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Thursday 31 January 2013

Summary.  Coal is the worst of the three principal fossil fuels in terms of the amount of carbon dioxide, the main greenhouse gas, emitted into the atmosphere on burning.  Whereas annual rates of emission from developed countries are projected to remain steady, the emission rates from developing countries are predicted to rise by almost 3% per year as they burn more and more fossil fuels, mostly coal, each year.



Consequently, according to a growing group of leading climate scientists, the goal of limiting the long-term global average temperature rise to less than 2.0ºC (3.6ºF) likely will not be met.  This will have serious negative consequences on humanity and the planet. 

We conclude that every new investment in energy infrastructure starting “now” should construct renewable energy sources and institute energy efficiency instead of extending fossil fuel-based energy infrastructure.  The principal emitters of greenhouse gases, including the U. S. and China, should reach a “few-party” agreement to decarbonize their energy economies among themselves as soon as possible.

 
Introduction.  Coal is the worst of the three principal fossil fuels in terms of how much carbon dioxide (CO2), the main greenhouse gas, is emitted into the atmosphere for a given amount of heat produced on burning.  This is shown in the following table. 


It is seen that, on the basis of carbon-atom-to-carbon-atom in the various fuels,  coal emits almost twice as much CO2per unit of heat obtained relative to natural gas.  This makes coal the most offending of the fossil fuels in contributing to the worsening of global warming. 

In view of this situation, it would be highly sensible to set policies in place that discourage expansion of coal-burning energy sources.  Yet coal is also highly abundant throughout the world, and readily mined at the scale needed to satisfy energy demand.  Indeed, use of coal for energy continues not merely at a level pace, but at an ever-growing rate, as energy demand around the world keeps increasing.

Growth in energy use and in emissions of greenhouse gases in China and other developing countries has been historically high, and is expected to continue growing in future decades (see Details at the end of this post).  China is the country with the greatest demand for energy sources, coupled with a very high rate of growth in its energy demand.  A large portion of its energy demand is provided by coal.  Use of coal for energy in China grew at an average rate of 8.8% per year from 2000 to 2011, while the rate for the rest of the world was 1.1% per year.  Overall, China’s total energy use more than doubled over this time period, closely tracking the growth in its economy.  Clearly, energy is needed to power expansion in production and infrastructure.

The U. S. Energy Information Administration (USEIA) foresees continued rapid growth in energy consumption in China, as well as in India, in the future decades from 2008 through 2035.  Most of this energy continues to be derived from coal and other fossil fuels, so their projected emissions of the greenhouse gas carbon dioxide likewise grow rapidly during this period. 

Energy use by India, though lower in absolute magnitude than that of China, also grows at a comparable rate, since its energy economy is also being developed with a strong reliance on coal.  In contrast, the growth in energy use among developed countries, and their corresponding annual rate of growth of greenhouse gas emissions, is much lower than that for China, India and other developing countries of the world.

Analysis

China, India and other developing countries of the world have relied on coal and other fossil fuels to provide the energy needed to power their economic growth (as have most developed countries as well).  Coal is the most offensive of these fuels, for on burning it releases almost 50% to about 90% more carbon dioxide, the major greenhouse gas, than other fuels.  This unremitting reliance on fossil fuels has resulted in a dramatic growth in the emissions of CO2, and is expected to continue without significant change in future decades (see Details, below), in the absence of new energy policies curtailing greenhouse gas emissions.

CO2released into the atmosphere is rapidly distributed into the air all around the globe; it does not remain restricted to the air space over the region of the emitting source.  For this reason greenhouse gas emissions at any point on the planet exert their greenhouse effect on all humanity.  Every source of greenhouse gas emissions contributes to the climatic consequences of global warming inflicted across the face of the entire planet.  The developing countries of the world, for example, are continuing to expand their energy infrastructures by installing still more electric generating plants, industrial facilities, and motor vehicle fleets, mostly powered by fossil fuels, as seen in the projections for future fuel use and CO2 presented in this post.  We must understand, however, that every new facility made operational today cements a commitment to continue emitting CO2throughout its operational lifetime: up to a century for housing and commercial structures, about 40-50 years for electric power plants, and 10-20 years for motor vehicles.  The actions our policymakers take today have decades-long consequences.

