Solar Home Heating Systems
Heat from the sun is not uncommon, in fact solar home heating systems are a viable source of heat in climates with sustained sunshine. It almost sounds like a counter-intuitive home heating system type, after all… when the sun is out, you normally think its going to be warm.
Today’s most effective solar panels can collect enough solar radiation even during overcast conditions to contribute solar heat to a home.
Solar home heating systems can be expensive to purchase and install, though the price has come down significantly in the past decade. In addition, the heat that they produce is renewable and free, except for periodic maintenance or repairs to the system. For those that are willing to try, there are quite a few do it yourself solar projects as well.
Types of Solar Home Heating Systems
As discussed at the Union of Concerned Citizens website, there are two basic types of active solar heating systems, air-based systems and water-based systems. In them, the air or water is heated through the use of photovoltaic panels, often simply called PV panels, solar panels or collectors. Systems that use the solar radiation to heat water are also a type of hydronic heat systems. In cooler climates, an anti-freeze product is mixed with the water to keep it from freezing.
Air solar heating systems collect heat earlier in the day and later in the day than water systems do, but they are less efficient and experience more heat loss. Over the course of a heating season, air and water/hydronic solar home heating systems produce a very comparable amount of heat. The specifics of your climate will indicate which type of system makes the most sense for your home.
How Solar Home Heating Systems Work
Solar home heating systems can be used to heat your entire home, which can cut your energy costs and also help the environment. Whether the heat is collected in air or water, the heat is typically transferred directly into the home for use. Hot air can be distributed through ductwork or directly into a home if the solar panels are installed on the side of the house. Heated water can be channeled through a heat exchanger with air circulated over it. The heated air is then pushed into the home through the ductwork. If enough heat is created, it may be stored or used to heat water as well as space. Hydronic solar home heating systems can be used to pre-heat or partially heat water for a boiler heating system as well.
In a solar heating system for your home, solar radiation collected by photovoltaic panels causes the medium, either water or air, to be heated. In a hydronic or water solar heat system, the water is circulated through the panels with the use of a pump. Ideally, the water temperature is raised only 10-20 degrees F before it is used within the home. Water heated for a longer period of time, to a higher temperature, suffers more heat loss in the process. The consistent flow of heated water travels into the home where the heat is transferred out and distributed to heat the space within the home.
In an air system, the air is heated an additional 70-100 degree F before being used within the home.
Summary, The technology for solar home heating systems continues to advance. Currently, it is cost-effective only in climates with a high percentage of clear days. As the technology improves, thisrenewable source of energy should become more affordable, more efficient and more popular in all parts of the country. The U.S. Energy Information Administration has more information about renewable and alternative fuel technologies.
