In 1995, we reduced the amount of electricity we used by 17 percent in one fell swoop. How'd we do it? We built a very simple solar water heater.
On average, 25 percent of your home's energy goes for water heating, 50 percent for space heating, and 25 percent for everything else (that means refrigeration, lights, TVs, computers, the works). With water heating taking up that much of your energy budget, a solar water heater will give you a lot of bang for your buck.
You can spend a little or a lot on a solar water heater, depending on what you can afford and how efficient a system you'd like to own. You truly get what you pay for -the more efficient the solar water heater, the more expensive it is. Prices can range from a homemade system like ours that cost about $300 in mostly reused materials plus our labor, up to $5,000 for a state of the art, high efficient evacuated tube collector. In between there are many types of glazed, flat plate collector systems, the ones you've seen for years on roofs.
Luckily, you can see all three types of systems right here on the Peninsula. Our batch water heater is located on the roof of the small garden shop building in our back yard at 310 Lake St. A high-tech evacuated tube model is located on the school district building at 501 Washington Ave., S. in Long Beach, and the Sunrise Pacific Holiday Resort has a flat plate collector system visible on the west side of Pacific Highway 103, about two miles north of Long Beach.
As with any solar device, you need to select a location that faces the equator and has no obstructions to sunlight from 10 a.m. to 2 p.m. to optimize your solar "window" and maximize your solar heating. Note that solar water heaters need sunlight, not sunshine.
A solar water heater can be put anywhere you find the right conditions - on the ground, on the roof of a building, near or far from the house. The only constraints are the length of pipe you'll have to bury and the amount of pipe insulation you'll have to buy to keep the water as hot as possible. Obviously the closer the heater is to the point of use, the less heat loss you'll have and the shorter time you'll have to wait to get hot water to your backup heater in the winter or at the tap in the summer.
Our rather crude water heater is quite effective, producing 140-degree water in the summer. This type of solar water heater is called a "batch" heater because the sun heats water in big volumes all at once, typically the capacity of a standard household water heater, 50 or 80 gallons.
The design of the heater is a simple, insulated wooden "breadbox," with a slanted south-facing facade covered with glass. Inside the breadbox are two black tanks, plumbed in-line ahead of the usual domestic water heater. When you turn on a hot water tap, water flows from the solar heater to your back-up heater (in our case, an electric demand heater) to the tap, pulling new water in from the cold line.
The efficiency of our batch system isn't as great as with one of the more sophisticated flat plate collector systems, whether passive solar with a thermosyphon, or active with mechanical pumps - and it certainly doesn't produce 140 degree water year round like the one on the school building. But, it also cost a lot less. If you decide to install a solar heater, check with your utility for rebates or zero interest loan programs.
Fifteen years ago I got my first lesson about solar water heating when we rescued an old batch heater and took it to our rented home on the Oregon coast. Built as a demonstration project for county fairs, it had languished in a friend's barnyard. Because we didn't want to invest in plumbing for our landlord's benefit, we simply hooked up the solar heater with garden hoses - a cold line from an outdoor tap to the heater, and another hose from the heater to an outdoor shower.
This batch heater/shower installation was proof you could get very hot water with solar alone. Every visitor could feel the too-hot-for-a-shower-without-adding-cold-water and could see that the only thing heating it was the sun. Even with Oregon's notorious rainy weather, we had great outdoor showers from March to October, with zero input from any other energy source.
Victoria Stoppiello is a free lance writer from Ilwaco where many houses face south and have similar potential for solar water heating.