See the Tabbed Pages for links to video tutorials, and a linked list of post titles grouped by topic.

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.

Each post will begin with a capsule summary. It will then proceed with captioned sections to amplify and justify the statements and conclusions of the summary. I'll present images and tables where helpful to develop a point, since "a picture is worth a thousand words".

Showing posts with label hydroelectric. Show all posts
Showing posts with label hydroelectric. Show all posts

Friday, November 14, 2014

The U. S. and China Announce Joint Emissions Reductions

People in China and the U. S. feel the effects of global warming in their daily lives.  Smog in Beijing and other cities, driven in part by burning coal for electric generation, severely impacts the lives of Chinese citizens.  During the Asia-Pacific Economic Cooperation (APEC) summit Nov. 11-14, 2014, China closed factories and gave workers time off in Beijing to reduce emissions while foreign officials were there.   While the average global temperature has risen worldwide since the industrial revolution began, the average temperature in China has risen even more.  The frequency of extreme weather and exceptional natural disasters such as droughts, dust storms, heavy rains, flooding and mudslides in China has risen in recent decades.  Urbanization has increased in China’s coastal cities, such as Shanghai, Tianjin and Hong Kong, making them more vulnerable to inundations from rising sea levels.

American coastal cities such as Miami Beach and Norfolk, Virginia routinely suffer high tide flooding.  According to the U. S. National Climate Assessment (May 2014),
warming has already had adverse effects across the U. S., including heat waves, droughts, wildfires, changes in availability of water, floods, ocean storm surges, extreme weather and climate events and socioeconomic effects.  Worsening of these trends is foreseen during this century.

Global warming from man-made greenhouse gases (GHGs), such as carbon dioxide (CO2), is clearly a problem confronting all humanity, requiring the cooperation of all nations of the world to address it.  Once emitted into the atmosphere, GHGs disperse across the entire globe.  Multinational efforts to conclude a new global warming treaty are currently under way.  Nevertheless, some experts have suggested that agreements between two or a small set of nations could play an important role as well.  Along these lines the U. S. and China announced a joint agreement to address GHG emissions on Nov. 12, 2014, during the APEC summit.

President Obama and President Xi pledged that their countries would significantly reduce emissions of GHGs over the next 15 years, each in their own way.  They agreed that

  • the U. S. would lower its GHG emission rates by 26-28% from the levels emitted in 2005, by 2025.  (The U. S. has already pledged to reduce emissions by 17% from the levels of 2005 by 2020.)  This requires an increasing the intended annual rate of reduction of GHG emissions from 1.2% per year up to 2020 to 2.3-2.8% per year between 2020 and 2025.
 
  • China’s emission rates, which continue growing because it is adding new fossil fuel-driven electric generating plants to power its expanding economy, will reach a maximum annual rate by 2030 and possibly sooner.  China’s commitment to slow the growth of its emissions was not specified in numerical terms.  As part of this initiative China expects to increase the share of energy derived from renewable sources (solar power, wind, nuclear and hydroelectric) to 20% by the target date of 2030.
 
  • The two nations agreed to extend and expand their cooperation in reducing emissions of hydrofluorocarbons, used in refrigeration, originally announced in 2013.  These substances are far more potent GHGs than CO2.

These commitments are being made by the two countries that are the two highest-emitting nations of the world, accounting for over one-third of annual global emission rates of GHGs.  The importance of these pledges cannot be exaggerated.

  • The commitments pledge major reductions in GHG emission rates by each of the two nations.
 
  • The agreement was reached outside the framework of the worldwide United Nations sponsored negotiations for a universal treaty.  Those negotiations, occurring annually for many years, have been fraught with contention and disagreements.
 
  • The commitments made by the two largest emitters of GHGs in the world to reduce emission rates should serve as a powerful incentive for other nations to reduce their emissions, whether individually or within the U. N. framework, to reach a meaningful agreement.

