How Does the Solar Thermal Trolley Work?

The solar trolley works by absorbing solar radiation from the sun and transfering this energy in to water the form of heat. Water is pumped through a coiled pipe inside the collector and into another coiled pipe inside the heat exchanger. These two coils from a closed loop in which the same water circulates continuously. As the water passes through the collector coil it is heated by the sun's solar energy. When this hot water passes through the heat exchanger coil some of its heat energy is transferred to the water in the heat exchanger vessel. Gradually, the water in the heat exchanger vessel is heated to the desired level, at which point the water pump switches off.
Illustration on how the trolley works