One homeowner shares the challenges and rewards of installing a solar hot water system at his home near Naches, Washington.
Thirty-five years ago, when my wife and I were college students living on a budget, the house we called home was a dirt-floored log cabin in northwestern Montana. We had no modern conveniences—just a cookstove for warmth, an underground pit for keeping food cool, an artesian spring for filling the old cast-iron bathtub, and an outhouse built from a leftover Steinway piano crate. Ah, the good life.
It’s easy to wax nostalgic over those bygone days of the 1970s, when oil shortages pushed the then-novel idea of renewable energy (RE) into the limelight. When it came to RE solutions for the home, most people experimented, with one eye to basic science and another to the spare parts bin. We were no different. Back then, our solar hot water system was nothing more than a black metal barrel in a wooden box with an old window mounted to the front, facing south.
These days, as I seek to improve the energy efficiency of our modern home in Yakima County, Washington, I am continually amazed by how much the times have changed. Information is abundant, and prefab parts are plentiful—to the point of being overwhelming for greenhorns on the DIY RE scene. When I started researching a solar hot water (SHW) system for our three-bedroom home, I had no delusions about the project’s complexity. I knew that installing and maintaining a modern system would be a tad more involved than our previous “black barrel” method. For one thing, this time, my basic plumbing and electrical skills were up against two existing electric water heaters and 13-year-old plumbing in hard-to-reach places.
All I can say is thank goodness for the ever-evolving home improvement genre. Taking notes in the margins of back issues of Home Power and studying online resources armed me with more information—and much-needed confidence—to tackle the task. First up: determining which system would work best for our home, budget, and site.
In our sometimes-snowy region where winter temperatures drop below 0°F, the logical choice was a closed-loop system. Unlike open-loop systems that pump potable water through the collectors and piping, closed-loop systems circulate a solution (usually propylene glycol antifreeze) through an isolated loop between the collectors and storage tank. A heat exchanger transfers the solar-generated heat to the domestic water system.
Although I’d considered high-tech evacuated-tube collectors, the cost-effectiveness of flat-plate collectors won me over, and I already knew what I wanted: low-iron tempered glass for good sunlight transmission and longevity, a selective coating for more efficient heat gain, sturdy frame construction for durability, and polyisocyanurate insulation on the collector’s sides and back to minimize heat loss. A number of manufacturers make flat-plate solar collectors that fit my criteria, so my decision became more about the manufacturers and their retailers than the collector itself. I evaluated each on pricing, customer service, Web sites, and shipping costs. Then, I considered the feedback from articles in Home Power and performance data collected by the Solar Rating and Certification Corporation.