Other cities won’t have it so easy. Take Atlanta. Residents buy energy from Georgia Power, which is owned by investors. As things stand, Atlantans have no control over how their power is generated, though that may change. In 2019, Georgia Power, by state law, has to update its energy plan. Ted Terry, director of the Georgia chapter of the Sierra Club, says the nonprofit is working with Atlanta officials to incorporate renewables, primarily solar, into the state’s plan. Developing such energy sources on a scale that can power a metro area with 5.8 million people, as in Atlanta, or 7.68 million in the San Francisco Bay Area, or 3.3 million in San Diego, will prove challenging. But it doesn’t seem impossible. In 2015, California set a goal of deriving 50 percent of its energy from renewable sources by 2030. Its three investor-owned utilities—Pacific Gas & Electric, Southern California Edison and San Diego Gas & Electric—are poised to achieve that goal just two years from now, or ten years early.
On most horizontal wind turbine farms, a spacing of about 6–10 times the rotor diameter is often upheld. However, for large wind farms distances of about 15 rotor diameters should be more economical, taking into account typical wind turbine and land costs. This conclusion has been reached by research[62] conducted by Charles Meneveau of the Johns Hopkins University,[63] and Johan Meyers of Leuven University in Belgium, based on computer simulations[64] that take into account the detailed interactions among wind turbines (wakes) as well as with the entire turbulent atmospheric boundary layer.
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.
Enhanced geothermal systems (EGS) are a new type of geothermal power technologies that do not require natural convective hydrothermal resources. The vast majority of geothermal energy within drilling reach is in dry and non-porous rock.[161] EGS technologies "enhance" and/or create geothermal resources in this "hot dry rock (HDR)" through hydraulic stimulation. EGS and HDR technologies, such as hydrothermal geothermal, are expected to be baseload resources which produce power 24 hours a day like a fossil plant. Distinct from hydrothermal, HDR and EGS may be feasible anywhere in the world, depending on the economic limits of drill depth. Good locations are over deep granite covered by a thick (3–5 km) layer of insulating sediments which slow heat loss.[162] There are HDR and EGS systems currently being developed and tested in France, Australia, Japan, Germany, the U.S. and Switzerland. The largest EGS project in the world is a 25 megawatt demonstration plant currently being developed in the Cooper Basin, Australia. The Cooper Basin has the potential to generate 5,000–10,000 MW.
Around the world many sub-national governments - regions, states and provinces - have aggressively pursued sustainable energy investments. In the United States, California's leadership in renewable energy was recognised by The Climate Group when it awarded former Governor Arnold Schwarzenegger its inaugural award for international climate leadership in Copenhagen in 2009.[156] In Australia, the state of South Australia - under the leadership of former Premier Mike Rann - has led the way with wind power comprising 26% of its electricity generation by the end of 2011, edging out coal fired generation for the first time.[156] South Australia also has had the highest take-up per capita of household solar panels in Australia following the Rann Government's introduction of solar feed-in laws and educative campaign involving the installation of solar photovoltaic installations on the roofs of prominent public buildings, including the parliament, museum, airport and Adelaide Showgrounds pavilion and schools.[157] Rann, Australia's first climate change minister, passed legislation in 2006 setting targets for renewable energy and emissions cuts, the first legislation in Australia to do so.[158]
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.

Biofuels include a wide range of fuels which are derived from biomass. The term covers solid, liquid, and gaseous fuels.[73] Liquid biofuels include bioalcohols, such as bioethanol, and oils, such as biodiesel. Gaseous biofuels include biogas, landfill gas and synthetic gas. Bioethanol is an alcohol made by fermenting the sugar components of plant materials and it is made mostly from sugar and starch crops. These include maize, sugarcane and, more recently, sweet sorghum. The latter crop is particularly suitable for growing in dryland conditions, and is being investigated by International Crops Research Institute for the Semi-Arid Tropics for its potential to provide fuel, along with food and animal feed, in arid parts of Asia and Africa.[74]

Photovoltaics were initially solely used as a source of electricity for small and medium-sized applications, from the calculator powered by a single solar cell to remote homes powered by an off-grid rooftop PV system. Commercial concentrated solar power plants were first developed in the 1980s. The 392 MW Ivanpah installation is the largest concentrating solar power plant in the world, located in the Mojave Desert of California.