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This blog is expressly directed to readers who do not have strong training or backgrounds in science, with the intent of helping them grasp the underpinnings of this important issue. I'm going to present an ongoing series of posts that will develop various aspects of the science of global warming, its causes and possible methods for minimizing its advance and overcoming at least partially its detrimental effects.

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Friday, September 6, 2013

China Considers Programs to Limit Greenhouse Gas Emissions


Summary.  The world’s use of energy is expanding.  Much of this demand is concentrated in developing countries of the world, especially China.  Their energy needs are furnished primarily by fossil fuels, leading to high annual rates of emission of the greenhouse gas carbon dioxide, increasing in China historically by 6.4% per year.  Coal is its principal fuel.

Jiang Kejun, a scientist at China’s Energy Research Institute, is urging its national energy policymakers to limit CO2 emissions more aggressively by emphasizing expanded renewable energy sources and energy efficiency.  Mr. Jiang notes that “time for effective action is very limited.”

The drastic, yet feasible, measures promoted by Mr. Jiang are resisted by energy and industrial interests in China, since they adversely affect China’s economic growth rate and threaten the viability of existing energy investments.  In the meantime, China is starting a handful of pilot projects using a cap-and-trade emissions market to limit emissions.  Additionally a carbon tax and direct limits on emissions are also under consideration.

Since China is a major contributor to increased greenhouse gas emissions, it is important that it undertake all feasible policies to limit them.  Global warming from manmade greenhouse gases is indeed a worldwide problem, requiring a global approach to solve it.  The total accumulated level of atmospheric greenhouse gases must be stabilized by reducing annual emission rates toward zero.


Introduction.  The worldwide demand for energy has been increasing relentlessly throughout the period of industrialization.  Most of this energy is provided by burning fossil fuels (coal, oil and natural gas) which results in corresponding increases in the atmospheric content of carbon dioxide (CO2), a significant and prominent greenhouse gas (GHG).  Combustion of fossil fuels is projected to continue increasing by several percent annually over the coming decades in the absence of meaningful worldwide efforts to minimize GHG emissions.

The annual emissions rate among industrialized countries of the world has been increasing very slowly in the last 10 years or so, because of both intrinsic economic factors and as a result of various reduction policies put in place.  Almost all the increase in the worldwide GHG emissions rate originates from developing countries, especially China, India, Brazil and Russia.  This results from the compounded effects of large populations and high rates of economic expansion as these countries strive to attain middle class living conditions.

This post focuses on actual and proposed policy changes in China that are intended to slow its rate of emitting GHGs.  China has the highest population of any country in the world, and its people are rapidly becoming more prosperous, placing great pressure on its economy to provide them a middle class life style.  These factors are shared across all the rapidly growing developing countries such as those listed above.

China’s economy has been expanding rapidly in recent years.  For the decade 1999-2009 the annualized growth rate of China’s economy (measured as real gross domestic product) was 10.3%.  This has slowed in the most recent years; China expects its growth rate to be 7.5% in 2013.  Such strong growth is necessarily fueled by corresponding growth rates in its use of energy, most of which comes from burning fossil fuels.  For example, the graphic below shows that most of China’s electricity has been generated from fossil fuels (turquoise shading).


Annual electrical energy generated for major input sources of energy.
Source: http://www.eia.gov/countries/cab.cfm?fips=CH

 
In 2011, according to the U. S. Energy Information Administration (EIA), 65% of electric generation and 70% of its total energy use was powered by coal, the fossil fuel that produces about twice as much CO2 per unit of electric energy obtained as natural gas, which supplied 3% of its energy.  Among renewable sources, 22% of electric power was obtained from hydropower (brown shading), 6% from wind power and only 0.2% from solar.

China’s domestic production of coal increased 9% from 2010 to 2011, becoming the world’s largest producer; including imports China alone consumes half the world’s coal output.  According to the Huffington Post, China brings a new coal-fired power plant on line every 7-10 days.  In addition to electricity generation, coal powers much of China’s industrial production.

By 2020, China seeks to provide 15% of its energy from renewable sources.  Hydropower will supply most of this, with wind power being next. 

China is expected to dramatically increase its overall energy consumption over 2010-2040, continuing its rapid growth in use of energy in recent years (see the graphic below).
 
 

Annual rates of energy usage for China, the U. S. and India.  Actual use up to 2010; projected usage thereafter.  1 quadrillion = 1 million billion.
Source: http://www.eia.gov/pressroom/presentations/sieminski_07252013.pdf (slide 5).

 
As China has drastically expanded its energy consumption in recent years, so too has its annual rate of CO2 emissions correspondingly.  In 2010 it emitted 7,885 million metric tons of CO2 (1 metric ton = ~1.1 U. S. (short) ton).  This represents the culmination of an average increase in annual emissions rate of 6.4%.  Projecting forward to the period 2010-2040 the EIA believes the emissions growth rate will fall to 2.1% per year.

