Campers have known the benefit of solar water heating, but homeowners are just starting to see the benefits of letting the sun heat their water instead of paying the power company to do it for them. There are two different types of solar heating systems: passive, which doesn’t rely on circulating pumps and controls, and active, which does.
You will still need a well-insulated storage tank so don’t throw away your water heater just yet. You can opt to add a solar storage tank which has additional outlets and inlets that connect it to and from the collector to form a two-tank system. In which the solar water heater preheats the water making the amount of energy needed to heat the water to desired temperature much less. The other option is to go completely solar and get a solar tank that has a back up water heater in it. Since nights and cloudy days can have a significant effect on how much water is heated by the sun.
For us needing a residential system we have three options:
- Evacuated-tube solar collectors
- This system features parallel rows of transparent glass tubes. The tube is made of a glass outer tube with a metal absorber tube attached to a fin. This fin has a coating which absorbs solar energy nut stops radiative heat loss. Though this system is used more in commercial applications it is available for residential use also.
- Flat-plate collector
- For this system glazed flat-plate which are insulated are contained inside a weatherproof box. The box will have a dark absorber plate situated under one or more glass/plastic cover. There is also a unglazed flat-plate collector system that is typically found for heating pool water. This system also has a dark absorber plate, which can be made of metal or plastic, but it does not have a cover or enclosure.
- Integral collector-storage systems
- These can also be called a ICS or batch system, as they feature black tanks(s) or tubes in an insulated, glazed box. This is a two tank system as cold water will first past through the solar collector to preheat it then continue on to a conventional water heater. This system will always be a source of reliable hot water, though it can only be installed in climates that no to a mild-freeze because of the possibility of the outdoor pipes freezing or bursting in sever weather.
For those who want an active solar water heating system you can use one of two systems. The first is a direct circulation system which uses pumps to move the water through the collector and into the home. Once again only advised in mild climates because of the damage freezing can have on the outdoor parts of the system. The second is an indirect circulation system which uses an alternative non-freezing fluid through the collectors and then into a heat exchanger. Where the water is the heated before flowing into the home. This system is designed to withstand freezing temperatures so is ideal for sever cold winter areas.
Your solar water heating system can be as simple or as complex as you wish. As any camper knows you can hang water in a black bag and have a hot shower in after a few hours.
You need to make a list of what you truly want your system to accomplish, how you wish it done (by professionals or as a DIY), how much you wish to invest, and so on. Then do in-depth research for your area, talk to other who have a system, try it out on your pool (if you have one), then do it. You will be amazed at the difference it will make in your energy usage.
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