Residential Renewable Energy
Full Benefit Conditions For A Solar Water Heater
To get the full benefits of a solar heater you must have an area for the solar collectors that is large enough and has the proper exposure to the sun. A flat roof is ideal because the collectors can usually be oriented to face the sun directly very easily. If you install the collectors on a pitched roof, the ideal direction the roof should face is south.
The collector area required will depend on the daily amount of hot water use, the type of collectors used, the orientation of the collectors and your geographic location. If you consider a standard “package”, you should be sure it is sized appropriately for your specific installation.
If you choose a “Passive” solar water heater, the storage tank(s) will be on the roof. In this event, simple structural bracing may be required. Active solar systems do not normally require structural calculations or roof bracing, because the weight of the collectors is well within normal roof load limits.
An “Active” solar water heater uses a small pump for solar collector circulation, and does not require a tank on the roof. A “Passive”solar heater depends on thermosyphon action, so does not use a pump, but tanks(s) must be on the roof.
OPERATION AND MAINTENANCE:
Your solar water heater should be supplied with operation and maintenance instructions. You will find that there is little, if anything, for you to do once the installer has started your system and checked its operation for the first time. Properly designed solar water heaters are completely automatic and are left in operation year-round. Active systems have a small electronic control with one or more indicator lights to let you know if there is a malfunction. Be sure the instructions specify how your system is protected from freezing! Freeze damage is possible anywhere in Oregon.
How An Evacuated Tube Works
An evacuated tube collection system is one that relies on a series of vacuum sealed glass tubes that are lined up and kept inside a special panel box.
The evacuated tubes are lined up next to each other in a parallel manner.
There are generally four of the tubes in a single system, but this number can be manipulated in order to get the best results for your hot water delivery system.
If you are supplying heated water to a lot of people at once then you will need to make sure that you use a greater number of evacuated tubes in the heating system. Or, if you are using the solar energy to heat up water for a small home then you might need a smaller number of tubes in order to get the system to work efficiently.
In order to keep the tubes safe while still allowing them to function they are covered in a special coating. So then the sunlight will pass on through the clear outer tube and then will be collected by the absorber tube that has been placed inside of it. Generally the absorber that is inside the evacuated tube is made from a glass outer shell with copper inside or in completely glass that is covered in a substance that will collect the solar energy. The absorber is sealed inside of the vacuum in order to avoid any problems with corrosion, and many evacuated tube systems will use foam insulation in order to insure that everything is equally balanced out.
While there are two different types of absorbers that can be used you should know that the straight glass systems are not as high of quality as those that are made out of glass and copper. The reason for this is the fact that glass has less of an ability to continuously adapt under the extreme temperature fluctuations, and this can cause the glass to eventually crack and shatter. This is the reason why it is so important that you will want to make sure that you are getting a quality evacuated tube system so that you can make sure that everything runs as it is supposed to.
You should also know that there are different types of evacuated tube collectors that will operate in different manners as far as the way that they transfer heat is concerned, so you will need to make sure that you are choosing the one that will work with your needs. The more basic machines work by pumping a fluid that can transfer heat like antifreeze through a specialized piece of copper tubing that is shaped like a U, and this is placed inside the glass tubing in order to get the heated fluid flowing. The other type of evacuated tube system works by putting a sealed pipe that is full of fluid that will vaporize when it is heated.
You will need to make sure that when you are looking at an evacuated tube system that you talk to someone about your needs so that they can best match you up with the system that will function the most appropriately. However, no which system you decide to go with you should realize that you will be saving your overall energy consumption by investing in a continuously operating system that relies on a completely renewable energy source. This not only means that you will be paying less to the large energy corporations but you will also be contributing to the environment by lessening your carbon footprint. Not to mention the fact that the evacuated tube system works very well and can heat up water easily because of its design.
Solar Powered Attic Fan
Is your hot attic costing you money?
Solar-powered Fan-Attic ventilation system is the most cost-effective way to cool your attic, lower your energy bills, and make your home a more comfortable place to live — and all you need is sunlight!
The Original Fan-Attic, this is the solar-powered attic fan that started it all! The tenth-generation Fan-Attic is cooling over 80,000 homes since its introduction in 1996.
Photovoltaic Solar Map
This map shows the national solar photovoltaic (PV) resource potential as well as the concentrating solar power (CSP) resource potential for the United States. Annual average solar resource data are shown for a tilt-latitude collector. The data from Hawaii and the 48 contiguous states are a 10km satellite dataset. Representing data from 1998-2005.
What Is A Solar Water Heater?
On a typical single-family residence, there will typically be one or two solar collector panels on the roof. The panels resemble skylights, and will be about 4 feet wide and 8 to 10 feet long.
On a typical multi-family residence building, there can easily be 90+ solar collector panels on the roof.
Cold water is moved via a pump from a water tank and travels through solar collectors in a solar panel. In the process, it is heated up by the power of the sun hitting the solar collectors.
This heat is then carried away from the solar collectors by the water returning to a heated storage tank.
Some solar water heaters have a shut-off valve that automatically closes when the sun goes down in order to save heated water. An auxiliary system will kick in when more hot water is needed. Auxiliary systems run on conventional energy, such as gas or electricity. A controller component regulates the pumping action of the water. The controller will close the check valve that sits between the solar panel and the hot water storage tank. It also turns the auxiliary power on when the solar cycle is not available (when the sun goes down).
Size and Heat Retention
Size is important. Solar water heaters store hot water in a storage tank. A valve closes over the pipe on the storage tank to prevent the loss of heat from the hot water. The larger the storage tank, the longer you can go without recharging the water with heat from the sun. This is especially important for areas where there is frequent rain and overcast skies.
Automated Solar Water Heaters
Automated solar water heaters work by monitoring the water pump in relation to the availability of solar power from the sun. When the sun goes down, the automated solar water heater will stop the pump. In sequence, the valves over the water storage tank will close to prevent the loss of heated water. By preserving the heat in the water storage tank, hot water can be used for bathing or washing dishes even when there is no sunlight to power the solar water heater.
Auxiliary and Passive Solar Water Heaters
Most solar water heaters are not entirely independent of conventional power. When sunlight is not available as a power source, the solar power water heater will switch to auxiliary power (gas or electricity). A solar power water heater can provide on average about 90 percent of hot water from the sun alone. However, a passive solar water heater only provides about 40 percent of the home’s hot water supply. This is due to the auxiliary heating processing in a second storage tank. The tank is preheated, thus more conventional power is necessary to get the water heated up before solar power can kick in.