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Chapter 7 - Energy Resources and Potentials
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- By Hans-Holger Rogner, International Atomic Energy Agency, Roberto F. Aguilera, Curtin University, Cristina L. Archer, California State University and Stanford University, Ruggero Bertani, Enel Green Power S.p.A., S.C. Bhattacharya, International Energy Initiative, Maurice B. Dusseault, University of Waterloo, Luc Gagnon, HydroQuébec, Helmut Haberl, Klagenfurt University, Monique Hoogwijk, Ecofys, Arthur Johnson, Hydrate Energy International, Mathis L. Rogner, International Institute for Applied Systems Analysis, Horst Wagner, Montan University Leoben, Vladimir Yakushev, Gazprom, Doug J. Arent, National Renewable Energy Laboratory, Ian Bryden, University of Edinburgh, Fridolin Krausmann, Klagenfurt University, Peter Odell, Erasmus University Rotterdam, Christoph Schillings, German Aerospace Center, Ali Shafiei, University of Waterloo, Ji Zou, Renmin University
- Global Energy Assessment Writing Team
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- Book:
- Global Energy Assessment
- Published online:
- 05 September 2012
- Print publication:
- 27 August 2012, pp 425-512
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Summary
Executive Summary
An energy resource is the first step in the chain that supplies energy services (for a definition of energy services, see Chapter 1). Energy services are largely ignorant of the particular resource that supplies them; however, often the infrastructures, technologies, and fuels along the delivery chain are highly dependent on a particular type of resource. The availability and costs of bringing energy resources to the market place are key determinants to affordable and accessible energy services.
Energy resources pose no inherent limitation to meeting the rapidly growing global energy demand as long as adequate upstream investment is forthcoming – for exhaustible resources in exploration, production technology, and capacity (mining and field development) and, by analogy, for renewables in conversion technologies.
Hydrocarbons and Nuclear
Occurrences of hydrocarbons and fissile materials in the Earth's crust are plentiful – yet they are finite. The extent of the ultimately recoverable oil, natural gas, coal, or uranium is the subject of numerous reviews, yet still the range of values in the literature is large (Table 7.1). For example, the range for conventional oil is between 4900 exajoules (EJ) for reserves to 13,700 EJ (reserves plus resources) – a range that sustains continued debate and controversy. The large range is the result of varying boundaries of what is included in the analysis of a finite stock of an exhaustible resource, e.g., conventional oil only or conventional oil plus unconventional occurrences, such as oil shale, tar sands, and extra-heavy oils.
Chapter 11 - Renewable Energy
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- By Wim Turkenburg, Utrecht University, Doug J. Arent, National Renewable Energy laboratory, Ruggero Bertani, Enel Green Power S.p.A., Andre Faaij, Utrecht University, Maureen Hand, National Renewable Energy Laboratory, Wolfram Krewitt, German Air and Space Agency, Eric D. Larson, Princeton University and Climate Central, John Lund, Geo-Heat Center, Oregon Institute of Technology, Mark Mehos, National Renewable Energy Laboratory, Tim Merrigan, National Renewable Energy Laboratory, Catherine Mitchell, University of Exeter, José Roberto Moreira, Biomass Users Network, Wim Sinke, Energy Research Centre of the Netherlands, Virginia Sonntag-O'Brien, REN21, Bob Thresher, National Renewable Energy Laboratory, Wilfried van Sark, Utrecht University, Eric Usher, United Nations Environment Programme, Dan Bilello, National Renewable Energy Laboratory, Helena Chum, National Renewable Energy Laboratory, Diana Kraft, REN21, Philippe Lempp, German Development Ministry, Jeff Logan, National Renewable Energy Laboratory, Lau Saili, International Hydropower Association, Niels B. Schulz, International Institute for Applied systems Analysis, Austria and Imperial College, Aaron Smith, National Renewable Energy Laboratory, Richard Taylor, International Hydropower Association, Craig Turchi, National Renewable Energy Laboratory, Jürgen Schmid, Fraunhofer Institute for Wind Energy and Energy System Technology
- Global Energy Assessment Writing Team
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- Book:
- Global Energy Assessment
- Published online:
- 05 September 2012
- Print publication:
- 27 August 2012, pp 761-900
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Summary
Executive Summary
Renewable energy sources – including biomass, geothermal, ocean, solar, and wind energy, as well as hydropower – have a huge potential to provide energy services for the world. The renewable energy resource base is sufficient to meet several times the present world energy demand and potentially even 10 to 100 times this demand. This chapter includes an in-depth examination of technologies to convert these renewable energy sources to energy carriers that can be used to fulfill our energy needs, including their installed capacity, the amount of energy carriers they produced in 2009, the current state of market and technology development, their economic and financial feasibility in 2009 and in the near future, as well as major issues they may face relative to their sustainability or implementation.
