Green energy

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A solar trough array is an example of green energy

Green energy is the term used to describe sources of energy that are considered to be environmentally friendly and non-polluting, such as geothermal, wind, solar, and hydro [1][2][3][4]. Sometimes nuclear power is also considered a green energy source. [5][6][7][8][9] Green energy sources are often considered "green" because they are perceived to lower carbon emissions and create less pollution.

Green energy is commonly thought of in the context of electricity, mechanical power, heating and cogeneration. Consumers, businesses, and organizations may purchase green energy in order to support further development, help reduce the environmental impacts of conventional electricity generation, and increase their nation’s energy independence. Renewable energy certificates (Green certificates or green tags) have been one way for consumers and businesses to support green energy.


[edit] Related terms

In the media, Green energy is often used interchangeably with the term Renewable energy.[10][11][12] Alternative energy and clean technologies are other terms often used instead of renewable energy. The terms suggest a non-polluting, non-fossil-fuel source. Green power is sometimes used in reference to electricity generated from "green" sources.[13] Brown energy is sometimes used to contrast non-renewable or polluting energy sources with green energy.[14]

[edit] Green sources

A wind turbine at Greenpark, Reading, England, generating green electricity for approx 1000 homes.

Green energy includes natural energetic processes that can be harnessed with little pollution. Anaerobic digestion, geothermal power, wind power, small-scale hydropower, solar energy, biomass power, tidal power, and wave power fall under such a category. Some definitions may also include power derived from the incineration of waste.

Some organizations have specifically classified nuclear power as green energy[15], but environmental organizations indicate the problems with nuclear waste and claim that this energy is neither efficient nor effective in cutting CO2 emissions, excluding it from clean energy [16] .

No power source is entirely impact-free. All energy sources require energy and give rise to some degree of pollution from manufacture of the technology.

[edit] Comparison to non-green sources

The Vattenfall study found Nuclear, Hydro, and Wind to have far less greenhouse emissions than other sources represented.

The Swedish utility Vattenfall did a study of full life cycle emissions of Nuclear, Hydro, Coal, Gas, Solar Cell, Peat and Wind which the utility uses to produce electricity. The net result of the study was that nuclear power produced 3.3 grams of carbon dioxide per KW-Hr of produced power. This compares to 400 for natural gas and 700 for coal (according to this study). The study also concluded that nuclear power produced the smallest amount of CO2 of any of their electricity sources. [17]

Claims exist that the problems of nuclear waste do not come anywhere close to approaching the problems of fossil fuel waste.[18][19] A 2004 article from the BBC states: "The World Health Organization (WHO) says 3 million people are killed worldwide by outdoor air pollution annually from vehicles and industrial emissions, and 1.6 million indoors through using solid fuel."[20] In the U.S. alone, fossil fuel waste kills 20,000 people each year.[21] A coal power plant releases 100 times as much radiation as a nuclear power plant of the same wattage.[22] It is estimated that during 1982, US coal burning released 155 times as much radioactivity into the atmosphere as the Three Mile Island incident.[23] In addition, fossil fuel waste causes global warming, which leads to increased deaths from hurricanes, flooding, and other weather events. The World Nuclear Association provides a comparison of deaths due to accidents among different forms of energy production. In their comparison, deaths per TW-yr of electricity produced from 1970 to 1992 are quoted as 885 for hydropower, 342 for coal, 85 for natural gas, and 8 for nuclear.[24]

[edit] Purchasing green energy through the electrical grid

In several countries with common carrier arrangements, electricity retailing arrangements make it possible for consumers to purchase green electricity (renewable electricity) from either their utility or a green power provider.

