the other hand, solar refrigerators and freezers are absorption devices. In other words, they harness the heat from the sun and use the thermal energy to convert the cooling solution into a liquid.
As a result, energy is generated, and as a result, the appliance is able to maintain low temperatures in refrigerators and freezers, thereby maintaining the contents stored therein.
The first solar-powered refrigerator and freezer use both sunlight and photovoltaic cells to charge lithium-ion batteries. In the absence of sunlight, the battery can stay charged long enough to power the device for several hours.
Today, however, thanks to technological advancements, solar-powered refrigerators and freezers no longer use batteries. Conversely, the transition of the refrigerant from a gaseous state to a liquid state generates enough thermal energy to keep the temperature inside the appliance cool in the absence of sunlight.
Therefore, no batteries are needed to power the solar refrigerator at night, on cloudy days, indoors, or in any other environment without sunlight.
After you buy a solar refrigerator, you don't need to spend a cent to run it. Solar panels collect energy from the sun and convert that energy into electricity that is used to keep devices cool. It is one of the most environmentally friendly products worth having.