There is need for caution as well as enthusiasm in evaluating this agreement.  The U. S. White House put out a press release concerning this bilateral agreement on behalf of Presidents Obama and Xi.  This writer sought and could not find a corresponding English-language announcement on the web site of People’s Daily, the Chinese government’s newspaper, for Nov. 12, nor for Nov. 13, 2014.  However, China Daily, a non-governmental English language newspaper, did report the announcements.  If accurate, this leaves an impression that the Chinese government preferred to downplay or dissociate itself from the agreement even as President Obama embraced it.

This is not a binding agreement between parties.  As the White House wrote, the two parties separately announced goals or commitments to attain their respective targets by their respective dates.  President Obama has only two years left in office, so that most of the target conditions will have to be fulfilled by his successor(s).  A future president could just as well decide against following through on the present commitments.  He also faces a hostile Congress which may interfere with his intentions. 

President Xi heads a central government, so it may be easier for him to follow through on his commitments (see below, discussion on Five Year Plans).

The agreement imposes very different constraints on the two governments.  The American commitment is for numerically stated, and verifiable, reductions in emission rates.  The Chinese commitment, however, fails to specify a numerical standard for the extent of its reduction in emission rates.  The announcement states only that China will reduce the growth rate of its annual emissions until a maximum rate is achieved by 2030, or perhaps earlier.  Presumably China’s emission rate will actually begin falling after 2030, but this also is not stated.  (A common objective among climate scientists and policymakers, in order to keep the world’s global average temperature rise below 2ºC (3.6ºF), is that global emission rates have to be cut by 80% or more by 2050 below early 21st century levels.)

China’s Five Year Plans (FYPs) have already programmed in significant changes.  China’s national development is set forth in successive FYPs, which are assembled by China’s central government.  According to the report “Delivering Low Carbon Growth – A Guide to the 12th Five Year Plan”,  the proportion of energy provided by non-fossil fuel sources is to be 11.4% in the 12th FYP (2011-2015) and 15.0% in the 13th FYP (2016-2020).  So it is seen that much of the goal in November’s bilateral agreement is already planned, leaving an additional 5% of total energy to be provided by non-fossil fuel sources in the ten years leading to 2030 in order to reach the specified 20% objective.

China Daily reported that the bilateral agreement used earlier language that has always distinguished between developing and developed countries.  The wording was first presented in the U. N. Framework Convention on Climate Change twenty years ago, namely, that nations of the world address climate change “on the basis of equity and in accordance with their common but differentiated responsibilities and respective capabilities”.   This phrasing reflects the concerns that “the developed countr[ies] should take the lead in combating climate change” and that the “specific needs and special circumstances of developing countr[ies]…should be given full consideration”.  

China Daily reported that in the bilateral agreement "the two countries are committed to reaching an ambitious 2015 agreement that reflects the principle of common but differentiated responsibilities and respective capabilities, in light of different national circumstances.”  In other words, developing countries such as China continue to stress equity in insisting that they be given the same opportunity to develop, using fossil fuels for energy, that industrialized countries have benefited from for more than a century.  At the same time they point to the responsibility of those developed countries now to limit their emissions because of their advanced economic status.  These attitudes stress hindsight or past history.

Developed countries such as the U. S., on the other hand, presumably consider equity as supporting a policy that, since developing countries are now the ones expanding the world’s burden of atmospheric GHGs, they should bear the “differentiated responsibility” of constraining their emissions. Whereas China was an impoverished developing country in the early 1990s, it is now the world’s largest emitter of GHGs and a powerful economic force.  One can legitimately question whether developed countries still have to acknowledge “differentiated responsibilities and respective capabilities” of flourishing countries such as China.

Conclusion

U. S. President Obama and China’s President Xi announced bilateral objectives of differing scope and timing to place their nations on paths toward significant reductions in GHG emission rates.  The joint objectives mark the first time the two nations of the world with the highest emission rates agree on the importance of mitigating emission rates; the result will be highly significant for the climatic health of our planet.  Citizens of both countries, indeed of all the world’s nations, will benefit from this undertaking.  It creates an important incentive for achieving agreement on mitigating emissions worldwide, resulting from U. N.-sponsored negotiations over the coming year.

