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Toward Decoupling: Growing GDP without Growing Carbon Emissions Qiang Wang,*,† Rongrong Li,† and Hua Liao‡,§ †
School of Economics and Management, China University of Petroleum (huadong), No. 66, Changjiang West Road, Huangdao District, Qingdao, 266580, China ‡ Center for Energy and Environmental Policy Research, Beijing Institute of Technology, Beijing 100081, China § School of Management and Economics, Beijing Institute of Technology, Beijing 100081, China and energy consumption from BP are used. The change in energy-related CO2 emission (F) can be deconstructed into change in (1) population (P); (2) per-capita GDP (g); (3) energy intensity of GDP (e); and (4) carbon intensity of energy ( f), that is, F = P × g × e × f. The increased rates in population (P) and mean income (g) for 2015 were slightly slower than their 1980−2015 average. The long-term decline in energy intensity of GDP (e) has been accelerated, with an average growth rate from −0.89% yr−1 for 1980−2015 to −1.45% yr−1 in 2015. The long-term trend of carbon intensity of energy ( f) has also accelerated, with an average growth rate of −0.27% yr−1 for 1980−2015 but −0.86% yr−1 in 2015. Thus, the GDP-GHG decoupling in 2015 is a result of a relatively small growth in mean income (g) and in population (P), offset by a sharp decrease in the carbon intensity of energy (f) and energy intensity of GDP (e). To be more precise, together with the long-term improvement in energy efficiency, the recent sharp decrease in carbon intensity of energy was a significant factor in the decoupling of GDPGHG in 2015. If the carbon intensity of energy in 2015 had fallen at the long-term average of −0.27% yr−1, rather than of −0.86%, and the energy intensity of GDP had fallen at the long-term average of −0.89% yr−1 for 1980−2015, rather than The COP21 agreement in Paris, the landmark international by −1.45%, then the growth in global emissions in 2015 would climate change accord reached in December 2015, commits all have been 1.28% instead of 0.11%. countries, rather than just the wealthy ones, to tackling global Is decoupling an emerging trend or an anomalous blip? The warming. However, without breakthroughs in a decoupling of answer is currently unclear. However, as shown in Figure 1, the economic growth and greenhouse gas (GHG) emissions, long-term trend of carbon intensity of energy ( f) and energy governments are likely to remain reluctant to take aggressive intensity of GDP (e) suggests that global decoupling of GDPactions to cut GHG emission because those actions involve the GHG in 2015 might be more of an indication of an emerging risk of economic losses. In this paper, we compile data from the trend than an anomalous blip. BP energy review and the World Bank to show that in 2015 the Given that China has set a target of obtaining 15% of its world experienced economic growth without growth in carbon energy from renewables by 2020, and 20% by 2030, and India emission. has committed to cutting the carbon intensity of GDP by 33− Global energy-related carbon dioxide (CO2) emissions−the 35% by 2030 from 2005 level,4 the carbon intensity of energy in largest source of anthropogenic GHG emissions−increased by 1 non-OECD countries will further decrease. With EU countries 0.11% in 2015, according to recent BP energy review. well on the way to meeting their target of 20% renewable Meanwhile, global GDP (gross domestic product) grew by energy in energy supply by 2020, and U.S. shale gas continuing 2.47% in 2015, according to recent World Bank data.2 There is to replace coal, the movement away from energy systems no historical precedent for carbon emissions to remain at prior dependence on coal and oil, and toward natural gas and levels during a period of economic expansion. The other four renewables usage, is seemed to be irreversible in OECD periods in which energy-related CO2 emissions remained flat or countries. fell compared to the previous year, the early 1970s, early 1980s, China has set a target of cutting energy intensity by 40−45% 1992, and 2009, were associated with global economic 3 by 2020 from 2005 levels,4 and India has determined that recession or weakness. To understand the factors influencing the GDP-GHG decoupling in 2015, kaya identity and time-series data on Received: October 11, 2016 population and GDP from the World Bank, carbon emission © XXXX American Chemical Society
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DOI: 10.1021/acs.est.6b05150 Environ. Sci. Technol. XXXX, XXX, XXX−XXX
Viewpoint
Environmental Science & Technology
Figure 1. Trajectory of energy consumption per unit of GDP (e) and carbon emission per unit of energy consumption (f) in OECD and non-OECD between 2000 and 2015. Notes: Energy is total primary energy consumption measured in tonnes of oil equivalent. Carbon dioxide emissions are those from fuel combustion, measured in tonnes of carbon dioxide.1; GDP is market price at constant 2010 U.S. dollar, population data.2
countries to decouple; and (3) what lessons can be learned from those countries that successfully achieve GDP-GHG decoupling.
