Water heaters use a lot of energy, and can account for up to 10 percent of your total energy bill. However, the sun provides heat for free, and we get plenty of it here in the San Joaquin Valley. Solar water heaters can keep water hot for much less than the price of conventional models. If you’re tired of paying large energy bills, then ask yourself if your home is a good fit for a solar water heater.
In essence, a solar water heater is a miniature greenhouse. Small tanks or pipes lie inside a box with a glass or Plexiglas top. The top easily admits visible light, warming up the water in the pipes. Heat does not pass through the top as light does, so it remains trapped inside the box. The longer the collector is exposed to the light, the greater the heat buildup.
Some solar heating systems use pumps to keep the water circulating. Others, called thermosyphon systems, do not use pumps. Instead, they rely on the fact that hot water rises and cold water sinks to keep the water naturally circulating. They are not quite as efficient as pump-driven heaters, but they cost less to maintain and operate. However, they need a strong roof to support the storage tank.
In climates with cold winters, solar water heating systems do not heat the water directly, because the water would be prone to freezing. Instead, the solar system heats up glycol (similar to anti-freeze for your car) and runs it through a heat exchanger. While most people might immediately think that glycol systems wouldn’t be needed in Fresno – think again! There have been many winter nights where the temperature drops into the teens and causes fatal fractures in the non-glycol systems.
The only other requirement that your home needs is a south-facing roof or wall that is unobstructed by trees or anything that casts a shadow. If you have a solid roof, you can even use the thermosyphon system.
To get quality professional advice on solar water heaters and other home comfort systems, please visit us at Donald P. Dick Air Conditioning.We’ve been providing quality service and advice to greater Fresno homeowners for almost 40 years.
Our goal is to help educate our customers in the greater Fresno, California area about energy and home comfort issues (specific to HVAC systems). For more information about solar water heaters and other HVAC topics, download our free Home Comfort Resource guide.
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