© 2014 Henry Auer

Monday, December 27, 2010

China and Global Warming: Past Growth and Future Trends

Summary:  The world is grappling with growth in atmospheric concentrations of greenhouse gases arising from burning of fossil fuels over the last 150 years.  The increased amounts of greenhouse gases are thought to be responsible for global warming. 

In this post we characterize the growth in the use of energy in the People’s Republic of China since the beginning of its market-based economy in 1978, practically all of which has been generated from the burning of fossil fuels that produce greenhouse gases. Here we summarize certain projections of China's future energy demand and its production, and conclude with an analysis of its stated policies concerning global warming.  A companion analysis for the United States is presented in the next post.  

Introduction:  China is the most populous nation in the world.  Yet, as the Table below shows, it is a developing country economically, as its per capita GDP for the year

Nation
Population 2008, millions
Est. pop. 2050, millions
GDP, US$, billions, 2008
Rate of growth of GDP 2003-8, %
Per capita GDP, US$, 2008
China
1,336.3
1,417
4,327
10.9
3,238
Philippines
89.7
146
167
5.5
1,860
U.S.
308.8
404
14,093
2.4
45,608
France
61.9
68
2,857
1.8
46,160










Source: The Economist, Pocket World in Figures, 2011 Edition, Profile Books, London, 2010.

2008 reveals.  It can be grouped with another developing country, chosen here to be the Philippines, as having a low per capita GDP value.  These countries may be contrasted with developed countries such as the United States and France, both members of the Organization for Economic Cooperation and Development (OECD), whose per capita GDP numbers are almost 15 times greater than that of China.  These numbers show that as China continues on its path toward further development, its GDP, and its per capita GDP, could expand by an order of magnitude.

The graphic below shows just that path of expanding GDP in China over the past 50 years, charted here up to 2005.  It is apparent that GDP has been expanding rapidly since 1978, when market-based economic reforms were begun.



Source: http://upload.wikimedia.org/wikipedia/commons/b/b3/Prc1952-2005gdp.gif. Permission for copying granted on Wikimedia. The exchange rate was 8.27 yuan per US$ from 1997 to 2005 (http://en.wikipedia.org/wiki/Renminbi).

Such rapid economic growth can only be undertaken by the use of corresponding increases in energy use.  To the extent that China’s energy needs are filled by burning fossil fuels, its economic growth results in corresponding increases in greenhouse gas emissions.  This post explores the energy landscape of China at present, its predicted continued expansion in future decades, and its impact on resolving the urgencies imposed on the world by global warming.

Overview of Current Energy Production in China

China has embarked on a vast program to expand its economy and bring material benefits to large segments of its population (U.S. Energy Information Administration (USEIA)).  From 2000 to 2009 its economy expanded by about 10% per year, and in early 2010 it grew at an annual rate of 11.9%. 

The Wall Street Journal on July 18, 2010 cited the International Energy Agency as reporting that China has become the world’s largest consumer of energy, outstripping the U. S.  China’s energy use has grown dramatically over the past two decades, as it has rapidly expanded its economy and developed new energy-intensive industries as well as constructed extensive new infrastructure projects (see the previous graphic and the graphic below). 


Source: International Energy Agency.  Format © The Wall Street Journal (http://online.wsj.com/article/SB10001424052748703720504575376712353150310.html?mod=googlenews_wsj#project%3DCHENERGY0719%26articleTabs%3Dinteractive).  Total primary energy consumption in million tons of oil equivalent for 2000-2009; 2009 estimated.  Rose bars, U. S.; yellow bars, China.

Producing steel and cement requires the input of large amounts of heat energy.  In 2009 China consumed 2.3 billion tons of oil equivalent energy, which includes energy derived from all fossil fuels as well as renewables such as hydropower and wind, and nuclear energy.  In contrast, the overall usage in the U. S. was 2.2 billion tons of oil equivalent.  The U. S. has been the highest consumer of energy throughout the 20th century.  As recently as 10 years ago, China’s consumption had been only half that of the U. S. In the interim, consumption by the U. S. has remained essentially constant, and even declined slightly in 2008 and 2009 as the economic recession took hold  (see the graphic).

