Photovoltaics (PV) uses solar cells assembled into solar panels to convert sunlight into electricity. It's a fast-growing technology doubling its worldwide installed capacity every couple of years. PV systems range from small, residential and commercial rooftop or building integrated installations, to large utility-scale photovoltaic power station. The predominant PV technology is crystalline silicon, while thin-film solar cell technology accounts for about 10 percent of global photovoltaic deployment. In recent years, PV technology has improved its electricity generating efficiency, reduced the installation cost per watt as well as its energy payback time, and has reached grid parity in at least 30 different markets by 2014.[115] Financial institutions are predicting a second solar "gold rush" in the near future.[116][117][118]

Green marketing is the sale of green power in competitive markets, where consumers have the option to choose from a variety of suppliers and service offerings, much like they can choose between long-distance telephone carriers. The key difference between green marketing and green pricing is that with green marketing, you are actually switching electricity providers. 
Climate change and global warming concerns, coupled with high oil prices, peak oil, and increasing government support, are driving increasing renewable energy legislation, incentives and commercialization.[10] New government spending, regulation and policies helped the industry weather the global financial crisis better than many other sectors.[24] According to a 2011 projection by the International Energy Agency, solar power generators may produce most of the world's electricity within 50 years, reducing the emissions of greenhouse gases that harm the environment.[25]
In the mid-1990s, development of both, residential and commercial rooftop solar as well as utility-scale photovoltaic power stations, began to accelerate again due to supply issues with oil and natural gas, global warming concerns, and the improving economic position of PV relative to other energy technologies.[34] In the early 2000s, the adoption of feed-in tariffs—a policy mechanism, that gives renewables priority on the grid and defines a fixed price for the generated electricity—led to a high level of investment security and to a soaring number of PV deployments in Europe.
Even with plans to grow as much as 80 percent over the next five years, the city expects to have plenty of energy from these renewable sources. (To be sure, about 2 percent of the time, the Georgetown utility draws electricity derived from fossil fuels. Ross says the city more than compensates at other times by selling excess renewable energy back to the grid—at a profit.)
Third-generation technologies are not yet widely demonstrated or commercialised. They are on the horizon and may have potential comparable to other renewable energy technologies, but still depend on attracting sufficient attention and RD&D funding. These newest technologies include advanced biomass gasification, biorefinery technologies, solar thermal power stations, hot dry rock geothermal energy and ocean energy.
Energy storage is a collection of methods used to store electrical energy on an electrical power grid, or off it. Electrical energy is stored during times when production (especially from intermittent power plants such as renewable electricity sources such as wind power, tidal power, solar power) exceeds consumption, and returned to the grid when production falls below consumption. Pumped-storage hydroelectricity is used for more than 90% of all grid power storage. Costs of lithium ion batteries are dropping rapidly, and are increasingly being deployed as fast acting sources of grid power (i.e. operating reserve) and for domestic storage.
In 2007, the world's first turbine to create commercial amounts of energy using tidal power was installed in the narrows of Strangford Lough in Ireland. The 1.2 MW underwater tidal electricity generator takes advantage of the fast tidal flow in the lough which can be up to 4m/s. Although the generator is powerful enough to power up to a thousand homes, the turbine has a minimal environmental impact, as it is almost entirely submerged, and the rotors turn slowly enough that they pose no danger to wildlife.[48][49]

Go-anywhere rechargeable battery pack keeps your handheld gear Go-anywhere rechargeable battery pack keeps your handheld gear going strong. Charge AA/AAA batteries from the sun or any USB port then power your phone MP3 GPS or perk up your tablet in a pinch. Kit included Nomad 7m v2 Solar Panel and Guide 10 Plus power pack. This ultra-lightweight kit ...  More + Product Details Close


Free electricity isnt all you get from a new home wind Generator, as soon as your system is up, you have improved your home value by atleast an equal amount of the investment. Your green energy home is more likely to sell compared to others with no home generation or emergency power system. Think about it. Look at homes for sale.. Can any of them generate their own free electricity, how many can compete with such a solid green energy capability like your home wind Generator delivers. Its also an attention getter and will bring people to see what its about if you ever need to sell, your home has a dramatic edge and a higher resale value.
Wind turbines are generally inexpensive. They will produce electricity at between two and six cents per kilowatt hour, which is one of the lowest-priced renewable energy sources.[72] And as technology needed for wind turbines continues to improve, the prices will decrease as well. In addition, there is no competitive market for wind energy, as it does not cost money to get ahold of wind.[72] The main cost of wind turbines are the installation process. The average cost is between $48,000 and $65,000 to install. However, the energy harvested from the turbine will offset the installation cost, as well as provide virtually free energy for years after.[73]

Another situation where a small wind turbine can make good sense is in case your province, state, or country has rebates or other incentives that make it cheap to install one (just keep ongoing maintenance and repair cost in mind as well). While we would like to advocate responsible spending of government money, the small wind industry needs many more customers to mature. It takes time and installation numbers for manufacturers to work out the bugs, make better turbines, and make them cheaper.


The tables above are for HAWTs, the regular horizontal “wind mill” type we are all familiar with. For VAWTs the tables can be used as well, but you have to convert their dimensions. Calculate the frontal area (swept area) of the VAWT by multiplying height and width, or for a curved egg-beater approximate the area. Now convert the surface area to a diameter, as if it were a circle: Diameter = √(4 • Area / Pi). That will give you a diameter for the table. Look up the energy production for that diameter and your average annual wind speed and do the following:
The array of a photovoltaic power system, or PV system, produces direct current (DC) power which fluctuates with the sunlight's intensity. For practical use this usually requires conversion to certain desired voltages or alternating current (AC), through the use of inverters.[4] Multiple solar cells are connected inside modules. Modules are wired together to form arrays, then tied to an inverter, which produces power at the desired voltage, and for AC, the desired frequency/phase.[4]
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