Renewable energy commercialization
Renewable energy commercialization involves the deployment of three generations of renewable energy technologies dating back more than 100 years. First-generation technologies, which are already mature and economically competitive, include biomass, hydroelectricity, geothermal power and heat. Second-generation technologies are market-ready and are being deployed at the present time; they include solar heating, photovoltaics, wind power, solar thermal power stations, and modern forms of bioenergy. Third-generation technologies require continued R&D efforts in order to make large contributions on a global scale and include advanced biomass gasification, biorefinery technologies, hot-dry-rock geothermal power, artificial photosynthesis and ocean energy. 
Total investment in renewable energy reached $257 billion in 2011, up from $211 billion in 2010. The top countries for investment in 2011 were China, Germany, the United States, Italy, and Brazil. Continued growth for the renewable energy sector and promotional policies helped the industry weather the 2009 economic crisis better than many other sectors. U.S. President Barack Obama's American Recovery and Reinvestment Act of 2009 included more than $70 billion in direct spending and tax credits for clean energy and associated transportation programs. Clean Edge suggests that the commercialization of clean energy has helped countries around the world pull out of the 2009 global financial crisis.
As of 2012, renewable energy accounts for almost half of new electricity capacity installed and costs are continuing to fall. Public policy and political leadership helps to "level the playing field" and drive the wider acceptance of renewable energy technologies. As of 2011[update], 118 countries have targets for their own renewable energy futures, and have enacted wide-ranging public policies to promote renewables. Climate change concerns are driving increasing growth in the renewable energy industries. Leading renewable energy companies include BrightSource Energy, First Solar, Gamesa, GE Energy, Goldwind, Sinovel, Suntech, Trina Solar, Vestas and Yingli.
Economic analysts expect market gains for renewable energy (and efficient energy use) following the 2011 Japanese nuclear accidents. In his 2012 State of the Union address, President Barack Obama restated his commitment to renewable energy and mentioned the long-standing Interior Department commitment to permit 10,000 MW of renewable energy projects on public land in 2012. Globally, there are an estimated 3 million direct jobs in renewable energy industries, with about half of them in the biofuels industry. According to a 2011 projection by the International Energy Agency, solar power generators may produce most of the world's electricity within 50 years, dramatically reducing harmful greenhouse gas emissions.
Rationale for renewables 
Climate change, pollution, and energy insecurity are significant problems and addressing them requires major changes to energy infrastructures. Renewable energy technologies are essential contributors to the energy supply portfolio, as they contribute to world energy security, reduce dependency on fossil fuels, and provide opportunities for mitigating greenhouse gases. Climate-disrupting fossil fuels are being replaced by clean, climate-stabilizing, non-depletable sources of energy:
...the transition from coal, oil, and gas to wind, solar, and geothermal energy is well under way. In the old economy, energy was produced by burning something — oil, coal, or natural gas — leading to the carbon emissions that have come to define our economy. The new energy economy harnesses the energy in wind, the energy coming from the sun, and heat from within the earth itself.
In international public opinion surveys there is strong support for a variety of methods for addressing the problem of energy supply. These methods include promoting renewable sources such as solar power and wind power, requiring utilities to use more renewable energy, and providing tax incentives to encourage the development and use of such technologies. It is expected that renewable energy investments will pay off economically in the long term.
According to Clean Edge, there's little doubt that the future of energy will be cleaner. The transition from carbon-intensive energy sources like wood, coal, and oil to natural gas and renewables, is well underway. For much of the developed world, and for developing nations, the "future looks increasingly like it will be built off of a mix of energy efficiency, renewables, the electrification of transport, and lower carbon fuels like natural gas".
A 2010 survey conducted by Applied Materials shows that two-thirds of Americans believe solar technology should play a greater role in meeting the country's energy needs. In addition, "three-quarters of Americans feel that increasing renewable energy and decreasing U.S. dependence on foreign oil are the country's top energy priorities". According to the survey, "67 percent of Americans would be willing to pay more for their monthly utility bill if their utility company increased its use of renewable energy".
In a 2010 Chicago Council on Global Affairs public opinion survey, 91 percent believed "investing in renewable energy" is important for the United States to remain economically competitive with other countries, with 62 percent considering this very important. The same poll found strong support for tax incentives to encourage renewable energy development specifically as a way to reduce foreign energy imports. Eight in ten (80 percent) favored tax incentives, 47 percent strongly, and only 17 percent were opposed.
EU member countries have shown support for ambitious renewable energy goals. In 2010, Eurobarometer polled the twenty-seven EU member states about the target "to increase the share of renewable energy in the EU by 20 percent by 2020". Most people in all twenty-seven countries either approved of the target or called for it to go further. Across the EU, 57 percent thought the proposed goal was "about right" and 16 percent thought it was "too modest." Just 19 percent said it was "too ambitious".
Citing the Fukushima nuclear disaster, environmental activists at the 2010 United Nations Climate Change Conference urged bolder steps to tap renewable energy so the world doesn't have to choose between the dangers of nuclear power and the ravages of climate change.
Three generations of technologies 
Renewable energy includes a number of sources and technologies at different stages of commercialization. The International Energy Agency (IEA) has defined three generations of renewable energy technologies, reaching back over 100 years:
- "First-generation technologies emerged from the industrial revolution at the end of the 19th century and include hydropower, biomass combustion, geothermal power and heat. These technologies are quite widely used.
