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4. Reducing Greenhouse Gas Emissions from Generating Electricity
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4 Despite the considerable progress made in improving the energy efficiency of the US economy, emissions from generating electricity continue to be a major contributor to GHG levels. Although the economic downturn that began in 2008 has reduced the overall growth rate, electricity demand is projected to rise by just over 30 percent over the next quarter century (US Department of Energy, Energy Information Administration, 2011c). Rising demand for electricity is a problem because coal is the dominant fuel for generating electricity in the United States, and it is dirty. In fact, coal is the single largest source of GHG emissions and is also a major source of conventional air pollutants, including fine particulates , that are most harmful to public health. Coal is king because it is an efficient and plentiful fuel and domestic supplies make it very attractive amid the debate over energy security. Shifting to alternative fuels will be expensive because of the investment reflected in the coal-fired plants currently operating and because burning coal in these plants is still the cheapest way to produce electricity on a large scale. Despite its low cost, however, beginning the transition away from coal is essential because coal combustion produces more GHG emissions per unit of energy generated than any other fuel. Coal is responsible for the lion’s share of CO2 emissions from electricity, accounting for more than 81 percent. Natural gas produces 17.3 percent, and petroleum is responsible for about 1 percent (US EPA 2011e). Because burning coal also produces pollutants that contribute to acid rain, urban air pollution that threatens public health, and toxic mercury emissions, there are significant co-benefits that would follow from either clean air or climate policies. And because many of the same processes produce CO2 and conventional pollutants, clean air policies can also reduce GHG levels. But there are also perplexing trade-offs: control equipment aimed at reducing particulates, responsible for the most Reducing Greenhouse Gas Emissions from Generating Electricity 72 Chapter 4 serious public health threats from air pollution, also reduces the efficiency of power plants, thus requiring that more fuel be used and leading to higher CO2 emissions. Although coal has clear environmental disadvantages, there is currently no clear alternative to replace it immediately. Lower prices and a dramatic increase in supply due to hydraulic fracturing (also known as fracking) have made natural gas an option but the chemicals used in fracking have raised concerns about contamination of drinking water. Nuclear power is also an option, given the generating capacity of large nuclear units, but that would require a massive investment in new plants and would only magnify the problem of waste storage and safety concerns . Renewables such as wind, hydro, and solar are certainly cleaner than coal and natural gas, but they are either not yet economically competitive or available on a wide-enough scale to displace fossil fuels. Coal also has powerful allies in Washington, making it difficult to chip away at policies that support its use. Perhaps most important, power from coal is cheap and proponents support its continued use in order to keep energy prices as low as possible. For all these reasons, reducing emissions from coal is an immediate climate policy priority even as policies chart the long-term transition from coal to cleaner fuels. There are three primary ways of reducing GHG and other emissions from coal-fired power plants: (1) changing the way in which coal is used to produce electricity, (2) improving the efficiency of the production and use of power so that less electricity needs to be generated, and (3) shifting to cleaner, alternative fuels. If we are going to make significant progress in reducing emissions, we will need to pursue all three. This chapter begins with a brief discussion of GHG emissions from electricity generation, particularly carbon dioxide, and then examines options for reducing our reliance on coal in order to pursue climate change, air pollution, and other related policy goals. Throughout this chapter, the underlying issue is how integrating energy, climate, and air pollution policies helps frame the policy issues and choices. An Overview of US GHG Emissions from Electricity Electricity generation, transmission, and distribution were responsible for the largest share of greenhouse gas emissions (33 percent) in the United States in 2009, followed by transportation (27 percent) and industry (20 percent) (US EPA 2011e). If electricity emissions are distrib- [44.204.117.57] Project MUSE (2024-03-29 16:58 GMT) Reducing Greenhouse Gas Emissions from Generating...