Another economic measure, closely related to the energy payback time, is the energy returned on energy invested (EROEI) or energy return on investment (EROI),[131] which is the ratio of electricity generated divided by the energy required to build and maintain the equipment. (This is not the same as the economic return on investment (ROI), which varies according to local energy prices, subsidies available and metering techniques.) With expected lifetimes of 30 years,[132] the EROEI of PV systems are in the range of 10 to 30, thus generating enough energy over their lifetimes to reproduce themselves many times (6–31 reproductions) depending on what type of material, balance of system (BOS), and the geographic location of the system.[133]
Additions of small amount (0.5 weight %) of nanoreinforcement (carbon nanotubes or nanoclay in the polymer matrix of composites, fiber sizing or interlaminar layers can allow to increase the fatigue resistance, shear or compressive strength as well as fracture toughness of the composites by 30–80%. Research has also shown that the incorporation of small amount of carbon nanotubes/CNT can increase the lifetime up to 1500%.
Geothermal power is cost effective, reliable, sustainable, and environmentally friendly,[130] but has historically been limited to areas near tectonic plate boundaries. Recent technological advances have expanded the range and size of viable resources, especially for applications such as home heating, opening a potential for widespread exploitation. Geothermal wells release greenhouse gases trapped deep within the earth, but these emissions are much lower per energy unit than those of fossil fuels. As a result, geothermal power has the potential to help mitigate global warming if widely deployed in place of fossil fuels.

Renewable energy variability is a problem for corporate buyers. But what is undesirable to buyers is attractive for insurance companies, whose core business revolves around managing weather-related risks. VFAs sit on top of a new or existing PPA and are effectively designed to pay the corporate buyer when they’re getting less renewable power than they contracted for, and give money to the insurer when there’s more.

Stop getting twisted!! Gold Plated Contacts Heavy 30 amp Per conductor slip ring total 180 amps....Great for even heavy 12 volt environment wind generators as used in our Cat 5 and Freedom II Dual PMA Turbines This rotating connector will be great for the wind generator. The current can be split up in DC applications by using two conductors to cut down on the resistance. If you have application specific questions feel free to ask me before buying. Has 3 mounting holes in collar and long wires for easy installation Shared Specifications Wires 6 Current 0~30A Voltage 600 VDC/VAC Max speed 250RPM Overall diameter 30mm Length 66mm Contact Material Precious Metal:gold-gold Contact Resistance <2mOhm Housing Material Plastics Torque 0.06N.
Interest in recycling blades varies in different markets and depends on the waste legislation and local economics. A challenge in recycling blades is related to the composite material, which is made of a thermosetting matrix and glass fibers or a combination of glass and carbon fibers. Thermosetting matrix cannot be remolded to form new composites. So the options are either to reuse the blade and the composite material elements as they are found in the blade or to transform the composite material into a new source of material. In Germany, wind turbine blades are commercially recycled as part of an alternative fuel mix for a cement factory.

Throughout the country, more than half of all U.S. electricity customers now have an option to purchase some type of green power product from a retail electricity provider. Roughly one-quarter of the nation's utilities offer green power programs to customers, and voluntary retail sales of renewable energy in the United States totaled more than 12 billion kilowatt-hours in 2006, a 40% increase over the previous year.
In terms of ocean energy, another third-generation technology, Portugal has the world's first commercial wave farm, the Aguçadora Wave Park, under construction in 2007. The farm will initially use three Pelamis P-750 machines generating 2.25 MW.[44][45] and costs are put at 8.5 million euro. Subject to successful operation, a further 70 million euro is likely to be invested before 2009 on a further 28 machines to generate 525 MW.[46] Funding for a wave farm in Scotland was announced in February, 2007 by the Scottish Executive, at a cost of over 4 million pounds, as part of a £13 million funding packages for ocean power in Scotland. The farm will be the world's largest with a capacity of 3 MW generated by four Pelamis machines.[47] (see also Wave farm).
A photovoltaic system converts light into electrical direct current (DC) by taking advantage of the photoelectric effect.[51] Solar PV has turned into a multi-billion, fast-growing industry, continues to improve its cost-effectiveness, and has the most potential of any renewable technologies together with CSP.[52][53] Concentrated solar power (CSP) systems use lenses or mirrors and tracking systems to focus a large area of sunlight into a small beam. Commercial concentrated solar power plants were first developed in the 1980s. CSP-Stirling has by far the highest efficiency among all solar energy technologies.
United Nations' Secretary-General Ban Ki-moon has said that renewable energy has the ability to lift the poorest nations to new levels of prosperity.[14] In October 2011, he "announced the creation of a high-level group to drum up support for energy access, energy efficiency and greater use of renewable energy. The group is to be co-chaired by Kandeh Yumkella, the chair of UN Energy and director general of the UN Industrial Development Organisation, and Charles Holliday, chairman of Bank of America".[147]
Solar heating systems are a well known second-generation technology and generally consist of solar thermal collectors, a fluid system to move the heat from the collector to its point of usage, and a reservoir or tank for heat storage and subsequent use. The systems may be used to heat domestic hot water, swimming pool water, or for space heating.[21] The heat can also be used for industrial applications or as an energy input for other uses such as cooling equipment.[22] In many climates, a solar heating system can provide a very high percentage (20 to 80%) of domestic hot water energy. Energy received from the sun by the earth is that of electromagnetic radiation. Light ranges of visible, infrared, ultraviolet, x-rays, and radio waves received by the earth through solar energy. The highest power of radiation comes from visible light. Solar power is complicated due to changes in seasons and from day to night. Cloud cover can also add to complications of solar energy, and not all radiation from the sun reaches earth because it is absorbed and dispersed due to clouds and gases within the earth's atmospheres.[23]