- Second-generation technologies include solar heating and cooling, wind power, modern forms of bioenergy, and solar photovoltaics. These are now entering markets as a result of research, development and demonstration (RD&D) investments since the 1980s. Initial investment was prompted by energy security concerns linked to the oil crises of the 1970s but the enduring appeal of these technologies is due, at least in part, to environmental benefits. Many of the technologies reflect significant advancements in materials.
- Third-generation technologies are still under development and include advanced biomass gasification, biorefinery technologies, concentrating solar thermal power, hot-dry-rock geothermal power, and ocean energy. Advances in nanotechnology may also play a major role". First-generation technologies are well established, second-generation technologies are entering markets, and third-generation technologies heavily depend on long-term research and development commitments, where the public sector has a role to play.
Growth of renewables 
Renewable energy sources were estimated 16.7% of global final energy consumption in 2010. By the end of 2011, total renewable power capacity worldwide exceeded 1,360 GW, up 8%. Of this total, modern renewable energy accounted for an estimated 8.2%, while the share from traditional biomass has declined slightly to an estimated 8.5%. In the power renewables accounted for almost half of the 208 GW of capacity added globally during 2011. Wind and solar photovoltaics (PV) accounted for almost 40% and 30% .
During the five-years from the end of 2004 through 2009, worldwide renewable energy capacity grew at rates of 10–60 percent annually for many technologies. In 2011, UN under-secretary general Achim Steiner said: "The continuing growth in this core segment of the green economy is not happening by chance. The combination of government target-setting, policy support and stimulus funds is underpinning the renewable industry's rise and bringing the much needed transformation of our global energy system within reach." He added: "Renewable energies are expanding both in terms of investment, projects and geographical spread. In doing so, they are making an increasing contribution to combating climate change, countering energy poverty and energy insecurity".
In 2008 for the first time, more renewable energy than conventional power capacity was added in both the European Union and United States, demonstrating a "fundamental transition" of the world's energy markets towards renewables, according to a report released by REN21, a global renewable energy policy network based in Paris. In 2010, renewable power consisted about a third of the newly built power generation capacities.
According to a 2011 projection by the International Energy Agency, solar power plants may produce most of the world's electricity within 50 years, significantly reducing the emissions of greenhouse gases that harm the environment. The IEA has said: "Photovoltaic and solar-thermal plants may meet most of the world's demand for electricity by 2060 -- and half of all energy needs -- with wind, hydropower and biomass plants supplying much of the remaining generation". "Photovoltaic and concentrated solar power together can become the major source of electricity".
However, the International Energy Agency projection may be very pessimistic since official agencies keep underestimating the growth rate of renewables. A report based on the 2012 BP Statistical Review shows an exponential growth in global solar consumption from 2001 to end 2011, with an approximate doubling of consumption every two years. This raises the possibility that solar power could reach 10% of total global power generation by the end of this decade. To accomplish this gain in primary energy share, solar will need to advance from the 55.7 TWh consumption figure of 2011 to approximately 2200 TWh. At current exponential growth rates, those levels could be achieved as early as 2018. Solar would provide 100 percent of the current world energy needs by 2027 if exponential consumption continues.
|Selected global indicators||2004||2005||2006||2007||2008||2009||2010||2011||2012|
|Investment in new renewable capacity (annual)||30||38||63||104||130||160||211||257||256 billion USD|
|Existing renewables power capacity,
including large-scale hydro
|Existing renewables power capacity,
excluding large hydro
|Hydropower capacity (existing)||915||945||970 GWe|
|Wind power capacity (existing)||48||59||74||94||121||159||198||238 GWe|
|Solar PV capacity (grid-connected)||7.6||16||23||40||70 GWe|
|Solar cell production (annual)||6.9||11||24 GWe|
|Solar hot water capacity (existing)||77||88||105||120||130||160||185||232 GWth|
|Ethanol production (annual)||30.5||33||39||50||67||76||86||86 billion liters|
|Biodiesel production (annual)||12||17||19||21 billion liters|
|Countries with policy targets
for renewable energy use
Economic trends 
Renewable energy technologies are getting cheaper, through technological change and through the benefits of mass production and market competition. A 2011 IEA report said: "A portfolio of renewable energy technologies is becoming cost-competitive in an increasingly broad range of circumstances, in some cases providing investment opportunities without the need for specific economic support," and added that "cost reductions in critical technologies, such as wind and solar, are set to continue." As of 2011[update], there have been substantial reductions in the cost of solar and wind technologies:
The price of PV modules per MW has fallen by 60 percent since the summer of 2008, according to Bloomberg New Energy Finance estimates, putting solar power for the first time on a competitive footing with the retail price of electricity in a number of sunny countries. Wind turbine prices have also fallen - by 18 percent per MW in the last two years - reflecting, as with solar, fierce competition in the supply chain. Further improvements in the levelised cost of energy for solar, wind and other technologies lie ahead, posing a growing threat to the dominance of fossil fuel generation sources in the next few years.
Hydro-electricity and geothermal electricity produced at favourable sites are now the cheapest way to generate electricity. Renewable energy costs continue to drop, and the levelised cost of electricity (LCOE) is declining for wind power, solar photovoltaic (PV), concentrated solar power (CSP) and some biomass technologies.