CO2, once emitted into the atmosphere, remains airborne indefinitely for at least 100 years, if not much longer (after a fixed, known fraction, about one-third, is absorbed by oceans).  Humanity has been adding new CO2 to the atmosphere since the industrial revolution began, and is doing so as shown in the Details at an ever-increasing rate.  The extent of increase of the global average temperature is determined by the total accumulated level of GHGs, not by the annual rate of emissions. The present level has already raised the long-term global average temperature by 0.7ºC (1.3ºF).  This increase is continuing higher as the CO2concentration continues to increase. 
The Intergovernmental Panel on Climate Change (IPCC)  has set a target of limiting emissions such that the overall global average would not increase more than 2.0ºC (3.6ºF).  But climate scientists, examining current trends in the use of fossil fuels, now realize that humanity will fail to meet this target (these include Sir Robert Watson, former Chair of the IPCC; James Hansen, climate scientist at the National Aeronautics and Space Administration’s Goddard Institute for Space Studies ; Glen Peters and coworkers, Nature Climate Change vol. 3, pp. 4–6 (2013), doi:10.1038/nclimate1783;and Greenpeace “Point of No Return, The massive climate threats we must avoid”, January 2013).  

Recent annual conferences held by the United Nations Framework Convention on Climate Change (UNFCCC), including those in Copenhagen (2009), Cancun (2010) and Durban (2011), have striven unsuccessfully to supplant the Kyoto Protocol on its expiration at the end of 2012.  At the Durban conference it became clear that agreement on a global warming treaty would be seriously delayed.   As confirmed at the Dubai conference in 2012, the objective now is to conclude negotiating a new treaty by 2015 for adoption by the nations of the world and implementation by 2020.

But this is most likely too late.  As seen in the projections shown in this post, representing trends in the absence of policies to reduce emissions, annual emission rates by developed countries will continue at a constant level, while annual rates by developing countries will rise indefinitely.  Neither of these trends points to reduced emissions.  Yet this is what is needed.  Moderate abatement measures instituted a decade or two ago would have been relatively easy to implement.  But in the meantime, in their absence, global emissions have raised the CO2 content of the atmosphere, so now more drastic abatement measures have to be implemented as soon as possible. 

Thomas F. Stocker, a climate scientist at the University of Bern, Switzerland, calculates (Science2013: Vol. 339 pp. 280-282; doi: 10.1126/science.1232468)  that the longer the delay the more stringent the mitigation policy must be to attain a goal of any given maximum temperature increase over the preindustrial temperature.  As of now, for example, an ambitious goal of a limiting rise of 1.5ºC (2.7ºF) would need a relatively stringent abatement rate of more than 5% per year, while a higher limit of 2.0ºC (3.6ºF) would need a lower abatement rate of over 2% per year.  But if we wait until 2020, for example, a limiting rise of 1.5ºC would require almost a 10% per year abatement rate, and a limiting rise of 2.0ºC would require about a 3% abatement rate.  Dr. Stocker concludes “…even well-intentioned and effective international efforts to limit climate change must face the hard physical reality of certain temperature targets that can no longer be achieved if too much carbon has already been emitted to the atmosphere. Both delay and insufficient mitigation efforts close the door on limiting global mean warming permanently” (emphasis added).

This post concludes that every investment in energy infrastructure undertaken from this date forward should construct decarbonizing energy facilities and implement energy efficiency instead of extending fossil fuel-based energy infrastructure.  These measures can be initiated unilaterally, but in addition the principal emitters of greenhouse gases, including the U. S. and China, should reach a “few-party” agreement to decarbonize their energy economies among themselves as soon as possible, outside of the UNFCCC process.  Our climate future and that of coming generations demands nothing less.

