Photovoltaic (pv) Electric Systems

Author: Cooler Planet

Photovoltaic (PV) Electric Systems

Photovoltaic systems use solar cells to capture the sun rays and convert that energy into electricity. Such systems allow homeowners to generate electricity in a clean, reliable, and quiet way that can offset the cost of future electricity costs and decrease their dependence on the energy grid.

Photovoltaic cells are generally made from modified silicon, or other semi conductive materials, that absorb and convert sunlight into electricity. Photovoltaic cells are long lasting (the first PV system ever installed in the USA - in 1954 - is still operating today). Most manufacturers warranty their products power output for a minimum of 20 years. But most solar professionals agree that a system should last at least 25 - 30 years.

Types of Solar Cells

There are three basic types of PV modules: monocrystalline, polycrystalline, and thin-film. All modules work well though monocrystalline cells often yield the greatest efficiencies. Thin-film technology typically costs less and its efficiency is ever improving as demand for solar panels grow. A growing variety of manufacturers and models are available in the marketplace today. A solar pro can walk you through the advantages and disadvantages of each system so that you find a design that performs optimally over its multi-decade long lifespan for your application.


How solar electric systems work

Photovoltaic panels are often mounted on a roof and wired into a building via an inverter. The inverter converts the direct current (DC) energy generated through the solar panels into alternating current (AC), the most common type of current used to power buildings in the USA.

Orienting solar panels to the south maximizes the effectiveness of energy collection, and most roofs - from flat to 60-degrees - can accommodate photovoltaic cells.

Orienting solar panels to the south maximizes the effectiveness of energy collection, and most roofs - from flat to 60-degrees - can accommodate photovoltaic cells.

Solar Panels vs Building Integrated Photovoltaic Products (BIPV)

Solar panels are flat panels of photovoltaic arrays mounted on a roof or a pole to capture the sun's rays. They are the traditional arrays used to catch energy from the sun. Because of their standalone design, solar panels are well suited for home retrofits or remodels.

Solar photovoltaic cells, however, are increasingly incorporated into building components such as windows, walls, or roof tiles. The effect provides a seamless integration into a building's design since the BIPV components essentially disappear into the skin of your home. BIPV products work particularly well for new home construction or a significant remodel. And because BIPV panels are made for both photovoltaic and thermal collection systems, designers often place both technologies side-by-side to further maximize efficiencies.

About the Author:

Find more solar panel and solar power information at Cooler Planet.

Article Source: ArticlesBase.com - Photovoltaic (pv) Electric Systems

Tips to Reduce Your Heating and Cooling Costs

Author: David Nelmes

Here are a few tips that will help reduce the load on your heating and cooling systems so that they do not have to work so hard, resulting in further reductions of your heating and cooling costs.



INSULATING AND SEALING



In the summer, the attic is the first layer of defense between your homes living space and the sun. In the winter, the attic is the final layer between your heated air and the frigid air outdoors. The most economical thing you can do is to add additional layers of insulation to your attic or have more insulation blown in.



In the winter, if you have older windows, seal the windows with plastic, either from weatherization kits that are readily available or by simply cutting plastic sheets and securing them with duct tape. Also add weather stripping to doors and replace screens with storm windows or cover the screens with plastic.



ATTIC VENTILATION



During the summer, your attic crawl space can easily exceed 130 degrees. Proper venting, such as installing a 'ridge vent' can be helpful in allowing the heat at the attic's highest level to more easily escape.



If you had chosen to add more insulation to your attic space, check to make sure none of your eaves are blocked and that your attic still has airflow from each eave to the ridge vent.



Another great ventilation aid is to install a solar powered exhaust vent that only turns on at high temperature and uses only the power of the sun to provide this extra ventilation. Since there is no wiring necessary, any basic carpenter or handyman can install this form of vent.



EXHAUST SYSTEMS



Your bathroom fans, stove top fans and clothes drier are all items that exhaust your heated or cooled air outside, requiring air to be drawn in from the outside, resulting in hot humid air or cold frigid air being sucked into your home when you least desire it.