Nevertheless, as a reflection of the per capita GDP data in the Introduction, the per capita energy use in China is far lower than in the U. S. (see the following graphic).


Source: International Energy Agency.  Format © The Wall Street Journal (http://online.wsj.com/article/SB10001424052748703720504575376712353150310.html?mod=googlenews_wsj#project%3DCHENERGY0719%26articleTabs%3Dinteractive).  Total primary energy consumption per capita in metric tons of oil equivalent for 2000-2009; 2009 estimated. Rose bars, U. S.; yellow bars, China.

The trend in China is increasing over the decade shown whereas that for the U.S. is steady or even declining in 2008 and 2009.

The distribution of fuels that provided the energy consumed by China in 2008 is shown in the following pie chart.  It is seen that coal provides by far the largest portion of China’s energy needs, as of 2008.


Source: U. S. Energy Information Agency (http://www.eia.doe.gov/cabs/China/Background.html).

Energy Production in China: Coal

China became the world’s highest emitter of CO2 and other greenhouse gases in 2007, surpassing the U. S. (Wall Street Journal, July 18, 2010) This is due to China’s heavy reliance on coal-fired electricity generation, and the fact that burning coal emits much more CO2 per unit of energy produced than any other fossil fuel. 

China’s newer coal-fired electricity plants are cheap, and burn more cleanly than earlier.  The new “supercritical plants” emit about 15% less CO2 than conventional ones, and cost about half the level prevalent in OECD countries ($500-$600 per kW (Reuters, 30 August 2010).

According to the Pew Center on Global Climate Change, coal costs about 1/6 as much per amount of heat produced on burning as does oil or natural gas, and China has vast deposits of coal.  Thus China has a strong incentive to continue using coal as a major source of its energy supply.  In 2006 China built new coal-fired plants with a total capacity of over 90 GW, or almost 2 large-capacity plants per week.  Just these newly-built plants emitted  13% of China’s 2006 total coal-fired greenhouse gases, adding about 500 million tons of CO2 to the atmosphere per year.

According to the U. S. Energy Information Agency (USEIA), China consumed an estimated 3.5 billion short tons of coal in 2009, (see the graphic below) which constituted 46 percent of the world total; this was a 180 percent increase since 2000. As seen in the graphic, coal consumption has been increasing over the last nine years, which is mirrored as well in the level of coal production, estimated at almost 3.4 billion short tons in 2009.

 Source: USEIA (http://www.eia.doe.gov/cabs/China/Coal.html)


Energy Production in China: Oil


In 2009 China consumed about 8.3 million barrels of oil per day, of which 4.0 million was from domestic production and the rest was imported (USEIA).  In that year China moved up to become the second largest importer of oil in the world, just outstripping Japan.  The U. S. remains by far the largest importer, at 9.6 million barrels per day in 2009.  USEIA estimates that Chinese demand for oil will continue to grow, reaching 9.6 million barrels per day in 2011, and about 17 million barrels per day by 2035.  A significant portion of the imported oil originates in countries such as Saudi Arabia, Angola, Iran and Russia.

Energy Production in  China: Gas


Natural gas contributes only a small fraction, 3%, of China’s total energy consumption as of 2008. Both production and demand for natural gas has been expanding rapidly in recent years.  The country expects to expand gas production and power generation using natural gas going forward, and is building several combined cycle (more efficient) natural gas plants (USEIA).

Electricity Generation in China

Explanation of Units. The watt is a unit of power, i.e., the rate of producing or using energy in a standard period of time.  When watts are multiplied by the time elapsed, we get the total amount of energy produced or consumed; in electricity jargon this energy unit is a watt-hour, or W-h.  More convenient amounts of power generation are measured in thousands of watts, or kilowatts (kW), and billions of watts, or gigawatts (GW).  The total amount of energy produced or used over a period of time, is expressed in thousands of W-h, or kilowatt-hours,(kW-h, on a household scale), or in millions or billions of kW-h (on an industrial scale or higher).


