Solar heating refers to any process in which sunlight is converted into renewable energy for the purpose of producing heat. Typically solar heating systems use solar collectors to heat water, and this water is then stored in a tank for a variety of purposes. Solar water heating systems have large-scale industrial applications (such as using heated/boiling water to spin turbines), but smaller-scale systems are also commonly found in domestic settings. In private homes, solar heating systems are used either as a heat source to heat the home itself, as a means of heating domestic hot water, or both. The technology and methods used to collect sunlight and heat water varies greatly from system to system, but almost all will include a water storage tank and some kind of solar collector to capture energy from the sun.
Solar water heating systems can be roughly split into two categories; passive and active.
- Passive solar water heating systems are very basic in design, collecting energy from the sun using little or no modern technology or moving parts. These systems are therefore usually quite cheap and require minimal maintenance, but are also much less efficient and less effective than active systems. Integrated collector storage (where the water tank has a glass top and is placed in direct sunlight) is an example of passive solar water heating.
- Active systems are more advanced and sophisticated, collecting sunlight with the help of modern technology. Active systems generally use at least one pump to circulate water or a coolant, meaning that the water tank and solar collectors can be placed in different parts of the home. This allows greater freedom when designing the heating system, allowing systems to be tailored to fit the building they are installed in. Although more expensive to install than passive systems, active solar water heating systems are a much more efficient way of heating water. A water storage tank heated by roof-mounted solar thermal panels is an example of an active solar water heating system.
SunPump and Solar Heating
While active solar water heating systems are highly efficient, most suffer from the same problem; when the sun goes down, the system stops collecting energy. Water storage tanks are well insulated and will store heated water for several hours, but eventually even the best systems will begin to cool. This has been a problem for the solar industry for decades, both for solar thermal panels, photovoltaic (PV) panels and especially for passive solar heating systems.
The SunPump is a hybrid solar water heating system, integrating a heat pump into its solar thermal panels. The heat pump collects energy directly from air outside the home, allowing the SunPump to collect energy at night as well as by day. Combined with high-efficiency solar thermal panels, this allows the SunPump to operate as a home’s primary heat source, meaning that it can heat a home all year round, day and night, without requiring assistance from another heating system.
The more efficient a solar water heating system is, the more money a homeowner will save on monthly bills. The most efficient active systems require only a fraction of the electricity (or equivalent fuel source) that traditional water heating systems use. Efficient solar water heating systems will also add considerably to a home’s resale value, reflecting the savings that the next owner will make on their heating bills.
One of the most exciting aspects of solar water heating systems like the SunPump is that such systems are well-suited to being combined with radiant floor heating. Radiant floor heating (heating homes via hot water pipes in the floor), offers homeowners the most comfortable, luxurious heating experience available on the market today. Radiant floor heating systems are also highly efficient in their use of energy, meaning that a system that incorporates radiant floor heating will save homeowners even more on their monthly bills.