3 Things you should know when Looking at Solar Water Heating
The advancement in solar thermal heating has resulted in cost effective solar heaters that are almost 94% efficient. This has caused new applications such as solar hot tub heating and much more cost effective hot water heating systems for both pools and homes. Soar Thermal Heating systems compared to Solar Photo Voltiac, are nearly 500% more efficient. As an example the most efficient PV system on the market is only about 16% and cost per Kw is nearly double that of solar thermal.
When looking at solar water heating for pools or spas you should consider the following 3 topics before you make your solar investment:
Open Loop or Closed Loop solar system
Control valve to shut off solar system at night
Location Location Location of solar colllectors
1. Open loop
or closed Loop
solar system is a very important decision especially if you are using salt water or lots of chemicals. Simply, an open loop solar system means the water is circulated directly through the solar system. This means that the chlorine in the water has direct contact with all parts. This type of solar heating system will be the least expensive but will have the shortest life as your may find the chlorine can break down the solar collectors and other parts. Closed Loop
systems uses a heat exchanger as a barrier between the solar system fluid and the pool spa water. While this system costs more. The advantages are that you can run the system year round by using glycol or antifreeze. You also will find the life expectancy of the system is greatly increased.
2. SolarControl System- When designing a solar pool system or solar spa, you need to consider water flow. There is no need to circulate the water through the solar system at night. As a matter of fact, this can result in a negative heat loss. A solar control system will have two temperature sensors, one sensor is placed on the output side of the collectors and will measure the heat coming from the system. The other sensor will measure the current temperature of the pool or spa. If the heat output is greater at the spa and the water temperature is less than required (heat demand) then the system will ensure water flows through the collectors. This is done via an automated solar bypass valve system. At nights when the water in the pool is hotter than the solar collector, the control system will ensure the solar collector is bypassed and uses the alternative pool or spa heating system.
3. Location- In order for any solar system to be effective, it needs to be in direct sun light. This means a southern exposure with no shading of trees or buildings. As a rule of thumb the slope angle of the solar system should equal the corresponding latitude where it is installed. A solar swimming pool system should be installed where it receives the maximum exposure for the greatest ROI.
Dan Jung- Is the President and founder of Northern Lights Cedar Tubs Inc. As a leader in authentic wood hot tub manufacturing, Dan Jung writes many informative articles on hot tubs tips and tricks. The most common problems with hot tub and spas are often the simplest to fix! Dan's company believes strongly in natural and alternative spa sanitization. Consumers are asking for a low chemical sanitization that is also easy to use. Visit Northern Lights Cedar Tubs http://www.cedartubs.com for more information.