As of 2008, China’s actual capacity for generating electricity from all sources was about 800 GW.  In 2009 the total amount of electricity generated was about 3,500 billion kW-h for the nation as a whole, for the entire year.  As the graphic below shows, about 82% of this originated from conventional thermal generators, i.e., coal-, oil-, or natural gas-fired power plants.  Hydroelectric power represented about 16%.  According to USEIA, FACTS Global Energy estimated that overall generating capacity reached 950 GW by the end of 2010, a 19% increase.  Electricity production and consumption have more than doubled since 2000.  USEIA predicts that by 2035, the total annual electrical energy produced will be 10,555 billion kW-h, more than 3 times the amount produced in 2009.  The graphic below shows the breakdown of sources for the electricity that China generated in the 20 year period 1989-2009. 



Source: USEIA (http://www.eia.doe.gov/cabs/China/Electricity.html).  Red, conventional thermal; blue, hydroelectric; yellow, nuclear energy; green, other renewables.
 
Wind

Wind power is the second largest source of renewable energy generation in China after hydroelectric power.  China is the world’s 5th largest producer of wind power.  Its wind generating capacity has roughly doubled each year from 2005 (USEIA).  The most favorable wind sources are in the barren regions of western China.  However, the power grid in this sparsely populated region lags far behind the generation capacity.  The consumers of this power are far from its source.  (Xinhua, September 21, 2010,  reported by the Manila Bulletin).

Solar

Dunhuang, in the northwestern Gansu Province of western China is the center of a burgeoning development of solar generation, as this region receives the most intense sunlight in China.  By 2012 it is expected that solar photovoltaic panels (silicon wafers) will generate 300,000 kW, and ultimately 10 million kW.  In addition, by 2012 50,000 kW of solar heat generation of electricity will be installed.  This is part of a major program to bring the less-developed regions of western China closer to parity with the more wealthy coastal regions. (Xinhua, September 21, 2010,  reported by the Manila Bulletin).

Nuclear

A small nuclear power capacity in China is represented by its 11 operational reactors, with 8 more under construction and another 8 being planned.  Uranium ore is available domestically and more is imported.  USEIA estimates that nuclear power contributed 2% of electricity produced in 2009, and will grow to about 6% in 2035.

Future Trends

USEIA estimates that coal consumption will continue to increase although its share of total energy will fall to about 62% by 2035.  China’s announced intention is to reduce carbon intensity (CO2 equivalents emitted per unit of GDP) by at least 40% from the level during 2005 by 2020; yet in view of the country’s large population and rapidly expanding economy it is expected that the total consumption of coal will nearly double to 112 quadrillion British thermal units over this time (see China’s Response to Global Warming, below).

In the 12th Five Year Plan covering 2011-2015 China expects to close many older, smaller and less efficient coal plants in favor of larger ones (USEIA).  Many of the new plants supplanting the coal plants will use natural gas.

The Chinese government has forecast that conventional thermal power generation will remain the prevalent source over the next 1-2 decades, at about 67% of the total.  This may be understood at least partly in view of China’s vast reserves of coal.  Thermal power generation capacity is estimated to increase from 650 GW in 2009 to 1,000 GW by 2020.  USEIA’s estimate is more conservative at about 810 GW in 2020.

Renewable and Hydroelectric Sources

China has set forth a goal of generating 15% of its total energy production from renewable energy sources (USEIA).  As noted above, currently 16% of China’s electricity originates from hydroelectric power, and this generating capacity is the highest in the world.  This will increase even more as the Three Gorges Dam and other new hydroelectric generating facilities are brought on line.
 
