JACK J. FRITZ
National Academy of Engineering
Energy use and air pollution have been synonymous in China for decades, especially in urban areas. In rural areas, air pollution is also common because a significant amount of industry that is highly dependent on coal is located in the countryside. Fifteen or 20 years ago in China’s northern cities, such as Shenyang, air pollution was characterized by decreased visibility caused by high levels of particulates and sulfur dioxide (SO2). Although conditions have improved in modern cities, such as Beijing and Shanghai, China still has three of the ten most polluted cities in the world and hundreds of cities that are not in compliance with the World Health Organization (WHO) air quality guidelines.
China is undergoing urbanization and industrial development on an unprecedented scale. More than 120 cities have populations of more than one million, and by the end of the twenty-first century, 10 to 20 cities will have populations of more than 10 million. Rapid urbanization will challenge governments at all levels, not only to provide basic services to growing urban populations, but also to modernize, to continue to develop economically, and to address environmental concerns, particularly air pollution, that result from rapid economic growth.
In October 2003, a group of experts met in Beijing under the auspices of the Chinese Academy of Sciences, Chinese Academy of Engineering, and National Academy of Engineering (NAE)/National Research Council (NRC) of the National Academies to continue a dialogue and eventually chart a rational course of energy use in China. The importance of pollution abatement as part of an energy policy, a fairly recent idea in China, is already a major theme in national planning. In fact, in response to growing clamor for change by an increasingly
prosperous and involved public, pollution reduction has been singled out as a priority in China’s Agenda 21 document.
Chinese planners now recognize that the choice of energy supply affects not only public health, but also land use, the environment, infrastructure, services, and economic growth. Thus, a secure, flexible, and varied energy-supply policy is critical to continued growth. Because China has an overabundance of coal and a scarcity of oil and gas, planners must continually balance the public good (i.e., public health and quality of life) against the easy availability of polluting coal and the high cost of importing oil and natural gas. Fundamentally, the Chinese policy community must address ambient air quality concerns by integrating energy supply and use for all economic sectors—industrial, power generation, residential, commercial, and transportation.
A good deal of progress has been made in China since the mid-1990s. The national averages for emissions of SO2 and particulate matter (PM) have decreased, mostly as a result of stepped up enforcement of existing standards by national, provincial, and municipal governments. However, because of the increase in vehicle pollution and the continued prevalence of fine-particle pollution (less than 10 microns [PM10], or even 2.5 microns in diameter [PM2.5]), the government passed a second amendment in 2000 to the 1987 Law of Air Pollution Prevention and Control. The new legislation, which went into effect September 1, 2001, calls for the regulation of transportation, as well as residential and commercial energy use. When the new law is fully implemented over the next decade, it will greatly strengthen environmental laws and standards.
One purpose of the October 2003 meeting was to identify trends that will influence future energy choices in China. These trends are discussed below.
The Presence of Fine Particulates (PM10 and PM2.5)
In response to increased vehicle density and traffic congestion, China is implementing new control systems on combustion engines in cars, trucks, and small vehicles with two-cycle engines in hopes of reducing ground-level ozone and suspended particulates. To determine the effectiveness of these measures, China must first improve its monitoring of PM2.5 and PM10, as well as of gases, such as ozone. In a detailed report on source apportionment by Zhang et al., the authors note that their monitoring studies show the smallest particles in Beijing are predominantly from stationary sources (e.g., coal combustion and fugitive dust) rather than vehicles, despite the increase in vehicular traffic. This may be because vehicles in Beijing tend to be new and have fairly efficient combustion systems. This conclusion is affirmed by Xu et al. in their discussion of the power sector. The authors of both papers conclude that the monitoring and analysis of
PM and gases should be improved to ensure that policy makers have accurate data on the amount and sources of pollution. A related paper by Bergin adds that high aerosol loadings decrease visual range and attenuate solar radiation, which may result in decreased crop yields in nearby rural areas.
Chow and Watson discuss problems with sampling techniques and the unreliability of conclusions based on incomplete data. They also note the relationships between combustion-related particulates, fugitive dust, and precursors. For example, it has been widely assumed that the source of much of the PM in Xian is the desert west of the city. However, sampling reveals that PM is mostly from combustion sources and local dust, such as unpaved roads and empty tracts of land. Based on this information, policy makers can now develop a more effective, locally based strategy for controlling pollution in Xian.
Substituting Natural Gas for Coal
Natural gas is widely considered a viable replacement for coal, both for industry and home heating. But natural gas is expensive and not easily available in Chinese cities. In addition, further research will be necessary before vehicles that run on natural gas can be developed and before coal-fired heating boilers can be converted to natural gas.
