Renewable Energy
Jump to: Wind; Solar; Biomass; Geothermal; Ocean Powers; or Hydropower
Eventually all energy will be renewable energy; finite resources, such as fossil fuels, by definition, will run out
[1]. However, estimates regarding when finite energy resources will deplete range from a couple decades to a couple millennia. This phenomena has caused some analysts to claim that any attempt at estimating a fixed date regarding finite energy depletion is a ambiguous endeavor [2]. Yet the fact remains that finite, fossil resources contribute to emissions of greenhouse gases, mounting energy prices, instable markets, international conflict, and other economically unfavorable tensions [2-6]. These fossil fuel negatives are coupled with the fact that emerging nations such as India, China, Russia, and Brazil are increasingly demanding more of the world fossil energy supply [7-10]. Thus, whether fossil energy resources will deplete in the coming decades or in hundreds or thousands of years, renewable energy sources must be developed to address issues which threaten to increasingly destabilize domestic and international energy markets and economies on all levels.
Renewable energy sources are those that replenish themselves – the tide, the wind, the sun, and the heat of the Earth
[11]. These renewable resources are widely available around the world. Clearly this is true for solar energy systems and locations with good wind resources which are found in great numbers worldwide. Similarly, roughly half of the nations on earth have significant geothermal resources, and significant biomass fuel supplies could also be produced by nearly all countries on earth [12]. Yet, despite the availability of renewable energy, and despite the recent push for and interest in renewable energy alternatives, alternative energy development grew only 5% from 2004 to 2005. Even with this growth, renewable electric generation, not including hydroelectric, accounted for only 2.3% of total US net generation in 2005 [13]. Hydroelectric resources provide almost 10% of total US net generation – but the renewability of hydropower has recently come under critique and thus many renewable targets do not include hydropower as a renewable energy source [11, 14].
Most analysts agree that non-fossil energy sources cannot make major inroads in energy and electricity markets because of their present lack of economic viability or public acceptance
[15]. Yet, it is also recognized that renewable energy would grow at a considerably faster pace and come to dominate energy markets sooner if federal subsidies which favor fossil fuels and nuclear power were removed or reduced [1, 16]. Indeed, both in industrialized and developing countries, there is a standing question of “how to remove competition-distorting subsidies and of how to promote the wider use of price signals for creating efficient electricity consumption patterns, for combating congestion and reducing local environmental pollution, and so on” [15].
Lowering the cost of electricity from renewable sources is one of the utmost challenges for increased penetration of the sources
[11]. According to the Institute of Electrical and Electronics Engineers – United States of America (IEEE-USA), the largest barrier to renewable energy is the required capital investment, which is generally larger than that required for conventional power plants. The siting of renewable power plants can also be complicated by the site-specific nature of the resource. Examples include the use of renewable resources on protected lands, the relatively large land requirements for solar power systems, or visual concerns related to wind power plants. In addition, while geothermal and biomass power systems can be operated as baseload or intermediate generation sources, the effective use of solar and wind power systems requires accommodation for the intermittent nature of solar and wind resources [12].
The National Rural Electric Cooperative Association (NRECA) argues that for renewables to take better hold in markets, national policy must be reformulated to include appropriate funding for research and development and incentives to utilize renewables on an equable basis
[17]. Indeed, even though use of renewable power technologies is expanding, these technologies are still at the stage where significant advances are likely to result from strong R&D programs. Such advances coupled with lowered manufacturing costs and increased user confidence that results from expanding deployment will ensure a significant role for these technologies in serving future electricity demands [12].
Yet, renewable electricity generation has made some breakthrough in US markets and will continue to grow in the next couple decades. A renewable portfolio standard (RPS) is a policy set by federal or state governments requiring a certain percentage of electricity supplied by generators in that state be derived from various renewable sources. These sources may include wind, solar, geothermal, biomass, wave, tidal, or other renewables (in some cases, hydropower is included, but due to controversy over its renewable nature, some states omit the source from their RPS). Many progressive states have taken initiative to enact their own, state-level RPS requirements. The diversity of programs is astounding: Massachusetts, for example, requires a 4% renewable share by 2009 with a 1% increase thereafter; New York requires 24% renewables by 2013; California requires 20% by 2010; Arizona requires 15% by 2025; and the list goes on. For full, regularly updated information regarding state-level RPS initiatives, see the Database of State Incentives for Renewables & Efficiency (DSIRE), which provides detailed RPS information by state and US territory.