When energy is purchased from the electricity network, the power reaching the consumer will not necessarily be generated from green energy sources. The local utility company, electric company, or state power pool buys their electricity from electricity producers who may be generating from fossil fuel, nuclear or renewable energy sources. In many countries green energy currently provides a very small amount of electricity, generally contributing less than 2 to 5% to the overall pool. In some U.S. states, local governments have formed regional power purchasing pools using [Community Choice Aggregation] and [Solar Bonds] to achieve a 51% renewable mix or higher, such as in the City of San Francisco.[25]

By participating in a green energy program a consumer may be having an effect on the energy sources used and ultimately might be helping to promote and expand the use of green energy. They are also making a statement to policy makers that they are willing to pay a price premium to support renewable energy. Green energy consumers either obligate the utility companies to increase the amount of green energy that they purchase from the pool (so decreasing the amount of non-green energy they purchase), or directly fund the green energy through a green power provider. If insufficient green energy sources are available, the utility must develop new ones or contract with a third party energy supplier to provide green energy, causing more to be built. However, there is no way the consumer can check whether or not the electricity bought is "green" or otherwise.

In some countries such as the Netherlands, electricity companies guarantee to buy an equal amount of 'green power' as is being used by their green power customers. The Dutch government exempts green power from pollution taxes, which means green power is hardly any more expensive than other power.

In the United States, one of the main problems with purchasing green energy through the electrical grid is the current centralized infrastructure that supplies the consumer’s electricity. This infrastructure has lead to increasingly frequent brown outs and black outs, high CO2 emissions, higher energy costs, and power quality issues [26]. An additional $450 billion will be invested to expand this fledgling system over the next 20 years in order to meet increasing demand [27]. In addition, this centralized system is now being further overtaxed with the incorporation of renewable energies such as wind, solar, and geothermal energies. Renewable resources, due to the amount of space they require, are often located in remote areas where there is a lower energy demand. The current infrastructure would make transporting this energy to high demand areas, such as urban centers, highly inefficient and in some cases impossible. In addition, despite the amount of renewable energy produced or the economic viability of such technologies only about 20 percent will be able to be incorporated into the grid. In order to have a more sustainable energy profile, the United States has to move towards implementing changes to the electrical grid that will accommodate a mixed-fuel economy [28].

However, several initiatives are being proposed to mitigate these distribution problems. First and foremost, the most effective way to reduce USA’s CO2 emissions and slow global warming is through conservation efforts. Opponents of the current US electrical grid have also advocated for decentralizing the grid. This system would increase efficiency by reducing the amount of energy lost in transmission. It would also be economically viable as it would reduce the amount of power lines that will need to be constructed in the future to keep up with demand. Merging heat and power in this system would create added benefits and help to increase its efficiency by up to 80-90%. This is a significant increase from the current fossil fuel plants which only have an efficiency of 34% [29].

A more recent concept for improving our electrical grid is to beam microwaves from Earth-orbiting satellites or the moon to directly when and where there is demand. The power would be generated from solar energy captured on the lunar surface In this system, the receivers would be “broad, translucent tent-like structures that would receive microwaves and convert them to electricity”. NASA said in 2000 that the technology was worth pursuing but it is still too soon to say if the technology will be cost-effective [30].

[edit] Abuses

In countries where suppliers are legally obliged to purchase a proportion of their electricity from renewable sources (for example under the Renewables Obligation in the United Kingdom), there is a danger that energy suppliers may sell such green electricity under a premium "green energy" tariff, rather than sourcing additional green electricity supplies.[31] Where a Renewable Energy Certificate or similar scheme is in operation it is also possible for the energy supplier to sell the green electricity to the consumer, and also sell the certificate to another supplier who has failed to meet their quota, rather than "retiring" the certificate from the marketplace. In other cases green energy tariffs may involve carbon offsetting rather than purchasing or investing in renewable energy.[32][33]

Certification schemes to minimise these and similar questionable practices are in place or are being developed in a few countries.[34]

[edit] International standards

The World Wide Fund for Nature and several green electricity labelling organizations have created the Eugene Green Energy Standard under which the national green electricity certification schemes can be accredited to ensure that the purchase of green energy leads to the provision of additional new green energy resources.[35]

[edit] Purchasing green energy through the gas grid

The market for heating is mostly serviced by gas and oil rather than electric power, due to the high cost per kilowatt of electricity in many countries.[citation needed] Distribution of renewable electric power via the electrical grid has made it possible in many countries for consumers to choose renewable electric power, and in the same manner bionatural gas may in the future be made available to the average consumer via the existing natural gas grid.[36][37]

[edit] Local green energy systems

Those not satisfied with the third-party grid approach to green energy via the power grid can install their own locally-based renewable energy system. Renewable energy electrical systems from solar to wind to even local hydro-power in some cases, are some of the many types of renewable energy systems available locally. Additionally, for those interested in heating and cooling their dwelling via renewable energy, geothermal heat pump systems that tap the constant temperature of the earth, which is around 7 to 15 degrees Celsius a few feet underground, are an option and save money over conventional natural gas and petroleum-fueled heat approaches.