improvement in energy efficiency is a priority measure in tackling climate change. The two key countries’ policies indicate that energy intensity in non-OECD countries will continue its decline. EU countries are well on the wary to meet the 20% energy efficiency target by 2020 and the U.S. is committed to setting stricter mandatory energy efficient targets, such as one of 54.5 miles per gallon (mpg) for cars and lightduty trucks by 2025. Hence, the long-term trend of energy intensity is one of decline. The global GDP-GHG decoupling in 2015 could have profound implications for the future of climate policy. The phenomenon demonstrates that economic growth without growth in carbon emission is not a hypothesis, but a practical reality and that restricting global warming to 2 °C above preindustrial levels will not necessarily stunt growth. What is urgently needed now is for governments to take decisive actions to improve energy efficiency and shift to a less carbonintensive energy system. The priority for improving energy efficiency in developed countries should be centered on areas of consumption such building and vehicles. The priority in developing counties should be on production areas. A significant proportion of coal-fired power plants in developing countries are inefficient (30% or lower); an increase in energy efficiency of coal power plants from the current 30% to the state-of-the-art 50% could potentially reduce CO2 emissions by almost one-third.5 In addition, implementing a carbon tax on coal, petroleum, and natural gas based on the tons of CO2 produced per unit of fuel could effectively promote the use of renewable energy. Since the industrial revolution, researchers have got used to watching the global economy burn coal, oil, and gas to run various economic activities. They assumed−as an article of faith−that economic growth could not occur without increased energy consumption and concomitant carbon emission. Compared to this, the decoupling of GDP-GHG at the global-level is just the beginning. Therefore, more effort is required in the field of research including, but are not limited to, work on (1) the status and outlook for GDP-GHG decoupling at the national-level; (2) the driving forces for these
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AUTHOR INFORMATION
Corresponding Author
*E-mail:
[email protected]. Notes
The authors declare no competing financial interest.
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ACKNOWLEDGMENTS This work is supported by the Initial Founding of Scientific Research for the Introduction of Talents of China University of Petroleum (Huadong) (05Y16060020).
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REFERENCES
(1) BP, BP Statistical Review of World Energy 2016; British Petroleum: London, 2016; http://www.bp.com/en/global/corporate/energyeconomics/statistical-review-of-world-energy.html. (2) World Bank Open Data. http://data.worldbank.org/ (accessed September 29, 2016). (3) Peters, G. P.; Marland, G.; Le Quere, C.; Boden, T.; Canadell, J. G.; Raupach, M. R. Rapid growth in CO2 emissions after the 2008− 2009 global financial crisis. Nat. Clim. Change 2012, 2 (1), 2−4. (4) Wang, Q.; Li, R. Journey to burning half of global coal: Trajectory and drivers of China’s coal use. Renewable Sustainable Energy Rev. 2016, 58, 341−346. (5) IEA. Energy Technology Perspectives 2012: Pathways to a Clean Energy System; International Energy Agency: Paris, 2012; http://www. iea.org/etp/publications/etp2012/.
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DOI: 10.1021/acs.est.6b05150 Environ. Sci. Technol. XXXX, XXX, XXX−XXX
