Solar water heaters capture the energy of the sun using solar panels and transfer the heat to the water in a storage tank. There are several configurations for the system including gas or electric heat boosting systems in the tanks.
This overview of solar water heaters will help you make an informed decision regarding them. Use the information to compare solar water heaters with tradition gas or electric, hybrid electric models or tankless water heaters.
How Solar Water Heaters Work
The basic configuration employs solar panels mounted on the roof of a home. From 2-6 panels are common. The solar panels collect heat from the sun the way a black car hood does on a sunny day. The more panels are employed, the more heat will be collected.
A pipe travels back and forth through the solar panels. It contains a fluid containing glycol that can quickly absorb heat. It also won’t freeze in cold weather. The liquid in the pipe is circulated by a pump. The heated fluid travels to the water storage tank where the heat transfers out of the fluid through a heat exchanger, effectively heating the water. It travels back to the panels to collect more heat. The circulation is continuous until the water in the tank is heated to the desired temperature. The pump turns back on when there is a demand for hot water.
In very sunny, warm climates, the solar panels may be sufficient. However, most systems use a storage tank that has a gas burner or electric heat coil as a backup for cloudy days or for high-demand periods.
To assist with the efficiency and performance of the systems, some us extra storage tanks, so that water can be heated in off-peak times or during sunny conditions and stored for later use.
Pros and Cons of Solar Water Heaters
Here’s a look at the strengths and weaknesses of this type of water heater. They are a good source of information when comparing solar water heaters with other types.
Pros: Once the system is in place, hot water is produced very inexpensively. The sunnier the climate and the more panels, the less the backup gas or electric system will need to be used. Ideally, the only power needed for the system will be to run the fluid pump. The cost of heating water for your home can be reduced by 75% or more.
These systems are very eco-friendly. They are typically manufactured from recyclable materials and some contain recycled material. Solar water heaters dramatically cut down on carbon emissions released when electricity is produced.
Solar panels are very durable and so is the pipe. They should last 30+ years. The pumps should last 20-25 years too. Tanks will last 15-20 years. So, once the system is in place, it will offer service for much longer than other types of systems.
Cons: The biggest drawback to these systems is their cost. Single panel systems cost $2,300-$3,200. A 3-panel system costs $4,000+. Extra panels cost $750 to more than $1,000 and the tanks range from $800-$1,500 depending on the size and type.
When to Consider a Solar Water Heater
The sunnier your climate is, the more these systems make sense. They are also popular with enthusiasts of environmentally responsible technology. The longer you plan to live in the home where the solar water heater is installed, the more cost-effective it will be in the years ahead. This technology offers an exciting alternative to conventional water-heating methods and should become an even more viable option for more homeowners in the future.