A heat pump is a device that provides heat energy from a source of heat to a destination called a "heat sink". Heat pumps are designed to move thermal energy opposite to the direction of spontaneous heat flow by absorbing heat from a cold space and releasing it to a warmer one. A solar-assisted heat pump represents the integration of a heat pump and thermal solar panels in a single integrated system. Typically these two technologies are used separately (or only placing them in parallel) to produce hot water.[180] In this system the solar thermal panel performs the function of the low temperature heat source and the heat produced is used to feed the heat pump's evaporator.[181] The goal of this system is to get high COP and then produce energy in a more efficient and less expensive way.
This wind generator makes a nice addition to a solar panel system with a small battery bank (my bank is 12vdc with 500 amp hours). The wind generator averages anywhere from 2 to 10 amps on most occasions here in northern Indiana. I have seen the wind generator put out as much as 25 amps during heavy wind conditions (i.e. storms). If you plan to run a large battery bank system then you may want to look into some of the larger KW wind generators or build a solar panel system. I do love the sound of this thing. I would not call it whisper, but it has a nice whirl sound to it when it is charging that puts me to sleep at night. By the way, know your math and do things right. You will find yourself installing some heavy gauge wiring to lower voltage drops that can be a bear to work with.
Most in the industry agree that 11 m/s (24.6 mph) makes for a good rated wind speed. Go above it and very soon the turbine should be hard at work to protect itself from destruction, by furling, governing, or shutting down. Those that do not will likely face a short and tortured life. If we agree on 11 m/s, an equation for a realistic rated power number is as follows:
Plant energy is produced by crops specifically grown for use as fuel that offer high biomass output per hectare with low input energy. Some examples of these plants are wheat, which typically yield 7.5–8 tonnes of grain per hectare, and straw, which typically yield 3.5–5 tonnes per hectare in the UK.[68] The grain can be used for liquid transportation fuels while the straw can be burned to produce heat or electricity. Plant biomass can also be degraded from cellulose to glucose through a series of chemical treatments, and the resulting sugar can then be used as a first generation biofuel. - Home Wind Generator for sale and Home Wind Generator kits from WindEnergy7 and Ohio manufacturer of home energy products. If you are looking for a home wind generator, home wind generator system, home vertical wind generator, small home wind generator, home wind generator kit, home wind generator plans, home wind electric generator, home wind power generator, rooftop wind generator, then come to our website to SEE LATEST VIDEOS:

Innovative programs around the country now make it possible for all environmentally conscious energy consumers to support renewable energy directly by participating in the "green" power market. The willingness to pay for the benefits of increasing our renewable energy supplies can be tapped within any market structure and by any size or type of energy consumer.
Large national and regional research projects on artificial photosynthesis are designing nanotechnology-based systems that use solar energy to split water into hydrogen fuel.[52] and a proposal has been made for a Global Artificial Photosynthesis project[53] In 2011, researchers at the Massachusetts Institute of Technology (MIT) developed what they are calling an "Artificial Leaf", which is capable of splitting water into hydrogen and oxygen directly from solar power when dropped into a glass of water. One side of the "Artificial Leaf" produces bubbles of hydrogen, while the other side produces bubbles of oxygen.[54]
Geothermal energy - Just under the earth's crust are massive amounts of thermal energy, which originates from both the original formation of the planet and the radioactive decay of minerals. Geothermal energy in the form of hot springs has been used by humans for millennia for bathing, and now it's being used to generate electricity. In North America alone, there's enough energy stored underground to produce 10 times as much electricity as coal currently does.

A parabolic trough consists of a linear parabolic reflector that concentrates light onto a receiver positioned along the reflector's focal line. The receiver is a tube positioned along the focal points of the linear parabolic mirror and is filled with a working fluid. The reflector is made to follow the sun during daylight hours by tracking along a single axis. Parabolic trough systems provide the best land-use factor of any solar technology.[13] The SEGS plants in California and Acciona's Nevada Solar One near Boulder City, Nevada are representatives of this technology.[14][15]