It is clear from this background that any international effort to limit global warming by reducing GHG emissions must include China, as well as other developing countries whose emissions rates are increasing. 

Recent Efforts by China to Lower Its GHG Emissions Rate.  The rapid expansion of fossil fuel-driven electricity generation, automobile use and heavy industry in China has led in recent years to severe air pollution in Beijing and other large urban centers.  The New York Times reported on Aug. 31, 2013 that one environmental scientist, Jiang Kejun, working at the Energy Research Institute, is urging the national energy policymakers to limit CO2 emissions more aggressively than at present.  He is taking advantage of the growing tide of public concern over urban air pollution, which is causing China’s leaders to support “firmer, faster measures for cleaner air” that likely include reducing emissions.   With this change in public opinion behind him, Mr. Jiang and his colleagues advocate a program by which China’s annual emissions rate should reach a maximum by about 2025, and according to which that maximum would be lower than previously predicted.  It advocates more intensive emphasis on developing renewable energy sources, implementing energy efficiency technologies, optimizing China’s economic structure, technology innovation, low-carbon investments, and development and deployment of carbon capture and storage (CCS, see an earlier post and the Note at the end of this post).

Mr. Jiang, like most climate scientists, recognizes that “time for effective action is very limited.”  It still remains for Chinese policymakers to adopt such aggressive measures.  The Times report notes instead that other, less drastic, policies are being implemented or contemplated.  A pilot project is setting up a cap-and-trade emissions market in Shenzhen.  Six more pilots are planned to start by 2015.  The affected emissions are only a miniscule portion of China’s total amount.  Other proposals, not yet implemented, include a tax on carbon dioxide emissions and guiding limits on emission rates.

Growth vs. Emissions Limits.  China’s government has to balance its decades-old imperative of rapidly expanding its economy with the newer considerations of constraining emissions from fossil fuels.  Expansion has relied on conventional technologies that are fossil fuel-intensive; such facilities have useful service lifetimes of several decades and continue to emit GHGs throughout this period.  Policies constraining GHG emissions threaten the investments made in these facilities, since they may have to be extensively retrofitted or removed from service to accommodate emissions limitations.  Even so, over the past decade or so the government has successfully adopted a policy of increasing China’s economic emissions efficiency, the weight of CO2 released in producing a unit national gross domestic product.  This measure has been reduced significantly over this period, by 2-4% per year.  Nevertheless, since fossil fuel energy demand grows annually by an even larger percentage (see above), China’s net CO2 emissions continue to increase in spite of gains in efficiency.

Analysis

Global warming refers to the increase in the long-term (annual to decadic) worldwide average temperature above the temperature before the industrial revolution.  It is directly related to total accumulated level of CO2 and other GHGs in the atmosphere, not to the annual rate of worldwide GHG emissions.  CO2 in particular, once emitted, persists in the atmosphere for a century or even longer.  There is no natural mechanism that depletes atmospheric CO2 in this short a time frame.  Therefore even if the countries of the world agree to lower emission rates, GHGs continue to accumulate, until the effective rate approaches zero.  The long-term average worldwide temperature will continue increasing throughout this period, and will stabilize at a new, higher temperature when emissions rates fall toward zero.

Global warming is just that, a worldwide phenomenon that merits international attention.  Countries whose emission rates continue increasing (see the graphic above) are of special concern; this includes large sources in developing countries such as China and others.

The worsening crisis of urban air pollution in China’s major cities appears to be the trigger leading China’s leaders to contemplate putting emissions limits in place.  The corresponding crisis of global warming itself apparently has been insufficient so far to lead to a similar intensification of effort, in spite of harmful extreme weather events occurring in China and elsewhere in Asia.  Such events are at least made worse by, if not wholly due to, the adverse effects of global warming.  Mr. Jiang’s programs, if approved for action, should make a major contribution to reducing China’s GHG emission rate. 

As we grapple with the need to limit GHG emissions in order to stabilize global warming we should understand that abating emissions may be considered a zero-sum enterprise.  When contemplating investing in new energy facilities either we  can continue building conventional facilities (fossil fuel generating plants; fossil fuel-powered cars) with need to expand fuel pipelines and transporting fuels, or we can build renewable energy facilities coupled with new electric transmission lines (providing the energy for electric-powered modes of transportation).  Choosing renewable energy contributes to lowering emissions rates, preserves economic activity and maintains the demand for labor. 

It is strongly recommended to develop renewable energy whenever the choice confronts us.

Note

Carbon capture and storage is an experimental technology, currently operational yet open to improvement, that captures CO2 from fixed power facilities, compresses it and forces it into underground reservoirs intended to retain it for thousands of years.  As such it is particularly suited for deployment in China, since coal fuels so much of its electricity generation.  Unfortunately, currently there are only four pilot scale CCS projects in China, far fewer than elsewhere in the world.  Not all of them are directly related to capturing and storing CO2 emissions from power generation.  If CCS technology becomes operational, each power plant would incorporate it and deliver the resulting CO2 into stable geological storage sites.

© 2013 Henry Auer


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