Do not use your clothes drier on extreme temperature days, such as summer days at 90 degrees and greater or on winter days at 20 degrees or lower. In the summer, the heat of the day peaks between 3pm and 6pm, so run your drier earlier in the morning or much later at night. Likewise in the winter, the night temperatures may be frigid and drop into the single digits. Run your clothes drier only during the afternoon and early evening when the air is the warmest of the day.



For your bathroom exhaust fans, replace the simple on/off switch with a timed switching device of no more than 60 minutes. It is necessary to ventilate the bathroom, but it's totally wasteful to find that the exhaust fan ran all day while at work, exhausting your heated air outside. You may as well have just left a window open all day.



FREE HEATING AND COOLING



Depending upon your geographic location and the position your home faces, you can take advantage of windows and curtains to add or block heat, depending upon the time of year. In the winter, allow the sun to enter your southern windows during the day, but in the summer, be sure to keeps those blinds drawn.



For summer cooling, install a whole house exhaust system and run it on nights when the outdoor temperature drops. Simply turn the unit on, open your windows and allow the house to cool off naturally, with just a little help from one central fan.



TEMPERATURE SETTINGS



Heating systems are generally designed to provide your home with the capacity to maintain 70 degrees indoors when it's 0 degrees outdoors. By eliminating drafts and simply wearing long sleeve shirts and socks during the winter, you can easily reduce your homes temperature setting to 65 degrees and be totally comfortable. Any lower than that and you may start feeling uncomfortable.



Cooling systems are generally designed to provide your home with the capacity to maintain 75 degrees indoors when it's 95 degrees outdoors. Since the main discomfort issue in the summer is humidity, you can be comfortable in your home at higher temperatures since the homes humidity levels are reduced when running the air conditioner. By eliminating unnecessary exhaust and door openings and closings, you could increase your homes temperature setting to 78 or 80 degrees and be totally comfortable if you dress lightly and keep drapes drawn that favor the suns side of your home.



For either heating or cooling, you can alter the temperature settings from 5 to 10 degrees for when you are not going to be at home for 8 to 12 hours. Making an alteration of any greater amount only leads to your system overworking to recover and this is inefficient. If you are going to be away for days, you can reduce the heating to 55 degrees or raise the cooling temperature to 90 degrees and this will prevent freezing issues or baking issues.



You can also install a programmable thermostat to better define the periods where you plan to be home or not, plus you can also set winter heating temperatures lower during the night when you are sleeping and have it bump back up a few degrees a half hour before you awake.



( This article is an authorized excerpt from the book 'The Rewards of Making Energy Efficient Choices' , available at http://www.EnergyEfficientChoices.com )

About the Author:
David Nelmes is a published author and home energy inspector in Pennsylvania, specializing in the fields of Heating and Air Conditioning, Electrical Wiring and Interiors/Insulation. You can visit his web site at http://www.energyefficientchoices.com

Article Source: ArticlesBase.com - Tips to Reduce Your Heating and Cooling Costs

Why solar powered attic fans more popular

One of the more popular uses of solar power in the home is the solar attic fan.As its name implies, a solar attic fan is powered and activated by sunlight. It is installed into the roof of the attic, with its panels facing the sky.

Do you now what the purpose of this solar attic fan is ?, why would we want it to be solar-powered?

The first answer is obvious - to use greener energy and to avoid using energy sources which damage the environment.By using solar power for the fan, we can also save a bit of money on electricity.Solar powered attic fan is the simple fact that it is basically "wireless." You won't have to worry about installing electrical wires and cables into your attic, in order to run your fan.

Actually the main objective is,Since heat rises, all of the heat in a home tends to rise up into the attic. If this heat has no easy outlet, it will simply get stuck up there.This causes the over-heating. When combined with a lack of proper ventilation, this leads to dampness and mildew.Furthermore, when the accumulated attic heat is not allowed to escape, the temperature of the entire home rises.While there are some circumstances under which you want to warm up your home, there are other circumstances under which you would prefer to cool it down. A lack of sufficient ventilation in a hot attic can make matters difficult. Thus, an solar attic fan can play an important role in allowing you to control the temperature of your home.