Renewable energy is also the most economic solution for new grid-connected capacity in areas with good resources. As the cost of renewable power falls, the scope of economically viable applications increases. Renewable technologies are now often the most economic solution for new generating capacity. Where “oil-fired generation is the predominant power generation source (e.g. on islands, off-grid and in some countries) a lower-cost renewable solution almost always exists today”. Indicative, levelised, economic costs for renewable power (exclusive of subsidies or policy incentives) are shown in the Table below.
|Power generator||Typical characteristics||Typical
|Large hydro||Plant size: 10 - 18,000 MW||3-5|
|Small hydro||Plant size: 1-10 MW||5-12|
|Onshore wind||Turbine size: 1.5 - 3.5 MW||5-9|
|Offshore wind||Turbine size: 1.5 - 5 MW||10-14|
|Biomass power||Plant size: 1-20 MW||5-12|
|Geothermal power||Plant size: 1-100 MW||4-7|
|Rooftop solar PV||Peak capacity: 2-5 kilowatts-peak||20-50|
|Utility-scale solar PV||Peak capacity: 200 kW to 100MW||15-30|
|Concentrating solar thermal power (CSP)||50-500 MW trough||14-18|
As of 2012, renewable power generation technologies accounted for around half of all new power generation capacity additions globally. In 2011, additions included 41 gigawatt (GW) of new wind power capacity, 30 GW of PV, 25 GW of hydro-electricity, 6 GW of biomass, 0.5 GW of CSP, and 0.1 GW of geothermal power.
First-generation technologies 
First-generation technologies are widely used in locations with abundant resources. Their future use depends on the exploration of the remaining resource potential, particularly in developing countries, and on overcoming challenges related to the environment and social acceptance.
Biomass for heat and power is a fully mature technology which offers a ready disposal mechanism for municipal, agricultural, and industrial organic wastes. However, the industry has remained relatively stagnant over the decade to 2007, even though demand for biomass (mostly wood) continues to grow in many developing countries. One of the problems of biomass is that material directly combusted in cook stoves produces pollutants, leading to severe health and environmental consequences, although improved cook stove programmes are alleviating some of these effects. First-generation biomass technologies can be economically competitive, but may still require deployment support to overcome public acceptance and small-scale issues.
Hydroelectricity is the term referring to electricity generated by hydropower; the production of electrical power through the use of the gravitational force of falling or flowing water. It is the most widely used form of renewable energy, accounting for 16 percent of global electricity generation – 3,427 terawatt-hours of electricity production in 2010, and is expected to increase about 3.1% each year for the next 25 years. Hydroelectric plants have the advantage of being long-lived and many existing plants have operated for more than 100 years.
Hydropower is produced in 150 countries, with the Asia-Pacific region generating 32 percent of global hydropower in 2010. China is the largest hydroelectricity producer, with 721 terawatt-hours of production in 2010, representing around 17 percent of domestic electricity use. There are now three hydroelectricity plants larger than 10 GW: the Three Gorges Dam in China, Itaipu Dam across the Brazil/Paraguay border, and Guri Dam in Venezuela. The cost of hydroelectricity is low, making it a competitive source of renewable electricity. The average cost of electricity from a hydro plant larger than 10 megawatts is 3 to 5 U.S. cents per kilowatt-hour.
Geothermal power and heat 
Geothermal power plants can operate 24 hours per day, providing baseload capacity. Estimates for the world potential capacity for geothermal power generation vary widely, ranging from 40 GW by 2020 to as much as 6,000 GW.
Geothermal power capacity grew from around 1 GW in 1975 to almost 10 GW in 2008. The United States is the world leader in terms of installed capacity, representing 3.1 GW. Other countries with significant installed capacity include the Philippines (1.9 GW), Indonesia (1.2 GW), Mexico (1.0 GW), Italy (0.8 GW), Iceland (0.6 GW), Japan (0.5 GW), and New Zealand (0.5 GW). In some countries, geothermal power accounts for a significant share of the total electricity supply, such as in the Philippines, where geothermal represented 17 percent of the total power mix at the end of 2008.
Geothermal (ground source) heat pumps represented an estimated 30 GWth of installed capacity at the end of 2008, with other direct uses of geothermal heat (i.e., for space heating, agricultural drying and other uses) reaching an estimated 15 GWth. As of 2008[update], at least 76 countries use direct geothermal energy in some form.
Second-generation technologies 
Markets for second-generation technologies have been strong and growing over the past decade, and these technologies have gone from being a passion for the dedicated few to a major economic sector in countries such as Germany, Spain, the United States, and Japan. Many large industrial companies and financial institutions are involved and the challenge is to broaden the market base for continued growth worldwide.
Solar Heating 
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. The systems may be used to heat domestic hot water, swimming pools, or homes and businesses. The heat can also be used for industrial process applications or as an energy input for other uses such as cooling equipment.
Photovoltaic (PV) cells, also called solar cells, convert light into electricity. In the 1980s and early 1990s, most photovoltaic modules were used to provide remote-area power supply, but from around 1995, industry efforts have focused increasingly on developing building integrated photovoltaics and photovoltaic power stations for grid connected applications.
