Solar heating systems use radiation from the sun to heat water or air in a solar collector that can be mounted on the roof or on ground. From the collector, the heat is transferred directly to the interior space or to a storage system from which hot water or air is distributed into a building as required.
Liquid-Based And Air-Based Solar Heating Systems
Liquid-based solar heating systems heat water or heat-transfer liquid in a flat plate or evacuated tube collector. They are usually used to provide hot water in households. They are also of great use during the summer months when there is increased demand or usage of swimming pools, camper vans, and holiday rental homes.
Air-based systems also work with solar collectors, but they heat air instead of a liquid. Air absorbs and transfers solar energy and is usually used for space heating. A solar heating system can only contribute a small part of the heating energy requirements. The demand for warm air is highest during winter when the sun is weakest.
Both air and liquid solar heating systems can supplement forced air systems. A solar heating system that cannot provide adequate space heating has to be supported by an auxiliary or back-up system that provides the additional heat.
Financial Advantages of Solar Heating Systems
Solar heating systems are most economical when they are used year-round in climates with cold periods and high solar insolation rates. In the long-run they are more cost-effective than systems that require electricity, propane, and oil heat. Many states support solar heating installations and offer financial incentives such as tax exemptions or rebates.
The cost of an active solar heating system depends on various factors and can range from $30 to $80 per square foot of collector area. Usually, the larger the system, the cheaper per unit of collector area. Many US-citizens have decided to install a solar water heating system in their household as it offers a quick payback (7-15 years for an average household).
However, installing solar heating systems does require plumbing and heating expertise to size and balance the system effectively for efficient performance.