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Growth in Use of Energy
China has large reserves of relatively high quality coal
(approximately 1.04% sulfur with about 10% ash content) although in some
areas the most readily available coal may have sulfur as high as 5% (Smil,
1996). Large electrical generating plants have been constructed and more
are being planned to power several large industrial areas that are leading
the way for Chinese development. Medium-technology pollution control
equipment is available and being installed in newly constructed plants.
However, these devices are not always functioning properly, and
provincial
regulatory agencies have little authority to enforce existing laws
governing their operation. Compounding the problem are inefficient
combustion processes in residential and small commercial applications which
lead to high levels of sulfur dioxide and particulate matter despite use of
relatively high quality fuel. Individual homes in
undeveloped regions burn charcoal
briquettes for heating and cooking.
Oil is less abundant in China, and recent efforts to intensify exploration have proved to be disappointing (Drennen and Erickson, 1998). As a result, China began importing oil in 1993 and within two years was purchasing 400 thousand barrels per day on international markets. This doubled to 800 thousand barrels per day in 1997 and is projected to reach 7-8 million barrels per day in 2015 and 13-15 million barrels per day by 2025. The US, by contrast, imports 8.4 million barrels per day.
Nuclear power contributes a small fraction to China's energy supply. China has substantial hydropower potential, much of which remains untapped. Solar and wind energy have not been exploited. Biomass has seen limited use for energy, although multiple (double and in some cases triple) cropping patterns, with resulting requirement to remove dead plant material for replanting, would seem to offer potential for future growth of biomass for fuel. Drennen and Erickson (1998) assert that, even under optimistic scenarios of foreign investment in hydro, nuclear, and biomass, the primary energy supply in China in 2025 will be fossil fuels (68% coal and 25% oil).
The environmental consequences of China's rapid increase in the use of fossil energy include increased concentrations of sulfur dioxide gas (and subsequently sulfate particles), which, together with oxides of nitrogen provide the ingredients for acid rain. The relatively inefficient combustion produced in some industrial applications and in all coal briquette-burning stoves in private homes produces carbon monoxide and unburned hydrocarbons that create the growing smog problem in most major cities. And, of course, all use of fossil fuel leads to the release of fossil carbon into the atmosphere as part of the increase in greenhouse gas loading.
Foell et al (1995) have evaluated impacts on ecosystems in Asia resulting from sulfur dioxide emissions from energy use. With a "business as usual" approach to energy growth and emissions control in Asia, sulfur deposition will rise to 2-5 g m2 y-1 by 2020. Peak depositions in industrial areas of China are projected to be as high as 27 g m2 y-1, approximately twice the worst cases experienced in Central and Eastern Europe. Impacts on ecosystems are evaluated by comparison against the critical load (CL), defined as the highest load that will not cause chemical changes leading to long-term harmful effects in the most sensitive ecological systems (Kuylenstierna and Chadwick, 1989). Calculations of Foell et al (1995) revealed that CL of sulfur will be exceeded over large regions, including many productive agricultural regions, by 5-10 g m2 y-1. By use of the RAINS software (Kamari et al, 1989) we produced a plot of percentage of areas in each 1o x 1o grid box that exceeds the CL for Asia for the year 2020 if no sulfur control strategies are employed (Figure 1). Figure 2 gives the sulfur exceedance amount for each region identified in Figure 1 as exceeding the CL. The urgency of the problem is confirmed by the fact that the pH of rainfall in Liuzhou in Guangzi Province has been reported to be 3.06, and Guiyang in Guizhou Province has reported rainfall of pH 3.15 (Smil, 1996b). (Seven is neutral and less than 7 is acidic.) For comparison, this rainfall is more acidic than a tomato (4.0 - 4.4) or a dill pickle (3.2 - 3.6) and approaches the acidity of pure vinegar (2.4 - 3.4).
Impacts of tropospheric ozone and other air pollutants associated with both stationary and mobile energy consumption are expected to produce additional strain on ecosystems.
NEXT: Growth and Change in Food Demands