[edit] United States

The advantage of this approach in the United States is that many states offer incentives to offset the cost of installation of a renewable energy system. In California, Massachusetts and several other U.S. states, a new approach to community energy supply called [Community Choice Aggregation] has provided communities with the means to solicit a competitive electricity supplier and use municipal revenue bonds to finance development of local green energy resources. Individuals are usually assured that the electricity they are using is actually produced from a green energy source that they control. Once the system is paid for, the owner of a renewable energy system will be producing their own renewable electricity for essentially no cost and can sell the excess to the local utility at a profit.

[edit] Green energy and labelling by region

[edit] European Union

Directive 2004/8/EC of the European Parliament and of the Council of 11 February 2004 on the promotion of cogeneration based on a useful heat demand in the internal energy market[38] includes the article 5 (Guarantee of origin of electricity from high-efficiency cogeneration).

[edit] United Kingdom

See Green electricity in the United Kingdom for further information.

[edit] France

Nuclear power gives France the cleanest air of any indusrtrialized country in the world. [39]      thermofossil      hydroelectric      nuclear      Other renewables

Over 75% of french electricity comes from nuclear power plants.[40] [41] France is the largest net exporter of electricity in the world.[40] Electricity exports generate over 3 billion euros of revenue a year for France.[40] French electricity costs are among the lowest in Europe.[40] A major factor in the low cost of electricity in France is the use of a single reactor design, which allows for economies of scale.[41] French CO2 emissions are among the lowest in the developed world, with 10 tons of CO2 equivalents per person per year.[42] Danish citizens emit an average of 14 tons of CO2 equivalents per person per year.[43] Even Iceland, with its abundance of geothermal energy for heating, has higher per Capita emissions at 10.4 tons of CO2 equivalents per Capita.[44]

[edit] Spain

In Spain green energy is regulated by the Orden ITC/1522/2007.[45]

[edit] Portugal

José Sócrates, the Portuguese Prime-minister said that Portugal is to become one of the largest producers and users of this type of energy in Europe by 2010, and that Portugal has a great potential to produce solar, water, waves, geothermic and wind energies.[citation needed]

[edit] United States

The United States Department of Energy (DOE), the Environmental Protection Agency (EPA), and the Center for Resource Solutions (CRS)[46] recognizes the voluntary purchase of electricity from renewable energy sources (also called renewable electricity or green electricity) as green power.

DOE selected six companies for its 2007 Green Power Supplier Awards, including Constellation NewEnergy; 3Degrees; Sterling Planet; SunEdison; Pacific Power and Rocky Mountain Power; and Silicon Valley Power. The combined green power provided by those six winners equals more than 5 billion kilowatt-hours per year, which is enough to power nearly 465,000 average U.S. households.

The EPA recognized the West Division of Macy's Inc., The Timberland Company, and the City of Chico, California, for their on-site generation of solar power, and also recognized New York University and six companies for purchasing green power. The EPA also named the city of Bellingham, Washington, and six more companies as their Green Power Partners of the Year. Among all the companies, PepsiCo stands out as a partner of the year, because three of its bottling companies were also honored for buying green power. In addition, CRS awarded its Market Development Awards to the Western Washington Green Power Campaign, Clif Bar, and two individuals: John Schaeffer and Bill Spratley.

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.

