Solar water heating technology — also referred to as solar thermaltechnology — has been around for ages. But its effectiveness hasn’t lead to broad adoption in the United States. Why you ask?
As a brief review, solar hot water systems don’t generate electricity like a photovoltaic (PV) system does. Instead, they use the sun’sthermal energy to directly heat water, bypassing the step of electricity generation. This has important implications for building energyefficiency. Solar thermal technology can be used for water heating,space heating and space cooling. Solar water heaters, however, are themost common application of solar thermal technology. In a word, they can be great investments: compared to PV panels, solar hot water systemshave relatively low up-front costs and often offer shorter paybackperiods.
Solar hot water systems were incredibly popular in the 1970s andearly 1980s, a time that saw the energy crisis of 1973. Partly as aresponse to rising oil prices, President Carter’s administrationestablished rebates and other incentives to encourage the adoption ofrenewable energy systems. During this time, there were as many as 500U.S. manufacturers of solar water heating equipment. This numberdwindled to a mere five, however, after the federal government curtailed the incentive programs.
The government wasn’t the only factor behind solar water heaters’rapid decline. The industry grew quickly and without much oversight, acombination that resulted in a spate of low-quality installations andunder-performing systems. As a result, solar water heating got a bad rap for being ineffective. Understandably, a technology that suddenly gotless affordable (due to the axed incentives), and was perceived to beless reliable, quickly fell out of favor.
As a result, new systems were rare in the United States until the2000s, when renewable energy saw increased interest from both consumersand politicians. The few companies who have been in the solar thermalbusiness for the long haul have focused on solar heating for swimmingpools, a smaller market that allowed them to weather their industry’slong downturn. Today’s market looks more promising, though, so we’rehoping this great renewable energy option can regain some of its formerpopularity.
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