POWER SYSTEMS

Power systems represent the class of technologies used to generate electricity. The cost-effective generation, distribution, and use of electricity since the early twentieth century have changed ways of life in developed and developing countries alike. Electricity has made possible a special kind of economic and technological development, including conveniences at home and increased productivity at work. It is what drives modern society and is the foundation upon which the digital age is being built.

However electricity production has also had major impacts on the biosphere. The production of electricity, which is generated primarily from carbon-based fuels, has contributed largely to the increase in greenhouse gases. Electricity production is also responsible for acid rain and smog precursors, as well as mercury and other toxic air pollutants. In addition, two-thirds of electricity production globally is from nonrenewable resources. Thus an electrified society places future generations at risk by both destroying the biospheric services on which they depend for survival, and depleting natural resources. If one accepts a moral obligation for the health and happiness of future generations, the current power system model should be reconsidered.

Production Developments

A curiosity before the 1880s, electricity entered the mainstream in 1882 when Thomas A. Edison began generating and distributing direct current (DC) electricity from his Pearl Street station in New York City. This was soon followed by a host of other generation and distribution systems, most notably by George Westinghouse, who in 1895 began to produce alternating current (AC) electricity from a power plant at Niagara Falls. Soon after AC electricity became the dominant form used in homes and businesses. From 1900 through the 1930s, new appliances, such as vacuum cleaners, washing machines, refrigerators, radios, and televisions, found their way into U.S. and European homes; the Electric Age had begun.

The first electric power plants burned coal or wood to produce steam to power electric generators. In the United States and Europe fossil fuels dominated power markets throughout the first half of the twentieth century. For example, in the United States in 1950, production of electricity from coal, oil, and gas was 46 percent, 10 percent, and 13 percent respectively, while hydroelectric dams produced about 30 percent of the total.

In the 1960s, nuclear power was harnessed to generate the heat needed to power steam turbines. In the early twenty-first century in some countries, such as France, nuclear power contributes a majority of electricity. In the United States, fossil fuels still dominate, as shown in Tables 1 and 2.

The electrification of the industrial world is almost complete. However many people in the developing world still live without electricity. As these nations develop, electricity will surely play an increasingly important role. Even with advancements in energy efficiency and flattened population growth projections, one would expect significant increases in electricity consumption in the developing world throughout the twenty-first century.

Electrification of highly populated developing countries, particularly China and India, may have significant global repercussions. If the electrification of these countries occurs using fossil fuels such as coal, there are grave concerns about the impacts on greenhouse gas emissions and global warming. Similarly, if these countries move toward a nuclear future, concerns about weapons proliferation, safety, and nuclear waste management present additional challenges.

Future Assessment

Those in the developed world cannot expect developing countries to forego electrification as they move along the development path. However technical solutions may exist to limit the global problems associated with electricity production. One such solution is renewable energy. Although new hydroelectric dam sites are becoming scarce, electricity opportunities from wind, solar, and biomass are increasing. Wind power is now competitive with fossil fuels in many areas, while solar

technologies are currently cost effective in some remote locations or niche applications. Issues such as energy storage and delivery currently plague these technologies, but with appropriate technological advancements and economic assistance, the developing world may be able to achieve a future that has eluded the industrialized world—carbon-free electrification.

Another energy source that looks promising and would support a renewable electric future is hydrogen. Because hydrogen can be produced from the electrolysis of water, one could envision a system whereby electricity produced from a renewable resource, such as solar photovoltaics, could be used to generate hydrogen. This hydrogen could be stored and transported, and ultimately used in fuel cells to produce electricity where needed. However, despite recent media attention on hydrogen and the so-called hydrogen economy, the current state of technology and costs suggest that hydrogen will not become a genuine competitor to fossil fuels before the mid-twenty-first century.

The development of carbon sequestration technologies may provide another solution to biospheric problems posed by carbon-based power systems. These technologies are able to capture carbon emissions from power plants and transform or store this carbon to prevent atmospheric discharge and greenhouse gas buildup in the atmosphere. Considerable research is also being invested in other ways to reduce carbon emissions from coal-fired power plants.

Ethical Issues

The ethical implications of power production rest on the seriousness with which society holds its responsibilities to future generations. Since energy markets cannot adequately internalize the costs of fossil-fuel power generation (both in terms of current and future environmental externalities), many argue that government policies

and international agreements are needed. However there is still uncertainty surrounding the distributional impacts of global warming (across space and time). This uncertainty has been used to thwart regulatory actions aimed at curbing carbon emissions from fossil-fuel power plants. Assuming continued uncertainty about the long-term impacts of greenhouse gas emissions, one would expect governments to be slow to take action in the near term. The development of marketable, cost-effective competitors to fossil fuels will likely be needed to displace early-twenty-first-century power systems. Thus far such technologies do not seem imminent.

JAMES J. WINEBRAKE

SEE ALSO Alternative Energy;Alternative Technology.

BIBLIOGRAPHY

Smil, Vaclav. (2003). Energy at the Crossroads. Cambridge, MA: MIT Press.

Winebrake, James J., ed. (2004). Alternate Energy: Assessment and Implementation Reference Book. Lilburn, GA: Fairmont Press.

INTERNET RESOURCES

Energy Information Administration. U.S. Department of Energy. Available from http://www.eia.doe.gov.

IEEE. (2005). "How Electricity Came to Be." Available at the IEEE Virtual Museum http://www.ieee-virtual-museum.org/.