Present uses of renewable energy
Since 1990 the energy provided from renewable sources worldwide has risen at an average rate of nearly 2% a year, but in recent years this rate has increased to about 5% annually (see Figure 11.1.) As a result, the global contribution of renewables has increased from about 74 EJ in 2005 to about 89 EJ in 2009 and represents now 17% of global primary energy supply (528 EJ, see Figure 11.2). Most of this renewable energy comes from the traditional use of biomass (about 39 EJ) and larger-scale hydropower (about 30 EJ), while other renewable technologies provided about 20 EJ.
Chapter 4 - Geothermal Energy
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- By Barry Goldstein, Gerardo Hiriart, Ruggero Bertani, Christopher Bromley, Luis Gutiérrez-Negrín, Ernst Huenges, Hirofumi Muraoka, Arni Ragnarsson, Jefferson Tester, Vladimir Zui, David Blackwell, Trevor Demayo, Garvin Heath, Arthur Lee, John W. Lund, Mike Mongillo, David Newell, Subir Sanyal, Kenneth H. Williamson, Doone Wyborne, Meseret Teklemariam Zemedkun, David Wratt
- Edited by Ottmar Edenhofer, Ramón Pichs-Madruga, Youba Sokona, Kristin Seyboth, Susanne Kadner, Timm Zwickel, Patrick Eickemeier, Gerrit Hansen, Steffen Schlömer, Christoph von Stechow, Patrick Matschoss
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- Book:
- Renewable Energy Sources and Climate Change Mitigation
- Published online:
- 05 December 2011
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- 21 November 2011, pp 401-436
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Summary
Executive Summary
Geothermal energy has the potential to provide long-term, secure base-load energy and greenhouse gas (GHG) emissions reductions. Accessible geothermal energy from the Earth's interior supplies heat for direct use and to generate electric energy. Climate change is not expected to have any major impacts on the effectiveness of geothermal energy utilization, but the widespread deployment of geothermal energy could play a meaningful role in mitigating climate change. In electricity applications, the commercialization and use of engineered (or enhanced) geothermal systems (EGS) may play a central role in establishing the size of the contribution of geothermal energy to long-term GHG emissions reductions.
The natural replenishment of heat from earth processes and modern reservoir management techniques enable the sustainable use of geothermal energy as a low-emission, renewable resource. With appropriate resource management, the tapped heat from an active reservoir is continuously restored by natural heat production, conduction and convection from surrounding hotter regions, and the extracted geothermal fluids are replenished by natural recharge and by injection of the depleted (cooled) fluids.
Global geothermal technical potential is comparable to global primary energy supply in 2008. For electricity generation, the technical potential of geothermal energy is estimated to be between 118 EJ/yr (to 3 km depth) and 1,109 EJ/yr (to 10 km depth). For direct thermal uses, the technical potential is estimated to range from 10 to 312 EJ/yr. The heat extracted to achieve these technical potentials can be fully or partially replenished over the long term by the continental terrestrial heat flow of 315 EJ/yr at an average flux of 65 mW/m2.