The International Energy Agency (IEA; not to be confused with the USEIA)  is an autonomous organization associated with the Organization for Economic Cooperation and Development (OECD).  The IEA recently published its World Energy Outlook (WEO) 2010, which analyzes present and projected world-wide production and consumption of energy over the period 2010-2035, and assesses scenarios for meeting various objectives for limiting the effects of global warming.  WEO 2010 formed the basis of an earlier post on this blog.  WEO 2010 presents forecasts of future greenhouse gas emissions and some indices of economic development, based primarily on the “New Policies Scenario” resulting from measures to be taken in response to the Copenhagen commitments of 2009 (nonbinding and inadequate though they may be).  WEO 2010 judges that under this Scenario CO2 emissions continue to rise, by 21% over the level of 2008; this “trend would make it all but impossible to achieve the 2 deg C goal, as the required reductions in emissions after 2020 would be too steep” (emphasis in the original).  Rather, what is needed, in the view of WEO 2010, is early adoption of more drastic steps to keep the atmospheric CO2 level below 450 parts per million, in order to restrain average global temperatures from increasing more than 2 deg C (3.6 deg F) above the level that prevailed before the industrial revolution of the 19th century (the “450 Scenario”).  This limit was agreed to at Copenhagen, and confirmed at the recent Cancun conference (see the post).

Under the New Policies Scenario, WEO 2010 predicts worldwide coal usage shown in the following graphic.  It is seen that the contribution predicted for China alone is



a major part of the overall demand for coal. 

It is important to note that, in the preceding graphic, the contribution from coal, as well as from other fossil fuels not shown, provide annual increments to atmospheric CO2 once burned.  In a previous post the atmosphere was likened to a bathtub containing CO2.  These annual increments act to fill the bathtub even higher than it is today. Only zero increments, barring any compensating decreases, can keep the CO2 bathtub at a constant level.

China’s demand for all sources of energy is expected to continue growing at similar high rates in coming years.  These observations may be further visualized in the following graphic, which includes China’s share of projected changes in sources of energy demand (orange bars).


Reproduced from World Energy Outlook 2010 © OECD/IEA. 

The color scheme is the same as in the first graphic, above.  The bars for coal and oil to the left of the “0” line represent decreases in usage for these fuels over the period 2008-2035 in the OECD countries.  Bars to the right of the “0” line represent increases in usage.  Single-handedly China (orange) accounts for profound increases in demand for fossil fuels over this period, as well as for renewable sources of energy.  Mtoe, energy demand (consumption) expressed as equivalents of millions of tons of oil.

China’s Response to Global Warming

China’s policy in response to global concerns about the buildup of greenhouse gases, and the resulting global warming, has been to emphasize reduction of carbon intensity rather than actual quantities of greenhouse gases emitted.  Carbon intensity represents the rate of emission of greenhouse gases per unit of gross domestic product (GDP), a measure of overall economic activity of a country.  China’s policy is to reduce the carbon intensity by measures such as making use of fossil fuels more efficiently and expanding the use of renewable energy, hydroelectric generation and nuclear energy.  According to the Wall Street Journal of July 18, 2010, China has established a target of reducing its carbon intensity by 40-45% below the level that existed in 2005 by 2020.  Historically China has not subscribed to the view, put forward by the world’s climate scientists, and by other nations of the world, that it has to work toward reducing the absolute amount of greenhouse gases emitted.  Yet, as these scientists point out, it is the total amount of greenhouse gas emissions that must be controlled, indeed controlled quite drastically, to attain the reductions needed for the WEO 2010 450 Scenario.  Otherwise, as China continues its industrialization and the urbanization of its population, demand for total energy production will increase many-fold.  This may be seen, for example, by the great disparity between the per capita energy consumption between the U. S. and China, illustrated earlier in the third graphic above.

It should be noted, nevertheless, that perhaps China may be changing its approach to reducing global warming. In a press conference webcast from the Cancun climate conference held Nov. 29-Dec. 10, 2010, the representative of the People’s Republic of China, Xie Zhenhua, emphasized China’s progress in limiting its carbon intensity.  In the current (11th) 5-year plan, carbon intensity has diminished by 20%.  In response to a question, Mr. Xie summarized China’s position that the industrialized nations have already attained high levels of economic prosperity, whereas China is still a developing country with a high level of poverty and increasing extents of urbanization still proceeding.  Nevertheless, he stated that China is building into the next (12th) 5-year plan a goal of reaching a peak in carbon emissions (implying a subsequent decrease).  This statement may reveal an appreciation of the need to address total greenhouse gas emissions rather than carbon intensity.


© 2010 Henry Auer