In particularly sunny regions such as Spain, the Middle East, North Africa, the southern USA, India, and parts of China, modern solar modules are close to achieving grid parity. And in countries situated further to the north such as Germany, France, and the Czech Republic, grid parity is expected by 2015. Falling technology prices and the rising costs of fossil fuels are making photovoltaic (PV) power plants increasingly attractive for large investors.
Many solar photovoltaic power stations have been built, mainly in Europe. As of July 2012, the largest photovoltaic (PV) power plants in the world are the Agua Caliente Solar Project (USA, 247 MW), Charanka Solar Park (India, 214 MW), Golmud Solar Park (China, 200 MW), Perovo Solar Park (Ukraine 100 MW), Sarnia Photovoltaic Power Plant (Canada, 97 MW), Brandenburg-Briest Solarpark (Germany 91 MW), Solarpark Finow Tower (Germany 84.7 MW), Montalto di Castro Photovoltaic Power Station (Italy, 84.2 MW), Eggebek Solar Park (Germany 83.6 MW), Senftenberg Solarpark (Germany 82 MW), Finsterwalde Solar Park (Germany, 80.7 MW), Okhotnykovo Solar Park (Ukraine, 80 MW), Lopburi Solar Farm (Thailand 73.16 MW), Rovigo Photovoltaic Power Plant (Italy, 72 MW), and the Lieberose Photovoltaic Park (Germany, 71.8 MW).
There are also many large plants under construction. The Desert Sunlight Solar Farm under construction in Riverside County, California and Topaz Solar Farm being built in San Luis Obispo County, California are both 550 MW solar parks that will use thin-film solar photovoltaic modules made by First Solar. The Blythe Solar Power Project is a 500 MW photovoltaic station under construction in Riverside County, California. The California Valley Solar Ranch (CVSR) is a 250 megawatt (MW) solar photovoltaic power plant, which is being built by SunPower in the Carrizo Plain, northeast of California Valley. The 230 MW Antelope Valley Solar Ranch is a First Solar photovoltaic project which is under construction in the Antelope Valley area of the Western Mojave Desert, and due to be completed in 2013. The Mesquite Solar project is a photovoltaic solar power plant being built in Arlington, Maricopa County, Arizona, owned by Sempra Generation. Phase 1 will have a nameplate capacity of 150 megawatts.
Many of these plants are integrated with agriculture and some use innovative tracking systems that follow the sun's daily path across the sky to generate more electricity than conventional fixed-mounted systems. There are no fuel costs or emissions during operation of the power stations.
Wind power 
Some of the second-generation renewables, such as wind power, have high potential and have already realised relatively low production costs. Global wind power installations increased by 35,800 MW in 2010, bringing total installed capacity up to 194,400 MW, a 22.5% increase on the 158,700 MW installed at the end of 2009. The increase for 2010 represents investments totalling €47.3 billion (US$65 billion) and for the first time more than half of all new wind power was added outside of the traditional markets of Europe and North America, mainly driven, by the continuing boom in China which accounted for nearly half of all of the installations at 16,500 MW. China now has 42,300 MW of wind power installed. Wind power accounts for approximately 19% of electricity generated in Denmark, 9% in Spain and Portugal, and 6% in Germany and the Republic of Ireland. These are some of the largest wind farms in the world, as of 2012:
|Alta (Oak Creek-Mojave)||1,320||United States|||
|Buffalo Gap Wind Farm||523.3||United States|||
|Capricorn Ridge Wind Farm||662.5||United States|||
|Cedar Creek Wind Farm||551||United States|
|Dabancheng Wind Farm||500||People's Republic of China|||
|Fântânele-Cogealac Wind Farm||600||Romania|||
|Fowler Ridge Wind Farm||599.8||United States|||
|Horse Hollow Wind Energy Center||735.5||United States|||
|Jaisalmer Wind Park||1,064||India|||
|Meadow Lake Wind Farm||500||United States|||
|Roscoe Wind Farm||781.5||United States|||
|Shepherds Flat Wind Farm||845||United States|
|Sweetwater Wind Farm||585.3||United States|||
There are many large wind farms under construction and these include Anholt Offshore Wind Farm (400 MW), BARD Offshore 1 (400 MW), Clyde Wind Farm (548 MW), Fântânele-Cogealac Wind Farm (600 MW), Greater Gabbard wind farm (500 MW), Lincs Wind Farm (270 MW), London Array (1000 MW), Lower Snake River Wind Project (343 MW), Shepherds Flat Wind Farm (845 MW), Sheringham Shoal (317 MW), and the Walney Wind Farm (367 MW).
Solar thermal power stations 
Solar thermal power stations include the 354 megawatt (MW) Solar Energy Generating Systems power plant in the USA, Solnova Solar Power Station (Spain, 150 MW), Andasol solar power station (Spain, 100 MW), Nevada Solar One (USA, 64 MW), PS20 solar power tower (Spain, 20 MW), and the PS10 solar power tower (Spain, 11 MW). The 370 MW Ivanpah Solar Power Facility, located in California's Mojave Desert, is the world's largest solar-thermal power plant project currently under construction. Many other plants are under construction or planned, mainly in Spain and the USA. In developing countries, three World Bank projects for integrated solar thermal/combined-cycle gas-turbine power plants in Egypt, Mexico, and Morocco have been approved.