[edit] Oceania & Pacific

[edit] Australia

See Green electricity in Australia for further information

[edit] See also

[edit] National articles

[edit] References

  1. ^ TransACT
  2. ^ "Buzz terms in the eco sphere" (The Hindu Business Line)
  3. ^
  4. ^ The Energy Institute
  5. ^ Going Nuclear: A Green Makes the Case, The Washington Post, April 16, 2006
  6. ^ France closes its last coal mine, BBC, April 23, 2004
  7. ^ France: Vive Les Nukes, "60 Minutes," CBS, April 8, 2007
  8. ^ Hot idea: Fight warming with nuclear power, MSNBC, July 7, 2005
  9. ^ Environmentalists For Nuclear Energy
  10. ^ [1]
  11. ^ [2]
  12. ^ [3]
  13. ^ "Green Power Defined". United States Evnironmental Protection Agency. Retrieved on 2008-03-10. 
  14. ^ Renewable Energy, by Professor John Twidell
  15. ^ Nuclear power is particularly green energy: get used to it |
  16. ^ WISE - Nuclear issues information service
  17. ^ Greenhouse Emissions of Nuclear Power
  18. ^ David Bodansky. "The Environmental Paradox of Nuclear Power". American Physical Society. Retrieved on 2008-01-31. "(reprinted from Environmental Practice, vol. 3, no. 2 (June 2001), pp.86–88 {Oxford University Press))" 
  19. ^ "Some Amazing Facts about Nuclear Power". August 2002. Retrieved on 2008-01-31. 
  20. ^ Alex Kirby (13 December 2004,). ""Pollution: A life and death issue"". BBC News. Retrieved on 2008-01-31. 
  21. ^ Don Hopey (June 29, 2005). ""State sues utility for U.S. pollution violations"". Pittsburgh Post-Gazette. Retrieved on 2008-01-31. 
  22. ^ Alex Gabbard. "Coal Combustion: Nuclear Resource or Danger". Oak Ridge National Laboratory. Retrieved on 2008-01-31. 
  23. ^ Nuclear proliferation through coal burning — Gordon J. Aubrecht, II, Ohio State University
  24. ^ "Safety of Nuclear Power Reactors". 
  25. ^ San Francisco Community Choice Program Design, Draft Implementation Plan and H Bond Action Plan, Ordinance 447-07, 2007.
  26. ^ U.S. Department of Energy Office of Electricity Delivery and Energy Reliability.[4]
  27. ^ "Energy Distribution"U.S. Department of Energy Office of Electricity Delivery and Energy Reliability.[5]
  28. ^ [Whittington, H.W. "Electricity generation: Options for reduction in carbon emissions". Philosophical transactions in mathematics, physcial, and engineering sciences. Vol. 360, No. 1797. (Aug. 15, 2002) Published by: The Royal Society]
  29. ^ Romm, Joseph; Levine, Mark; Brown, Marilyn; Peterson, Eric. “A road map for U.S. carbon reductions”. Science, Vol. 279, No. 5351. (Jan. 30, 1998). Washington
  30. ^ [Britt, Robert Roy. “Could Space-Based Power Plants Prevent Blackouts?”. Science. (August 15, 2003)]
  31. ^ Green Electricity... Are you being conned? The Ecologist, published 2005-06-01, accessed 2007-06-07
  32. ^ "Reality or rhetoric? Green tariffs for domestic consumers" (PDF). The National Consumer Council, UK. December 2006. 
  33. ^ GRÁINNE GILMORE (January 6, 2007). "Grey areas with green energy". The Times. 
  34. ^ Green Power labels not yet at full power, Leonardo Energy, published 2007-01-15, accessed 2007-06-07
  35. ^ Eugene Green Energy Standard, Eugene Network, accessed 2007-06-07
  36. ^ Energy Research Centre of the Netherlands 'Heat from Biomass via Synthetic Natural Gas'
  37. ^ Danish Gas Technology Centre 'Sustainable Gas Enters the European Gas Distribution System'
  38. ^
  39. ^ France: Vive Les Nukes, "60 Minutes," CBS, April 8, 2007
  40. ^ a b c d French Nuclear Power: WNA
  41. ^ a b FRONTLINE: nuclear reaction: Why the French Like Nuclear Energy
  42. ^ Globalis - an interactive world map - France - Greenhouse Gas Emissions per Capita
  43. ^ Globalis - an interactive world map - Denmark - Greenhouse Gas Emissions per Capita
  44. ^ Globalis - an interactive world map - Iceland - Greenhouse Gas Emissions per Capita
  45. ^ (Spanish)
  46. ^

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