 Details

The historical use of coal by China, and by all other countries, is shown in the following graphic.
Coal consumption, in billions of tons used per year, from 2000 to 2011 for China (red line) and the rest of the world (black line).
Source: U. S. Energy Information Administration, http://www.eia.gov/todayinenergy/detail.cfm?id=9751&src=email.
 

In all countries of the world not including China (black line), coal use grew from 3.8 billion tons per year to 4.3 billion tons over the eleven years shown.  This works out to an average growth rate of 1.1% per year.  In contrast, coal use in China grew from 1.5 billion tons per year in 2000 to 3.8 billion tons in 2011, for an average growth rate of 8.8% per year.  Use in 2011 grew by 9%, continuing the long-term trend. 

World trends for coal use for 1980 and 2010 are shown in the two images below

 


World use of coal in 1980 and 2010 in billions of tons (Images captured from an animated version tracing year by year changes).   While North American use has expanded slightly, coal use in Europe and the former Soviet Union has actually fallen.  In the same period, coal use in Asia, due primarily to China and India, has expanded dramatically.
Source: U. S. Energy Information Administration http://www.eia.gov/todayinenergy/detail.cfm?id=4390.
 

This link animates the above images year by year between the 1980 and 2010 endpoints.  The two still images and the animation bring home in striking visual impressions the vast growth in Asian coal use, originating mostly in China and India.

The growth in overall energy use by China tracks quite exactly with its economic expansion, as seen below:
 
 
Total energy use by China (in quadrillion British thermal units (aqua bars)) and its economic growth (in 2000 U. S. constant $ (brown line)).
Source: U. S. Energy Information Administration http://www.eia.gov/todayinenergy/detail.cfm?id=8070.
 
About 71% of China’s electricity originates from thermal generation, mostly powered by coal.  Electricity generation doubled between 2005 and 2011, with coal-fired generation growing proportionately.  In some years in this period, China was commissioning 1-2 new coal-fired electricity plants per week. Even though China has the largest coal reserves in the world, it imports additional coal to meet its demand, starting in 2009.  (A detailed accounting of China’s historical energy economy is available at the USEIA).
 
In 2010, China accounted for about 73% of Asia’s coal use.  From 1980 to 2010 Asia’s coal use increased 403% during a period in which total world use increased 94% and North America’s use increased 50%.  In 1980 Asia accounted for 24% of the world’s total use of coal, while in 2010 this share grew to 63%. (Source: U. S. Energy Information Administration).
 
 
USEIA published its International Energy Outlook 2011 in September 2011.  Using a Reference scenario which assumes no further governmental energy policies other than those already in place in 2011 it projects trends in energy production and consumption from 2008, the last year of historical data included, through 2035.  As seen in the graphic below, total energy use in China and in India increases by much higher annual growth rates than does the increase in usage by the U. S.
 
Source: U. S. Energy Information Administration http://www.eia.gov/forecasts/ieo/world.cfm
 
China and India, continuing the historical trend already noted, derive much of their energy in the period projected through 2035 by burning coal.  This contributes to large accumulations of atmospheric CO2.  This is seen in the following graphic:

Historical emissions of CO2 from 1990 to 2008, and projections under the Reference Scenario to 2035 for developed countries (OECD, black line) and developing countries (non-OECD, red line). Source: U. S. Energy Information Administration; http://www.eia.gov/forecasts/ieo/emissions.cfm.
 
Emissions for developed countries in the Organization for Economic Development (OECD) increase minimally over the projected period, while those for the non-OECD countries increase 73% from 2008 to 2035, to 28.9 billion metric tons of CO2.  Emissions originate worldwide mostly from coal, then from liquid fuels (powering transportation), then natural gas.  The growth in emissions from coal originates almost entirely from developing countries, which are dominated by emissions from China and India.  Growth rates for emissions from China and India are 2.6% per year and 2.7% per year, respectively, and the rate for all developing countries is 2.1% per year.  By contrast, the growth rate for emissions from developed countries is only 0.2% per year.

 © 2013 Henry Auer

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