Therefore, the Chinese government is committed both to the development of cleaner coal technology and to reducing the country’s dependence on coal. Coal combustion continues to be the largest contributor to air pollution in China, with particulates and SO2 causing the most significant problems. Although emissions of SO2 and particulates have declined in some major cities since the mid-1990s as a result of improved controls and the increased use of low-sulfur coals in the power sector, emissions of both pollutants must clearly be reduced further. However, it is not obvious how this can be done economically. China needs a full analysis of SO2 reduction under various control and policy strategies across various economic sectors. Xu et al. describe several control scenarios (with the required investments) for the power sector.
Xu et al. and Fritz both argue that coal will continue to be the dominant fuel for the next 50 years and that a variety of new technologies will be necessary to mitigate the negative environmental effects of coal consumption. These authors present a sober, realistic assessment of the difficulty of making a rapid transition to natural gas and renewable energy.
Based on the expectation that coal use will not only continue, but will even increase, Jin et al. make a strong case for the development and implementation of integrated gasification combined cycle (IGCC) with carbon dioxide (CO2) sequestration technology for power generation from coal. Fan and Yu provide a detailed look at the composition of the energy supply in China and urge local authorities to increase energy efficiency, use advanced technologies, and diversify the fuel mix.
Vehicular Emissions of Nitrogen Oxides, Carbon Monoxide, Ozone, and Lead
NAE/NRC and the Chinese Academy of Engineering published a study in 2003 on the impact of the growing number of private automobiles in China. The study offered several recommendations for coping with the increase in pollution and congestion, but did not include a detailed plan. The report also documented some steps that had already been taken. For example, as of July 2000, leaded gasoline has been banned, starting in Beijing. However, emissions of nitrogen oxides (NOx), carbon monoxide (CO), and ozone (O3) from vehicles continue to increase. If, as expected, the number of vehicles increases dramatically, new regulations will be necessary just to maintain current air pollution levels and avoid the formation of smog.
Based on a consensus of the estimated number of vehicles in China in the coming years, Walsh offers recommendations for the development of clean, energy-efficient vehicles. This is the only way, he argues, China can address the inevitable increases in pollution from the addition of millions of vehicles, even if they are new, more efficient vehicles.
Sperling and Lin discuss air pollution from a mode of transportation unique to China, Chinese rural vehicles (CRVs), which outnumber conventional passenger vehicles by 3 to 1 and are extremely inefficient. The challenge for the Chinese government is to develop policies that mitigate the negative environmental impacts of these vehicles while promoting their economic benefits. Yan and Wen outline an electricity-based approach to the problem of urban transportation. They highlight recent technological advances in electric rail, electric vehicles, and high-speed magnetic-levitation (maglev) trains and describe their benefits.
Pollution in Small Industrial Cities
Perhaps the most challenging problem facing urban China is how smaller, coal-based, industrial cities can manage air pollution. Prosperous cities, such as Beijing and Shanghai, have enough resources to make radical changes in their energy mix. But most people live in mid-sized cities that do not have the resources to make radical changes. Tang describes some characteristics of air pollution in these cities brought about by rapid economic growth.
Smaller cities have experienced increases in SO2, TSP, and NOx levels as the result of their overwhelming reliance on coal for residential and industrial uses. Data on trends in levels of CO, O3, and lead are not available for many small cities.
Reducing Sulfur-Dioxide Emissions and the Long-Term Implications of Acid Rain
Levels of acid deposition in China, like levels of SO2 emissions, have decreased slightly since the mid-1990s. Nevertheless, as Kan et al. point out in their paper, acid rain remains a dangerous problem, particularly for human health. The major method of reducing SO2 emissions has been to require that power plants use cleaner, low-sulfur coal and install flue-gas desulfurization technology. Although reductions are progressing reasonably well in the power sector, SO2 emissions from state-owned industries are essentially unchanged.
Air-quality control at state-owned facilities remains a challenge. Many state-owned enterprises are not only outdated and uncompetitive, but are also financially stressed. Requiring stricter air-pollution compliance for these enterprises would force many of them into bankruptcy. Exacerbating the financial situation of these enterprises is the need to maintain a safety net for labor. Even though many of these industries are being restructured and the facilities sold off, serious questions about their future environmental impacts have yet to be addressed.
Guttikunda et al. describe a model that has been used to predict increases in SO2 levels from the transport of emissions from new stationery sources in Asia. The model provides an inventory of large sources based on a grid size of 80 km by 80 km. Today, new investments in power-generating facilities, for example, must be run through the model to determine their impact and transport potential before they are approved. In neighboring Japan, this type of analysis is used to confirm local measurements of acid-rain deposition, a major concern.
