Solar Tour

Solar water heating systems

There are over 60 million solar water heating systems in the world, with hundreds of thousands of systems in the United States and thousands in Illinois.  Easily integrated with conventional gas, electric, forced air, radiant floor and pool heating systems, solar water heaters utilize reliable, proven materials and technologies.  Space and water heating are two large energy expenses for an Illinois home or business.  Solar thermal offers an ideal solution to minimize rising and volatile utility costs while reducing pollution and reliance on fossil fuels such as natural gas, an increasingly imported source of energy. Systems cost little to run and last decades with minimal maintenance.  Based on a study by the Appraisal Institute, a home’s value increases $20 for every $1 reduction in annual energy bills.

How solar water heating works

Solar collectors trap solar heat in much the same way a car’s interior does when it sits in the sun. Water or anti-freeze is heated as it is pumped through tubes in the collector.  A heat exchanger transfers this heat to a water storage tank.  Solar heated water in the storage tank can be used immediately or later for daily hot water needs.  The water passes through the gas/electric heater, which boosts temperature if and as needed.  A conventional hot water heater’s useful life may be extended because of the solar system’s work. 

Space Heating

Solar heated water can warm a hot-water radiant floor system, or pass through a special furnace fan coil for any traditional forced air furnace.  The furnace fan blows air across the coil, reducing the need for natural gas or other fuel. 

Types of collectors

Flat plate collectors are efficient at heating a high volume of water to a medium temperature (generally up to 180 degrees).  They are insulated, aluminum framed boxes covered by tempered glass.  Inside, heat is collected by absorber fins, reflectors or concentrators.  Flat plate collectors are currently the most common collector type.

Evacuated tube collectors heat a lower volume water but to higher temperatures.  The collectors are usually made of parallel rows of transparent glass tubes.  Air is removed, or evacuated, from the space between the outside glass tube and the heat pipe within to form a vacuum, which eliminates conductive and convective heat loss. 

Outdoor swimming pools make use of relatively inexpensive unglazed collectors made of UV resistant plastic.  Pool collectors hook right up to the pool’s existing filter pump.  They can deliver up to 100% of a pool’s heat from Memorial Day to Labor Day in Illinois and are one of the most cost-effective applications of solar energy. 

Solar thermal offers an ideal solution to minimize rising and volatile utility costs while reducing pollution and reliance on natural gas, an increasingly imported source of energy.