What is the difference between PV (Photovoltaics) and solar water?
PV turns sunlight into electricity and solar water systems turn sunlight into hot water. A standard solar water heater is equivalent to a 2.5 kw PV system in the amount of energy produced. So pending your energy source a solar water heater is around 1/5 the cost per kw than a PV system.
How does the system work?
Click here to see our easy to follow animation that shows how the system works and includes component information via mouseovers and clicks.
What specific system do I need and what is my financial return?
Our easy to use online calculator will automatically determine your system and calculate future returns.
Will your system work in my home?
Your home must have at least 40 square feet of non-shaded south (preferable), west or east facing roof space and enough room for the tanks (area will depend on hot water demand). In addition, the piping from the collector to the tanks must be sloped and the area must be accessable for the installer to run the piping. Please contact Techsun Solar at 512-656-0858 for a FREE onsite evaluation.
What if there is not enough sunshine to heat the water? Will I run out of hot water?
Solar water heaters act as a pre-heater to your existing water heater energy source. You are not replacing your existing energy source soley with a solar water heater. You will either have a single electric tank with the top element activated or a 2 tank system (one is a fossil fueled backup tank and the other is the solar storage tank). A solar system will reduce your present hot water heater’s energy cost anywhere from 40% to 85% over the course of the year… pending your location.
Why not a single tank design?
Each person within a household according to the Department of Energy requires on average 19 gallons of hot water per day. A single tank design only has one working element 1/3 from the top of the tank. Consequently there is only around 30 gallons of non-solar heated water in an 80 gallon tank. If there are more than 2 people in the home the 30 gallons of heated water will probably not be enough given a lackluster solar day. This is our number one complaint from solar water users of other systems.
In addition there is only 50 gallons of water available in the lower part of single 80 gallon tank for the solar storage. 50 gallons of solar generated hot water is less than the goal and consequently a lower system efficiency. We highly recommend 2 tanks for households with 3 or more residents or a single 120 gallon tank with the top element activated. There is no single tank system configuration that can be utilized by every family size. Obviously for water heaters with gas as it’s fuel a two tank configuration is the only option. See the why us page for more information regarding one tank systems.
What is the difference between your system and other systems?
What about scaling or tank sediment buildup?
The cause of scaling and tank sediment is a combination of hard water and high tank temperatures. Only drain-back systems have high temperature protection capabilities. Many of our local service calls are caused by glycol systems which during the summer months have very high tank temperatures. High temperatures cause scaling within a system’s heat exchanger which greatly reduces the system’s performance. Techsun’s unique system design greatly reduces scale and tank sediment. See our scaling page for more information regarding scaling.
The system efficiency on your calculator for my location seems low as compared to other manufacturer claims.
Every locale has very specific solar radiation and efficiency ratings. Most solar resellers and “industry experts” greatly generalize performance numbers. In addition most people’s true hot water use is sporadic. The federal testing center uses 5 periodic daily draws during the best sunlight hours and exclude hot water use fluctuations. We provide the most valid data possible by utilizing NASA radiation data, real life variables and the actual roof/collector direction in our calculator.
What is your system’s warranty?
We offer a blanket 5 year system warranty, a 12 year collector warranty and a lifetime warranty on the heat exchanger.
Does my family have to change our existing habits to use a solar water heater?
Are there government rebates?
It depends on your location for there are many local, state and federal rebates. Until the end of 2008 there is a national 30% tax credit for a solar water heating system and it’s installation. Please utilize our easy to use online calculator and check www.dsireusa.org for detailed information.
Will your system freeze or overheat?
No. Our system is based on the drain-back design. A sensor which is connected to the collector triggers the controller to turn off the pumps when freezing or over heating temperatures are reached. Once the pumps stop the water will drain from the collectors to the drainback tank.
How many years will the system last?
The solar system is designed to last 30+ years. The pumps and your water heater itself may need to be replaced after 15 years although I have seen many last 20+ years.
Is maintenance required for your system?
Pending your water quality (sediment buildup) we recommend a sediment filter that should be changed 4 or 6 months pending your hot water use. The filter replacement cartridges are only $4.50 and are available at most hardware stores.