Along similar lines, Levin describes the long-range transport of air pollutants and approaches for tracking them spatially and temporally across the Pacific Ocean. Mercury is used as a tracer substance, or proxy, for other pollutants, because it results from coal combustion and tends to be conservative.
Need for Improved Monitoring
Current and past techniques for measuring air pollution have often led to inaccurate results. It is unclear how, or if, these results have been used in setting policy and determining compliance, but China has no quality assurance programs in place to determine the accuracy of measurements or the condition of sampling instruments. Two papers, one by Chow and Watson and one by Zhang et al., address these problems. The authors of both papers conclude that an in-depth evaluation of equipment and methods should be undertaken, followed by an assessment of methods of data analysis and interpretation.
Positive Trends in Controlling Power-Sector Air Pollution
China has made significant progress in controlling pollution from the power sector, which now has many modern, state-of-the-art plants. Fritz argues that strict environmental oversight by the World Bank as a condition of loans to the power sector has brought pressure to bear on local environmental authorities to control emissions and procure state-of-the-art, pollution-control equipment. Questions remain, however, as to whether power-plant operators will continue to use the equipment. We know, for example, that in the cement industry, electrostatic precipitators are not used except when a monitoring cycle begins. Another problem is that policy makers lack a fundamental understanding of the fraction of ground-level air pollution that comes from the power sector and how much comes from small boilers. Most new power plants have stacks more than 200 meters high for wide dispersal, which makes it difficult to measure their contributions to ground-level pollution.
Emerging Regulatory Processes
The regulatory environment and compliance monitoring are the cornerstones of a system that can force polluters to reduce emissions. The paper by Wang and Wu addresses some of the institutional issues involved and introduces the reader to the Chinese regulatory framework. Although improvements in the current regulatory framework were not discussed in depth at the workshop, the group did reach a consensus that some of the techniques used in the United States might also be used in China, at least on a pilot scale. These include self-reporting, emissions trading, and tax-related incentives, coupled with tough enforcement.
Scale and Financial Impacts of Air Pollution on Public Health
The public health impacts of pollution are just beginning to be known. Some studies of hospital data and labor productivity have been undertaken, but at this point, the only conclusion that can be drawn is that the cost to the country and the Chinese people is enormous. Kan et al. take a preliminary look at methodologies for assessing health issues.
Whipple describes studies based on air-dispersion modeling of key sources in the United States to determine exposure to toxic substances emitted by power plants, such as mercury, arsenic, chromium, etc. To date, however, these studies have not provided a full accounting of health effects for these airborne species. Chinese authorities are monitoring U.S. progress in this area and are expected to adopt this type of monitoring in the coming years.
Emerging Technologies for Energy Generation and Distribution
As modernization in China continues, the private sector is looking for opportunities to become involved in power generation and distribution. Although China is still far behind other developing countries in opening the power sector to private operators, Feng and Wang describe a trend toward providing electricity, heating, and cooling power to new commercial ventures via cogeneration and distributed-energy systems. The trend is especially prevalent in private retail, industrial, and residential developments around Beijing and Shanghai. Fan and Yu identify areas for improvement, including the use of advanced power generation, combined heat and power generation (CHP), and non-coal fuel sources.
This collection of papers is intended to introduce the reader to the complicated problems of urban air pollution and energy choices in China. The positions of the authors do not represent official government policy or a consensus on best approaches. They do reflect recent thinking on the subject by individuals familiar with the issues. But we have only made a start, and much work remains to be done to bring additional Chinese and U.S. participants into the discussion.
The development of energy policy in China is important not only for China but also for the United States, Russia, India, and the European Union (EU). Each country or region has special concerns and limited “wiggle room” in terms of energy resources and economic resources, and each must make trade-offs between pollution abatement and costs. Clearly the United States and EU are better able on a per capita basis to shoulder these burdens than developing countries, which need cheap energy to move forward. Developed and developing countries have much to learn from each other. We hope that this gathering of experts on air pollution and energy will be the first in a series of interactions in the coming years.
Chinese Academy of Engineering, National Academy of Engineering, National Research Council. 2003. Personal Cars and China. Washington, D.C.: The National Academies Press.
National Research Council, Chinese Academy of Sciences, Chinese Academy of Engineering. 2000. Cooperation in the Energy Futures of China and the United States. Washington, D.C.: National Academy Press.
World Bank. 2001. China: Air, Land, and Water. Washington, D.C.: World Bank.