Modern forms of Bioenergy 
Global ethanol production for transport fuel tripled between 2000 and 2007 from 17 billion to more than 52 billion litres, while biodiesel expanded more than tenfold from less than 1 billion to almost 11 billion litres. Biofuels provide 1.8% of the world's transport fuel and recent estimates indicate a continued high growth. The main producing countries for transport biofuels are the USA, Brazil, and the EU.
Brazil has one of the largest renewable energy programs in the world, involving production of ethanol fuel from sugar cane, and ethanol now provides 18 percent of the country's automotive fuel. As a result of this and the exploitation of domestic deep water oil sources, Brazil, which for years had to import a large share of the petroleum needed for domestic consumption, recently reached complete self-sufficiency in liquid fuels.
Nearly all the gasoline sold in the United States today is mixed with 10 percent ethanol, a mix known as E10, and motor vehicle manufacturers already produce vehicles designed to run on much higher ethanol blends. Ford, DaimlerChrysler, and GM are among the automobile companies that sell flexible-fuel cars, trucks, and minivans that can use gasoline and ethanol blends ranging from pure gasoline up to 85% ethanol (E85). The challenge is to expand the market for biofuels beyond the farm states where they have been most popular to date. The Energy Policy Act of 2005, which calls for 7.5 billion US gallons (28,000,000 m3) of biofuels to be used annually by 2012, will also help to expand the market.
The growing ethanol and biodiesel industries are providing jobs in plant construction, operations, and maintenance, mostly in rural communities. According to the Renewable Fuels Association, "the ethanol industry created almost 154,000 U.S. jobs in 2005 alone, boosting household income by $5.7 billion. It also contributed about $3.5 billion in tax revenues at the local, state, and federal levels".
Third-generation technologies 
Third-generation renewable energy technologies are still under development and include advanced biomass gasification, biorefinery technologies, hot-dry-rock geothermal power, and ocean energy. Third-generation technologies are not yet widely demonstrated or have limited commercialization. Many are on the horizon and may have potential comparable to other renewable energy technologies, but still depend on attracting sufficient attention and research and development funding.
New bioenergy technologies 
|Abengoa Bioenergy||Hugoton, KS||Wheat straw|
|BlueFire Ethanol||Irvine, CA||Multiple sources|
|Gulf Coast Energy||Mossy Head, FL||Wood waste|
|POET LLC||Emmetsburg, IA||Corn cobs|
|SunOpta||Little Falls, MN||Wood chips|
|Xethanol||Auburndale, FL||Citrus peels|
According to the International Energy Agency, cellulosic ethanol biorefineries could allow biofuels to play a much bigger role in the future than organizations such as the IEA previously thought. Cellulosic ethanol can be made from plant matter composed primarily of inedible cellulose fibers that form the stems and branches of most plants. Crop residues (such as corn stalks, wheat straw and rice straw), wood waste, and municipal solid waste are potential sources of cellulosic biomass. Dedicated energy crops, such as switchgrass, are also promising cellulose sources that can be sustainably produced in many regions.
Ocean energy 
Ocean energy is all forms of renewable energy derived from the sea including wave energy, tidal energy, river current, ocean current energy, offshore wind, salinity gradient energy and ocean thermal gradient energy.
Tidal Power 
The Rance Tidal Power Station (240 MW) is the world's first tidal power station. The facility is located on the estuary of the Rance River, in Brittany, France. Opened on the 26th November 1966, it is currently operated by Électricité de France, and is the largest tidal power station in the world, in terms of installed capacity.
Wave Power 
First proposed more than thirty years ago, systems to harvest utility-scale electrical power from ocean waves have recently been gaining momentum as a viable technology. The potential for this technology is considered promising, especially on west-facing coasts with latitudes between 40 and 60 degrees:
In the United Kingdom, for example, the Carbon Trust recently estimated the extent of the economically viable offshore resource at 55 TWh per year, about 14% of current national demand. Across Europe, the technologically achievable resource has been estimated to be at least 280 TWh per year. In 2003, the U.S. Electric Power Research Institute (EPRI) estimated the viable resource in the United States at 255 TWh per year (6% of demand).
There are currently nine projects, completed or in-development, off the coasts of the United Kingdom, United States, Spain and Australia to harness the rise and fall of waves by Ocean Power Technologies. The current maximum power output is 1.5 MW (Reedsport, Oregon), with development underway for 100 MW (Coos Bay, Oregon).
Enhanced geothermal systems 
As of 2008[update], geothermal power development was under way in more than 40 countries, partially attributable to the development of new technologies, such as Enhanced Geothermal Systems. The development of binary cycle power plants and improvements in drilling and extraction technology may enable enhanced geothermal systems over a much greater geographical range than "traditional" Geothermal systems. Demonstration EGS projects are operational in the USA, Australia, Germany, France, and The United Kingdom.
Renewable energy industry 
Total investment in renewable energy reached $211 billion in 2010, up from $160 billion in 2009. The top countries for investment in 2010 were China, Germany, the United States, Italy, and Brazil. Continued growth for the renewable energy sector is expected and promotional policies helped the industry weather the 2009 economic crisis better than many other sectors.
