Solar Thermal Systems consist of:
- Flat plate collectors
- Insulated piping
- Circulating pump
- Expansion tank
- Hot-Water storage tank(s)
- Heat exchanger
- Antifreeze solution
- Controller
- Valves
- Gauges
Commercial or industrial solar thermal systems are most cost effective in facilities with
water heating systems that are expensive to operate, or in operations such as laundries
or kitchens that require large quantities of hot water. A solar thermal system can meet
most of a facilities hot water needs and significantly reduce water heating bills.
Closed-loop antifreeze systems are the most popular and versatile type of system
installed worldwide. They consist of one or more collectors, insulated piping, a
circulating pump, an expansion tank, a hot-water storage tank, a heat exchanger,
antifreeze solution (propylene glycol), a controller, and some valves and gauges. The
piping loops from the collectors to the heat exchanger and back again. This closed loop
is filled with the antifreeze solution, which stays inside the collectors and piping at all
times. Whenever the sun shines on the collectors, the circulating pump comes on, and
the solar fluid circulates within the closed loop. The fluid gets hot inside the collectors
and travels through the piping to the heat exchanger. The heat exchanger transfers the
heat from the fluid to the water inside the storage tank, which stores the heated water
for your use. As the fluid heats, it expands, so the expansion tank is included to relieve
pressure in the system. When the sun is not shining, the circulating pump simply turns
off, and the fluid stops circulating.
