What Are the Different Types of Solar Hot Water Systems?
There are 2 types of collectors you can choose from:
Flat panel solar collectors
Flat plate solar hot water collectors are ideal for those on a budget and in areas that are not affected by frost. These systems work on copper pipes running through a glass covered collector, sometimes connected to a water storage tank on the roof, though usually the storage tank is on the ground. The sun heats the copper pipes and the resulting hot water is fed back to the storage tank.
Evacuated tube solar collectors
This type of solar hot water system is higher efficiency and better suited to frost-prone areas, as they don’t crack when the temperature drops below freezing.
Evacuated tube systems can extract the heat out of the air on a humid day and don’t need direct sunlight. The total efficiency is higher and they perform better than flat panel systems when the sun is not directly on the collectors. eg. early in the morning or in the late afternoon. As well as being more efficient, they’re also more durable and cheaper to repair.
Evacuated tube solar hot water systems consists of two glass tubes that are fused at the top and bottom. The space between the two tubes is evacuated to form a vacuum. A copper pipe running through the centre of the tube meets a common manifold that is then connected to a slow flow circulation pump that pumps water to a storage tank below. This heats the water during the day. Because the tank is so well insulated, the water stays hot for a number of days.
With both types of systems, the sun generally provides sufficient heat to give you plenty of hot water for most of the year, but when there are a number of cold days, your system will need a helping hand (most likely in winter). This is where your electric or gas booster comes in. This heats the water when there’s not quite enough heat in the sun to do the job.