Wind power companies 
As of 2010[update], Vestas (from Denmark) is the world's top wind turbine manufacturer in terms of percentage of market volume, and Sinovel (from China) is in second place. Together Vestas and Sinovel delivered 10,228 MW of new wind power capacity in 2010, and their market share was 25.9 percent. GE Energy (USA) was in third place, closely followed by Goldwind, another Chinese supplier. German Enercon ranks fifth in the world, and is followed in sixth place by Indian-based Suzlon.
Photovoltaic companies 
The solar PV market has been growing for the past few years. According to solar PV research company, PVinsights, worldwide shipment of solar modules in 2011 was around 25 GW, and the shipment year over year growth was around 40%. The top 5 solar module players in 2011 in turns are Suntech, First Solar, Yingli, Trina, and Canadian. The top 5 solar module companies possessed 51.3% market share of solar modules, according to PVinsights' market intelligence report.
|2011 Ranking||Marketshare||Solar Module Company||2010 ranking||Marketshare||Country|
|8||2.7%||Hanwha Solarone||7||||South Korea|
Non-technical barriers to acceptance 
Current energy markets, institutions, and policies have been developed to support the production and use of fossil fuels. Newer and cleaner technologies may offer social and environmental benefits, but utility operators often reject renewable resources because they are trained to think only in terms of big, conventional power plants. Consumers often ignore renewable power systems because they are not given accurate price signals about electricity consumption. Intentional market distortions (such as subsidies), and unintentional market distortions (such as split incentives) may work against renewables. Benjamin K. Sovacool has argued that "some of the most surreptitious, yet powerful, impediments facing renewable energy and energy efficiency in the United States are more about culture and institutions than engineering and science".
The obstacles to the widespread commercialization of renewable energy technologies are primarily political, not technical, and there have been many studies which have identified a range of "non-technical barriers" to renewable energy use. These barriers are impediments which put renewable energy at a marketing, institutional, or policy disadvantage relative to other forms of energy. Key barriers include:
- Difficulty overcoming established energy systems, which includes difficulty introducing innovative energy systems, particularly for distributed generation such as photovoltaics, because of technological lock-in, electricity markets designed for centralized power plants, and market control by established operators. As the Stern Review on the Economics of Climate Change points out:
- National grids are usually tailored towards the operation of centralised power plants and thus favour their performance. Technologies that do not easily fit into these networks may struggle to enter the market, even if the technology itself is commercially viable. This applies to distributed generation as most grids are not suited to receive electricity from many small sources. Large-scale renewables may also encounter problems if they are sited in areas far from existing grids.
- Lack of government policy support, which includes the lack of policies and regulations supporting deployment of renewable energy technologies and the presence of policies and regulations hindering renewable energy development and supporting conventional energy development. Examples include subsidies for fossil-fuels, insufficient consumer-based renewable energy incentives, government underwriting for nuclear plant accidents, and complex zoning and permitting processes for renewable energy.
- Lack of information dissemination and consumer awareness.
- Higher capital cost of renewable energy technologies compared with conventional energy technologies.
- Inadequate financing options for renewable energy projects, including insufficient access to affordable financing for project developers, entrepreneurs and consumers.
- Imperfect capital markets, which includes failure to internalize all costs of conventional energy (e.g., effects of air pollution, risk of supply disruption) and failure to internalize all benefits of renewable energy (e.g., cleaner air, energy security).
- Inadequate workforce skills and training, which includes lack of adequate scientific, technical, and manufacturing skills required for renewable energy production; lack of reliable installation, maintenance, and inspection services; and failure of the educational system to provide adequate training in new technologies.
- Lack of adequate codes, standards, utility interconnection, and net-metering guidelines.
- Poor public perception of renewable energy system aesthetics.
- Lack of stakeholder/community participation and co-operation in energy choices and renewable energy projects.
With such a wide range of non-technical barriers, there is no "silver bullet" solution to drive the transition to renewable energy. So ideally there is a need for several different types of policy instruments to complement each other and overcome different types of barriers.
A policy framework must be created that will level the playing field and redress the imbalance of traditional approaches associated with fossil fuels. The policy landscape must keep pace with broad trends within the energy sector, as well as reflecting specific social, economic and environmental priorities.
Public policy landscape 
Public policy has a role to play in renewable energy commercialization because the free market system has some fundamental limitations. As the Stern Review points out:
In a liberalised energy market, investors, operators and consumers should face the full cost of their decisions. But this is not the case in many economies or energy sectors. Many policies distort the market in favour of existing fossil fuel technologies.
The International Solar Energy Society has stated that "historical incentives for the conventional energy resources continue even today to bias markets by burying many of the real societal costs of their use".
Fossil-fuel energy systems have different production, transmission, and end-use costs and characteristics than do renewable energy systems, and new promotional policies are needed to ensure that renewable systems develop as quickly and broadly as is socially desirable.
Lester Brown states that the market "does not incorporate the indirect costs of providing goods or services into prices, it does not value nature's services adequately, and it does not respect the sustainable-yield thresholds of natural systems". It also favors the near term over the long term, thereby showing limited concern for future generations. Tax and subsidy shifting can help overcome these problems.
