Our hot water heater is so central to the household, it’s practically a family member. Without it, there would be no hot baths or showers, no warm water for dishes, and only freezing cold hand-washing. Brrr. But there is a price for this inconvenience, and it comes on the electricity bill as well as niggling at my conscience.
Luckily, most local electricity is generated by hydroelectric facilities, a slightly greener power source. Even so, all but the worst laundry goes into cold water, showers are short (ideally), and baths relatively infrequent. So what would improve my relationship with the hot water heater?
What about a solar water heater? Using sunshine as the power source, water can be heated for use in bathing, washing, and even radiant heating. Some configurations rely on solar panels (photovoltaic cells). More commonly, solar water heating – also known as solar thermal – uses solar collectors and a solar tank installed next to an existing water heater. The price for the whole system depends on the size of the home and tank, but is typically $5,000 to $8,000.
So what do you get for your money? The solar collector contains a transfer fluid – water or glycol – that is heated by the sun. It then flows to the solar tank, where it transfers heat to incoming cold water passing through a heat exchanger. The transfer liquid is pumped back to the collector in a loop. If incoming water does not reach a preset temperature, the conventional water heater kicks in and does the remaining heating. Even in grey and drizzly Vancouver, there is enough sun to make a significant difference. In the summer, most household hot water can be generated through solar heating.
Solar water heating systems are durable and can last 25-40 years. Compare that to the 7 to 10 year lifespan of other water heaters (which may last longer if they are doing less of the work, along with a solar buddy). As with any other home renovation, there are reputable companies that deal with the technology and offer warranties, or you can do it yourself.
Solar heating offers various advantages. For a start, it is cheaper – even with the equipment costs, it comes to about 3.5 cents per kilowatt hour. That is about half the cost of electricity and an even smaller fraction of natural gas prices. In addition, there is no greenhouse gas emission from solar heaters – apart from a tiny amount during manufacture and installation.
If you live in British Columbia, the provincial government offers a sales tax exemption for the purchase of equipment. VanCity and Homeworks offer loans, while grants are available from the ecoENERGY Retrofit Program. The Ontario government also has a Ontario Solar Thermal Heating Incentive for industries, institutions, and businesses to promote this technology.
Solar thermal heating is an age-old concept, and its popularity has ebbed and waned over the centuries. Japanese and Israeli homes rely extensively on this source of hot water. So it is hardly new or ground-breaking. But it is timely. While the 20th century saw many technological advances, these also increased our reliance on short-lived fuel sources. Maybe the 21st century will see a return of balance and back to the basics – in a modified form.