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Buildings use energy. In fact, buildings account for about one-third of U.S. energy generated by fossil fuel resources. However, there are further fuel resources that are consumed by buildings. The inherent acts of construction, operations, and maintaining the infrastructure of buildings use energy. But at what cost? How does this affect us and the landscape around us? What can be done to mitigate our energy use?
Heating, Cooling, Lighting, and Power
The majority of building energy consumption is from the need to provide heating, cooling, lighting, and power distribution. Nearly all energy production for buildings, an estimated 96 percent, is generated off-site and transferred, shipped, or pumped to the building’s locale. Of this off-site energy, an estimated 82 percent is derived from fossil fuel resources in the form of oil, natural gas, and coal. This energy production in the United States accounts for nearly 80 percent of air pollution, more than 88 percent of greenhouse gas emissions, and more environmental damage than any other human activity.
Climate Change
A recent study estimates that greenhouse gas emissions increased by an estimated 23 percent between 1987 and 1996 to 939 million tons. In 1996, 43 percent of the greenhouse gas emissions came from electricity generation, 20 percent from transportation, and 29 percent from mining, refining, manufacturing, and construction industries combined. The use of coal for electricity generation and heat production is the largest single source of carbon dioxide emissions in the United States, contributing a total of about 344 million tons of carbon dioxide in 1990, or about 28 percent of the carbon dioxide emitted. More than half the electricity generated in the United States is through the use of coal. Each megawatt-hour of electricity sourced from black coal–fired generators produces about 1,665 pounds of carbon dioxide, a major greenhouse gas.
Air Pollution
In 1992, power stations accounted for an estimated 35 percent of nitrogen oxide and 60 percent of sulfur dioxide emissions in the United States. Emissions from petroleum refineries account for about 37 percent of the volatile organic compounds emitted by major industrial and commercial sources. Trends in recent years show small increases in total emissions; however, there have been large reductions in particulate emissions because of the improvement in filter technology and reporting methods.
The impact of coal mining on the environment includes coal seam methane drainage into the atmosphere and dust created by mining operations. Energy industries incur significant operating and capital expenditures to reduce air and water emissions, translating into cost increases for the consumer.
Water Pollution and Waste
The production, transportation, and storage of fuels can have significant effects on surface and underground water bodies. There are concerns about the leaking of underground storage tanks, disposal of used transformer oil, and coal washery waste discharge (an estimated 89.2 million tons in 1995).
Habitat Disturbance and Aesthetics
The impact of coal mining on the environment includes disturbance from mining operations. Energy distribution systems for both electricity transmission lines and oil and gas pipelines can cause serious habitat disturbance and be aesthetically unpleasant. Electricity is transmitted and distributed via a large network of lines. An unfortunate result from off-site energy generation is the inefficiency of our transmission lines. Nearly one-third of energy produced is lost in transmission alone. The length of high-voltage lines increased by 39 percent from 1979 to 1995. Most lower voltage lines are also overhead, with an increase of 33 percent in the same time period. There is considerable community concern about the health and amenity impacts of high-voltage transmission lines. Discussion on electromagnetic fields and telecommunications cabling affecting the health of children living in close proximity continues in the court system.
Nuclear Electric
An estimated 22 percent of the U.S. electricity generated is from nuclear power plants. Emissions of these plants are much lower than those of fossil fuels; some studies report they are as much as 80 percent cleaner. Greenhouse gas and carbon dioxide are also greatly reduced. Debate continues over the disposal of the radioactive waste resulting from nuclear generation and perceived threat to neighbors. Mining and extraction of core radioactive fuel as well as transportation and storage continue to raise concerns.
Hydroelectric
Hydroelectric power accounts for approximately 10 percent of the U.S. electric generation. With few to no emissions resulting from power generation, hydroelectric facilities affect primarily their immediate surroundings. Damming requires a significant amount of land. This land acquisition displaces wildlife habitats, ecological diversity, and often watersheds, which inevitability affects local human development and resources. Flooding caused by hydroelectric generation creates concentrations of algae and decay from vegetation, resulting in limited greenhouse gas generation, but the most immediate hazard is the possibility of failure of the dam itself. Most of the negative environmental impacts of large-scale hydroelectric installations can be avoided by the installation of small-scale hydroelectric systems. Small-scale systems provide much less power (typically a single site up to a regional or provincial power grid) and require a sizable flow of water on-site to prove economically viable.
Wind Wind
Wind
Wind
Although only an estimated 2 percent of the total electricity generated in the United States is from wind power, wind generation is gaining popularity, with nearly a 78 percent increase from 1998 to 2005. Inefficiency and noise pollution problems of older technologies have prevented installation of systems in the past, whereas current systems offer much improved solutions.
Solar
In the United States, less than 1 percent of electricity is generated using solar technology. With a huge surge in the mid-1970s, solar power had nearly vanished from the energy market in the United States until the late 1990s. With limited efficiencies, expensive up-front costs, large system requirements, and caustic battery storage systems, solar power appeared to be the last choice for energy needs. However, in light of current and future fuel circumstances, solar is much more attractive. Solar panels are lasting longer, performing better, and are often subsidized with tax incentives. The 1970 cost of a photovoltaic watt was $100; it is now close to $4.
Ethanol and Biodiesel
Ethanol and biodiesel are recent additions to the fuel market, with reports of a 40–60 percent reduction in emissions of nitrogen, hydrocarbons, and particulates. Studies have shown that biodiesel is as much as 72 percent “cleaner” than tradition petroleum diesel. Despite critics’ claims that corn-based ethanol is fundamentally a bust (i.e., that it takes more fossil fuel to produce than it displaces in the fuel tank), the majority opinion within academia and industry is that ethanol and biodiesel do result in net energy gains. Most skeptics concede that if the balance isn’t positive now, it will be soon. Alternatives to corn-based ethanol include sugarcane, wheat, cotton, and switchgrass. Other nations currently use these alternatives, and it will be informative to watch the potential for environmental and social disruption. |