Shifting taxes 
Tax shifting has been widely discussed and endorsed by economists. It involves lowering income taxes while raising levies on environmentally destructive activities, in order to create a more responsive market. For example, a tax on coal that included the increased health care costs associated with breathing polluted air, the costs of acid rain damage, and the costs of climate disruption would encourage investment in renewable technologies. Several Western European countries are already shifting taxes in a process known there as environmental tax reform.
A four-year plan adopted in Germany in 1999 gradually shifted taxes from labor to energy and, by 2001, this plan had lowered fuel use by 5 percent. It had also increased renewable energy sector growth, creating some 45,400 jobs by 2003 in the wind power industry alone, a number that is projected to rise to 103,000 by 2010. In 2001, Sweden launched a new 10-year environmental tax shift designed to convert 30 billion kroner ($3.9 billion) of income taxes to taxes on environmentally destructive activities. Other European countries with significant tax reform efforts are France, Italy, Norway, Spain, and the United Kingdom. Asia's two leading economies, Japan and China, are considering carbon taxes.
Shifting subsidies 
Just as there is a need for tax shifting, there is also a need for subsidy shifting. Subsidies are not an inherently bad thing as many technologies and industries emerged through government subsidy schemes. The Stern Review explains that of 20 key innovations from the past 30 years, only one of the 14 was funded entirely by the private sector and nine were totally publicly funded. In terms of specific examples, the Internet was the result of publicly funded links among computers in government laboratories and research institutes. And the combination of the federal tax deduction and a robust state tax deduction in California helped to create the modern wind power industry.
Lester Brown has argued that "a world facing the prospect of economically disruptive climate change can no longer justify subsidies to expand the burning of coal and oil. Shifting these subsidies to the development of climate-benign energy sources such as wind, solar, biomass, and geothermal power is the key to stabilizing the earth's climate." The International Solar Energy Society advocates "leveling the playing field" by redressing the continuing inequities in public subsidies of energy technologies and R&D, in which the fossil fuel and nuclear power receive the largest share of financial support.
Some countries are eliminating or reducing climate disrupting subsidies and Belgium, France, and Japan have phased out all subsidies for coal. Germany is reducing its coal subsidy. The subsidy dropped from $5.4 billion in 1989 to $2.8 billion in 2002, and in the process Germany lowered its coal use by 46 percent. China cut its coal subsidy from $750 million in 1993 to $240 million in 1995 and more recently has imposed a high-sulfur coal tax. However, the United States has been increasing its support for the fossil fuel and nuclear industries.
In November 2011, an IEA report entitled Deploying Renewables 2011 said "subsidies in green energy technologies that were not yet competitive are justified in order to give an incentive to investing into technologies with clear environmental and energy security benefits". The IEA's report disagreed with claims that renewable energy technologies are only viable through costly subsidies and not able to produce energy reliably to meet demand.
Renewable energy targets 
Setting national renewable energy targets can be an important part of a renewable energy policy and these targets are usually defined as a percentage of the primary energy and/or electricity generation mix. For example, the European Union has prescribed an indicative renewable energy target of 12 per cent of the total EU energy mix and 22 per cent of electricity consumption by 2010. National targets for individual EU Member States have also been set to meet the overall target. Other developed countries with defined national or regional targets include Australia, Canada, Israel, Japan, Korea, New Zealand, Norway, Singapore, Switzerland, and some US States.
National targets are also an important component of renewable energy strategies in some developing countries. Developing countries with renewable energy targets include China, India, Indonesia, Malaysia, the Philippines, Thailand, Brazil, Egypt, Mali, and South Africa. The targets set by many developing countries are quite modest when compared with those in some industrialized countries.
Renewable energy targets in most countries are indicative and nonbinding but they have assisted government actions and regulatory frameworks. The United Nations Environment Program has suggested that making renewable energy targets legally binding could be an important policy tool to achieve higher renewable energy market penetration.
Levelling the playing field 
The IEA has identified three actions which will allow renewable energy and other clean energy technologies to "more effectively compete for private sector capital":
- "First, energy prices must appropriately reflect the "true cost" of energy (e.g. through carbon pricing) so that the positive and negative impacts of energy production and consumption are fully taken into account".
- "Second, inefficient fossil fuel subsidies must be removed, while ensuring that all citizens have access to affordable energy".
- "Third, governments must develop policy frameworks that encourage private sector investment in lower-carbon energy options".
Green stimulus programs 
In response to the global financial crisis in the late 2000s, the world's major governments made "green stimulus" programs one of their main policy instruments for supporting economic recovery. Some US$188 billion in green stimulus funding had been allocated to renewable energy and energy efficiency, to be spent mainly in 2010 and in 2011.
Voluntary market mechanisms for renewable electricity 
Voluntary markets, also referred to as green power markets, are driven by consumer preference. Voluntary markets allow a consumer to choose to do more than policy decisions require and reduce the environmental impact of their electricity use. Voluntary green power products must offer a significant benefit and value to buyers to be successful. Benefits may include zero or reduced greenhouse gas emissions, other pollution reductions or other environmental improvements on power stations. 
The driving force behind voluntary green electricity within the EU are the liberalized electricity markets and the RES Directive. According to the directive the EU Member States must ensure that the origin of electricity produced from renewables can be guaranteed and therefore a “guarantee of origin” must be issued (article 15).
