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Production Overview

Major Sources

Most of the world's energy comes from fossil fuels--coal, oil, and natural gas--and most non-fossil energy comes from nuclear power and hydroelectricity, with a growing share from renewable energy. The world energy mix has remained relatively stable.

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Source: BP 1.

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Sources of world primary energy. "Renewable" sources include wind, solar, geothermal, biofuels, wave, and tidal, but not hydropower. Source: BP 1. Note that BP's figures differ slightly from the primary energy statistics reported by the Energy Institute 2.

Economics

Following are estimates of the cost of producing electricity from major sources.

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For source information, see our analyses on coal, natural gas, oil, hydropower, nuclear, solar, wind, geothermal, and ocean energy.

Distributed energy sources are necessary for locations not served by centralized grids, such as remote communities and military installations, but tends to be more expensive.

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A sampling of estimates of levelized costs of distributed energy sources. Costs are highly variable and depend on local conditions. Sources are as follows for diesel generators 3, solar 4, 5, 6, 7, wind 6, biomass 6, micro-hydro 7, nuclear micro-reactors 8, and fuel cells 9.

Usage of Fossil Fuels

The three classes of fossil fuels are used in different ways.

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Use of coal, oil, and natural gas in major sectors of the economy. Consumption figures for transportation and agriculture, industry, and buildings exclude electricity. Source: IEA 10.

Any successful effort to decarbonize the economy must address industry, particularly the heavy direct fossil fuel usage in industrial processes. In addressing oil dependence, alternatives for liquid fuels in transportation are essential.

Production Potential

The world should have sufficient nonrenewable energy resources for the foreseeable future.

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Proven, economical reserves of major energy sources. As exploration continues and extraction technology improves, reserves should continue to expand. Source: World Energy Council 11.

The resources of geothermal, nuclear fission, and fusion energy are far vaster.

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World primary energy production is about 600 exajoules, or 0.6 zetajoules, per year. Sources: 12.

Among renewable energy sources, solar and possibly offshore wind should be available and economically feasible in sufficient quantities to meet world energy needs.

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World production potential from various renewable energy sources. Most estimates are given by the World Energy Council 11, with additional estimates on wind and solar potential from Deng et al. 13, wave from Gunn and Stock-Williams 14, Ocean Thermal from the National Research Council 15, osmotic power from Stenzel and Wagner 16, and biomethane from the IEA 17. Figures are all conservative estimates of the limits of economically practical production with near-term technology; technical production potential, or the potential with more advanced technology, may be much greater. The practical short term limits on nuclear and fossil fuel production are unclear, though long term limits may be imposed by the resource base, as shown above.

Energy Return on Energy Invested

The energy return on energy invested (EROEI), based on the return on investment concept in finance, is the ratio of the energy producted by a given technology to the energy consumed by the production system. Low EROEI values may indicate that a technology is inherently unviable.

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Estimates of EROEI for different energy sources. Values should be regarded as highly uncertain. Sources: Arodudu et al. 18 on biomass and biofuels, Bhandari et al. 19 on solar, Kampa 20 on geothermal, most energy sources from Hall et al. 21, and additional estimates for most electricity sources from Weißbach et al. 22. Values are reported as ranges, as for most energy sources there are multiple estimates available.

For Further Reading

Vaclav Smil's long term perspective on energy in the human economy.

References

  1. BP. "Statistical Review of World Energy 2022". 2022. ↩ ↩2

  2. Energy Institute. "Statistical review of World Energy". Accessed July 30, 2023. ↩

  3. Oviroh, P., Jen, T. "The Energy Cost Analysis of Hybrid Systems and Diesel Generators in Powering Selected Base Transceiver Station Locations in Nigeria". Energies 11(3), 687. March 2018. ↩

  4. Kost, C., Shammugam, S., Jülch, V., Nguyen, H., Schlegl, T. "Levelized Cost of Electricity: Renewable Energy Technologies". Fraunhofer Institute for Solar Energy Systems ISE. March 2018. ↩

  5. Lazard. "Lazard's Levelized Cost of Energy Analysis - Version 12.0". November 2018. ↩

  6. Mayor, B., Rodríguez-Muñoz, I., Villarroya, F., Montero, E., López-Gunn, E. "The Role of Large and Small Scale Hydropower for Energy and Water Security in the Spanish Duero Basin". Sustainability 9(10), 1807. October 2017. ↩ ↩2 ↩3

  7. Taufiqurrohman, I. "The Assessment of Off-Grid Photovoltaic (PV) Systems for Rural Electrification in Indonesia". 3rd International Conference of Integrated Intellectual Community (ICONIC) 2018. July 2018. ↩ ↩2

  8. Nichol, M., Desai, H. "Cost Competitiveness of Micro-Reactors for Remote Markets". Nuclear Energy Institute. April 2019. ↩

  9. International Energy Agency, Nuclear Energy Agency, Organization for Economic Co-Operation and Development. "Projected Costs of Generating Electricity: 2015 Edition". September 2015. ↩

  10. International Energy Agency. "Sankey Diagram". Accessed April 18, 2019. ↩

  11. World Energy Council. "World Energy Resources". 2016. ↩ ↩2

  12. Hermann, W., Simon, A. J. "Global Exergy Flux, Reservoirs, and Destruction". Global Climate and Energy Project at Stanford University. 2005, 2007. ↩

  13. Deng, Y. et al. "Quantifying a realistic, worldwide wind and solar electricity supply". Global Environmental Change 31, pp. 239-252. March 2015. ↩

  14. Gunn, K., Stock-Williams, C. "Quantifying the global wave power resource". Renewable Energy 44, pp. 296-304. August 2012. ↩

  15. National Research Council. An Evaluation of the U.S. Department of Energy's Marine and Hydrokinetic Resource Assessments. Washington, DC: The National Academies Press. Chapter 5: Ocean Thermal Energy Conversion Resource Assessment. 2013. ↩

  16. Stenzel, P., Wagner, H. "Osmotic power plants: Potential analysis and site criteria". 3rd International Conference on Ocean Energy. October 2010. ↩

  17. International Energy Agency. "Outlook for biogas and biomethane: Prospects for organic growth". March 2020. ↩

  18. Arodudu, O., Voinov, A., van Duren, I. "Assessing bioenergy potential in rural areas - A NEG-EROEI approach". Biomass and Bioenergy 58, pp. 350-364. November 2013. ↩

  19. Bhandari, K., Collier, J., Ellingson, R., Apul, D. "Energy payback time (EPBT) and energy return on energy invested (EROI) of solar photovoltaic systems: A systematic review and meta-analysis". Renewable and Sustainable Energy Reviews 47, pp. 133-141. July 2015. ↩

  20. Kampa, K. "An energy return on investment for a geothermal power plant on the Texas Gulf Coast". University of Texas Electronic Theses and Dissertations. May 2013. ↩

  21. Hall, C., Lambert, J., Balogh, S. "EROI of different fuels and the implications for society". Energy Policy 64, pp. 141-152. January 2014. ↩

  22. Weißbach, D., Ruprecht, G., Huke, A., Czerski, K., Gottlieb, S., Hussein, A. "Energy intensities, EROIs (energy returned on invested), and energy payback times of electricity generating power plants". Energy 52, pp. 210-221. 2013. ↩