News about Solar, Wind and alternative green power technologies

Renewable energy is something we cannot avoid thinking about as a nation or as a species for that matter. Our oil reserves are dwindling rapidly and our power needs continue to increase. Alternate forms of energy have come quite a distance in recent years and the one form of renewable energy that has made the most progress is solar energy.

Reaping our power from the sun seems a natural way to go in an effort to replace the conventional fossil fuel burning mind set humanity has developed over the last century. Sunshine is plentiful, it is powerful, and it is inexpensive post installation – relatively speaking.

Solar power is a magnificent means by which we can eventually save the earth after years of carbon emission abuse and we can curb and eventually stop global warming. The quantity of power that buffets the earth’s atmosphere is 1667 watts per square meter. Solar experts are excited to state to anyone who will listen that the amount of energy that lands on the earth in only one hour is plentiful enough to more than power the entire earth for one year.

This article is about solar power technologies that are available today. The hope is that it will be a simple overview of a significant source of alternative energy that can eventually replace our current polluting conventional methods of generating power.
Concentrated Solar Power or CSP comes in three varieties.

There are parabolic troughs that are bowed in an angular fashion. Think of a feeding trough for animals and you will get an idea of the general shape. The sunlight is concentrated or focused into a collector or receiver that will heat up a transfer liquid then in turn operates a generator.

Power Tower

This solar technique is for generating steam that is utilized as a force to energize a generator that creates electrical current. The system can generate anywhere from fifty to two hundred Megawatts of energy. An array of mirrored or reflecting plates or dishes are placed so the capture and focus the suns irradiated energy toward a tower that concentrates the power from the array.

Stirling Solar Dish Engine

This method of solar power concentrates the sun’s rays straight into electrical current. It uses a capture dish that looks much like a satellite receiver dish with a reflective surface.
 
Photovoltaic Units [PV]

A photovoltaic system converts the sun’s energy to electrical current with the aid of a semi conductor. It is probably the most common form of solar power in use and it relies heavily on silicon, which is always in short supply and high demand to manufacture the semi conductors.

The PV’s are available in various forms and dimensions but all have the same mechanism of action. Singular photovoltaic cells are linked so they form a photovoltaic module and they are then joined to design an array. These PV arrays then work together as a photovoltaic system or unit.

Solar Tracker
 
Not a form of solar power but an advancement in technology to make solar power more efficient and productive. This device is used to orient the various sun capture devices discussed above – solar photovoltaic panels, concentrated solar reflectors and stirling solar dishes into the sun. The position of the sun obviously moves during the day and according t the season and the solar tracker positions the unit where it will generate sunrays most effectively.

Solar trackers come in different dimensions and varieties, levels of complexity and capability. A familiar type of solar tracker is the heliostat comprised of a mobile mirror that reflects the sun as it moves, toward a predetermined location but there are other methods of operation as well.

The disparity between concentrated solar power and photovoltaics is the CSP is utilized in a plant installation to provide larger amounts of electricity for a utility scale producer. CSP’s are engineered to work in a solar power facility.

The photovoltaics are utilized in smaller installations and for things like calculators, various charging apparatus for tech gadgets, highway emergency phones, solar lighting units, satellites, and the rooftops of homes to provide residential power supplies and free electrical current. In many cases, homeowners will generate an excess of power and sell it back to the power utility grid from PV powered backyard and roof top units.