How to Make Solar Hot Water?
Building a solar hot water heater can immediately reduce energy costs and can be utilized in any climate. "On average, if you install a solar panel water heater, your water heating bills should drop 50%--80%". However, it is important to note that it is necessary to have a backup hot water system for those cloudy days or periods of higher use.
1.Find a south facing slope, where sunlight will hit more than other areas. Preferably, you will also want the solar hot water heater to be close to the traditional water heater, thus eliminating some of the heat loss from warm water running through a labyrinthian network of pipes. This south-facing slope will be the home of your new solar hot water heater. Placement and orientation can be the "single most important" factors to consider when constructing a solar water heater.
2.Clean your extra hot water tank with a wire brush and paint it black. Prepare the tank by making sure that you have the correct fittings to run the water from the tank to the rest of the water heating system. Ensure that if you are placing the pv module water heater at an angle for maximum coverage by the sun, and that the cold water inlet is still at the bottom of the tank.
3.Construct the box. The size of the box should allow for the glass front to cover 1 square foot for every 2 to 2.5 gallons of water. This will ensure that you will have a large enough size for adequate solar gain. A standard patio door replacement glass (34 inches X 76 inches) is ideal for a 40 gal. water heater (Resources 3). Obviously, the box should also be big enough to fit the tank.
4.Place the tank into the plywood box and insulate the plywood box further by utilizing double-paned windows or multiple layers of close so that the trapped air will add as an extra measure of insulation. Using silicone to caulk the plywood box will also help seal-in the heat as well as keep unwanted moisture from the outside environment from getting inside. Finish preparing the box by drilling holes for pipes and installing insulation.
5.Connect solar module water heater to the traditional water heater already being utilized in your home. Place two bypass valves leading from the cold water supply to the solar water heater and the traditional water heater so that you can regulate which heating system the cold water flows to. Run piping from the hot water outlet on the solar water heater to the cold water inlet on your traditional heater so that the hot water is running into your existing water heater already hot.