Environmental organisations are using the voluntary market to create new renewables and improving sustainability of the existing power production. In the US the main tool to track and stimulate voluntary actions is Green-e program managed by Center for Resource Solutions.
Recent developments 
A number of events in 2006 pushed renewable energy up the political agenda, including the US mid-term elections in November, which confirmed clean energy as a mainstream issue. Also in 2006, the Stern Review made a strong economic case for investing in low carbon technologies now, and argued that economic growth need not be incompatible with cutting energy consumption. According to a trend analysis from the United Nations Environment Programme, climate change concerns coupled with recent high oil prices and increasing government support are driving increasing rates of investment in the renewable energy and energy efficiency industries.
Investment capital flowing into renewable energy reached a record US$77 billion in 2007, with the upward trend continuing in 2008. The OECD still dominates, but there is now increasing activity from companies in China, India and Brazil. Chinese companies were the second largest recipient of venture capital in 2006 after the United States. In the same year, India was the largest net buyer of companies abroad, mainly in the more established European markets.
New government spending, regulation, and policies helped the industry weather the 2009 economic crisis better than many other sectors. Most notably, U.S. President Barack Obama's American Recovery and Reinvestment Act of 2009 included more than $70 billion in direct spending and tax credits for clean energy and associated transportation programs. This policy-stimulus combination represents the largest federal commitment in U.S. history for renewables, advanced transportation, and energy conservation initiatives. Based on these new rules, many more utilities strengthened their clean-energy programs. Clean Edge suggests that the commercialization of clean energy will help countries around the world deal with the current economic malaise.
Once-promising solar energy company, Solyndra, became involved in a political controversy involving U.S. President Barack Obama's administration's authorization of a $535 million loan guarantee to the Corporation in 2009 as part of a program to promote alternative energy growth. The company ceased all business activity, filed for Chapter 11 bankruptcy, and laid-off nearly all of its employees in early September 2011. Critics claimed that the Obama administration may have unduly influenced the loan. 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". 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".
In his January 24, 2012, State of the Union address, President Barack Obama restated his commitment to renewable energy. Obama said that he "will not walk away from the promise of clean energy." Obama called for a commitment by the Defense Department to purchase 1,000 MW of renewable energy. He also mentioned the long-standing Interior Department commitment to permit 10,000 MW of renewable energy projects on public land in 2012.
100% renewable energy 
The incentive to use 100% renewable energy is created by global warming and ecological as well as economic concerns, post peak oil. The first country to propose 100% renewable energy was Iceland, in 1998. Proposals have been made for Japan in 2003, and for Australia in 2011. Norway and some other countries already obtain all of their electricity from renewable sources.
A 2009 study suggests that converting the entire world to 100% renewable energy by 2030 is both possible and affordable, but requires political support. It would require building many more wind turbines and solar power systems. Other changes involve use of electric cars and the development of enhanced transmission grids and storage.
Vision 2050 for Europe set a 2050 timeline for converting to 100% renewable energy, later reduced to 2040 in 2011. Zero Carbon Britain 2030 proposes eliminating carbon emissions in Britain by 2030 by transitioning to renewable energy.
In 2011, the refereed journal Energy Policy published two articles by Mark Z. Jacobson, a professor of engineering at Stanford University, and Mark A. Delucchi, about changing our energy supply mix and "Providing all global energy with wind, water, and solar power". The articles analyze the feasibility of providing worldwide energy for electric power, transportation, and heating/cooling from wind, water, and sunlight (WWS), which are safe clean options. The authors advocate producing all new energy with WWS by 2030 and replacing existing energy supply arrangements by 2050. Barriers to implementing the renewable energy plan are seen to be "primarily social and political, not technological or economic". Energy costs with a WWS system should be similar to today's energy costs.
A 2012 study by the University of Delaware for a 72 GW system considered 28 billion combinations of renewable energy and storage and found the most cost effective, for the PJM Interconnection, would use 17 GW of solar, 68 GW of offshore wind, and 115 GW of onshore wind, although at times as much as three times the demand would be provided. 0.1% of the time would require generation from other sources.
Sustainable energy 
Moving towards energy sustainability will require changes not only in the way energy is supplied, but in the way it is used, and reducing the amount of energy required to deliver various goods or services is essential. Opportunities for improvement on the demand side of the energy equation are as rich and diverse as those on the supply side, and often offer significant economic benefits.
A sustainable energy economy requires commitments to both renewables and efficiency. Renewable energy and energy efficiency are said to be the "twin pillars" of sustainable energy policy. The American Council for an Energy-Efficient Economy has explained that both resources must be developed in order to stabilize and reduce carbon dioxide emissions:
Efficiency is essential to slowing the energy demand growth so that rising clean energy supplies can make deep cuts in fossil fuel use. If energy use grows too fast, renewable energy development will chase a receding target. Likewise, unless clean energy supplies come online rapidly, slowing demand growth will only begin to reduce total emissions; reducing the carbon content of energy sources is also needed.
The IEA has stated that renewable energy and energy efficiency policies are complementary tools for the development of a sustainable energy future, and should be developed together instead of being developed in isolation.
See also 
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- Cost of electricity by source
- Energy security and renewable technology
- Environmental tariff
- Feed-in Tariff
- International Renewable Energy Agency
- PV financial incentives
- Rocky Mountain Institute
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