Installing a solar water heater is one popular method for homeowners to reduce their electric bill. These systems use renewable energy to reduce the need for grid power while delivering high volumes of hot water.
Flat plate collectors work on copper pipes running through a glass covered collector, often connecting to a water storage tank on the roof. The sun heats the copper pipes and the resulting hot water is thermo-siphoned out of storage tank.
Evacuated tubes consist of two glass tubes fused at the top and bottom. The space between the two tubes is evacuated to form a vacuum. A copper pipe (called a heat pipe) running through the centre of the tube meets a common manifold. That then connects to a slow flow circulation pump that pumps water to a storage tank below, thus heating the water during the day. The hot water can be used at night or the next day due to the insulation of the tank.
Evacuation tube systems are superior as they can extract the heat out of the air on a humid day and don’t need direct sunlight. Due to the vacuum inside the glass tube, the total efficiency in all areas is higher. There’s also better performance when the sun is not at an optimum angle. This could include times such as when it’s early in the morning or in the late afternoon.