According to a recent report by the Pew Center on Global Climate Change, well over half of the American public now lives in a state in which an RPS is in operation at least one state has such a policy in every region of the nation except the Southeast
[14].
In recent years, many states have begun to differentiate between various sources of renewable electricity, providing special provisions to support certain forms of renewables that have lagged behind others due to high costs
[14]. As the technologies to utilize renewable energy sources evolve, the expense of their use is coming more in line with fossil energy [11].
Qualifying renewable electricity sources differ across nations and states. The most widely accepted definition of renewable electricity includes that produced from wind, photovoltaics, solar thermal, biomass, geothermal, and ocean powers such as tidal and wave. Some states consider hydroelectric power renewable, while others do not include the source in RPS goals
[14]. The National Renewable Energy Laboratory (NREL) provides excellent GIS-based mapping of renewable resources throughout the United States.
The National Rural Electric Cooperative Association identifies electric cooperatives as particularly important entities in furthering the development of renewable energy technologies. Electric cooperatives own and operate some of the nation’s cleanest and most modern generating facilities and continue to develop advanced wind, solar, and biomass systems [18]. Currently, 550 co-ops offer renewable energy options allowing consumers to buy “green power” from solar, wind, hydroelectric, and biomass generation and as a result, electric cooperatives hold a significant share of the green power market in terms of customer participation [18].
For more information on each energy source, see
Wind;
Solar Photovoltaic and Thermal;
Biomass;
Geothermal;
Ocean Powers (Tidal and Wave); or
Hydropower.
References:
1. Smith, Z.A., The Environmental Policy Paradox. 4th ed. 2004, Upper Saddle River, NJ: Prentice Hall.
2. Smil, V., Energy at the Crossroads: Global Perspectives and Uncertainties. 2003, Cambridge, MA: MIT Press.
3. Campbell, C. and J. Laherrere, The End of Cheap Oil. Scientific American, 1998.
4. Laherrere, J. Estimates of Oil Reserves. in EMF/IEA/IEW Meeting. 2001. IIASA, Laxenburg, Australia: IIASA.
5. Deffeyes, K.S., Hubbert's Peak: The Impending World Oil Shortage. 2003, Princeton, NJ: Princeton University Press.
6. Yergin, D., Ensuring Energy Security. Foreign Affairs, 2006. 85(2): p. 69-82.
7. Bleischwitz, R. and K. Fuhrmann, Introduction to the special issue on 'hydrogen' in 'Energy Policy'. Energy Policy, 2006. 34(11): p. 1223-1226.
8. Winebrake, J.J., Hype or Holy Grail? The Future of Hydrogen in Transportation. Strategic Planning for Energy and the Environment, 2002. 22(2): p. 20-34.
9. Hirsch, R.L., R. Bezdek, and R. Wendling, Peaking of World Oil Production and its Mitigation. AIChE Journal, 2006. 52(1): p. 2-8.
10. Noreng, O., Crude Power: Politics and the Oil Market. 2006, London: I.B. Tauris.
11. Chambers, A., Power Primer: A Nontechnical Guide from Generation to End Use. 1999, Tulsa, Oklahoma: PennWell Publishing Company.
12. IEEE-USA. Solar and Other Renewable Energy Technologies. 2002 [cited 2007 8 April].
13. EIA. Electric Power Annual. 2006 [cited 2007 27 March].
14. Rabe, B., Race to the Top: The Expanding Role of US State Renewable Portfolio Standards. 2006, Pew Center on Global Climate Change: Arlington, VA.
15. OECD, Energy: The Next Fifty Years. 1999, Organization for Economic Co-operation and Development: Paris, France.
16. Goldemberg, J. and T. Johansson, Energy as an Instrument for Socio-Economic Development. 1995, United Nations Development Programme: New York, NY.
17. NRECA. Renewable Energy. 2007 [cited 2007 7 April].
18. NRECA, Electric Cooperatives and Alternative Energy: A Snapshot. 2007, The National Rural Electric Cooperative Association.
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