The Time is Right for Solar Hot Water

Arguments against solar panels have focused on prohibitive costs, but current federal, state and utility incentives have made this the best time to go solar.

A solar hot water system turns the sun’s energy into heat. There are several different solar thermal designs, but all are based on the same simple principle of circulating a fluid, usually water or a food grade anti-freeze (propylene glycol) through solar panels located on your roof. That heat is then transferred to a solar storage tank, which then feeds into your gas or electric tank by use of a heat exchanger.

System Types

Your system can be either a pressurized “closed loop” glycol or anti-freeze system, or a “drain-back” system. The closed loop antifreeze and drain-back names come from how the system is protected from freezing of the solar transfer fluid. Your system can also use either “flat plate” or “evacuated-tube” collectors. Evacuated tube collectors are said to “preform” better than flat plate collector in cold climates and under overcast skies, however real-world testing shows this to be untrue. All system types have pros and cons, and each is suitable for a specific application. Your best bet is to have a solar designer do a site visit to recommend the best option for your home.

A typical system will have 3 main parts, the solar collectors, mounted on the roof or ground, a solar storage tank and an operating system. The operating system will have a pump and control, and if a closed loop, additional parts are needed for safe and correct operation. All piping that runs between the panels and the solar storage tank should be insulated with good quality pipe insulation. Any pipe insulation exposed to sunlight needs to be covered to protect it from ultraviolet rays.

Drain-back solar hot water heating systems are low maintenance, with cleaning of panels and draining or flushing of the solar storage tank usually being all that is necessary. Closed loop glycol systems need more including periodical testing of the anti-freeze fluid and replacing when needed or every 5 to 10 years depending on the manufactures recommendations. Additionally, fluid levels may need topping off and safety components need to be check for proper operation either by the system owner or a qualified technician.

Typical cost of an installed solar hot water system for a family of 4 is between $6500 and $10,000. A 22% Federal Tax Credit good till Dec. 31, 2021, and some utility incentives help to lower the initial cost. With a 30-to-40-year life a solar hot water heating system can save homeowners substantial amounts of money and pay for itself two to three times. Other benefits include lower future heating cost, reduced greenhouse gas emissions and increased home value.

Sunworks personal have been installing and servicing solar hot water heating systems since 1980. We have experience with all types of systems including the good, bad and really ugly ones. We do free site visits and can discuss which system will work best for you. Call us today for a free solar hot water site visit today.