The impact of global warming on the U.S. energy sector

In the Global Climate Change Impacts in the United States report, prepared by the U.S. Global Change Research Program (USGCRP) and a number of U.S. government agencies, warned that global warming would have significant impacts on the U.S. energy sector. In the chapter on Energy Supply and Use, the report notes that oil is primarily used for transportation fuels, gas is used "in roughly equal parts" for generating electricity, direct use in power industrial processes, heating water and heating buildings. "Coal is primarily used to generate electricity (91 percent of coal use)", it noted, while "nuclear power is used entirely for electricity generation."

Excerpts from the report
The report flagged that:


 * "Research on the effects of climate change on energy production and use has largely been limited to impacts on energy use in buildings. These studies have considered effects of global warming on energy requirements for heating and cooling in buildings in the United States. They find that the demand for cooling energy increases from 5 to 20 percent per 1.8°F of warming, and the demand for heating energy drops by 3 to 15 percent per 1.8°F of warming";


 * "Studies project that temperature increases due to global warming are very likely to increase peak demand for electricity in most regions of the country";


 * Since nearly all of the cooling of buildings is provided by electricity use, whereas the vast majority of the heating of buildings is provided by natural gas and fuel oil, the projected changes imply increased demands for electricity. This is especially the case where climate change would result in significant increases in the heat index in summer, and where relatively little space cooling has been needed in the past, but demands are likely to increase in the future. The increase in electricity demand is likely to be accelerated by population movements to the South and Southwest, which are regions of especially high per capita electricity use, due to demands for cooling in commercial buildings and households";


 * "Because nearly half of the nation’s electricity is currently generated from coal, these factors have the potential to increase total national carbon dioxide emissions in the absence of improved energy efficiency, development of non-carbon energy sources, and/or carbon capture and storage";


 * "Other effects of climate change on energy consumption are less clear, because little research has been done. For instance, in addition to cooling, air conditioners also remove moisture from the air; thus the increase in humidity projected to accompany global warming is likely to increase electricity consumption by air conditioners even further";


 * "In some regions, reductions in water supply due to decreases in precipitation and/or water from melting snowpack are likely to be significant, increasing the competition for water among various sectors including energy production";


 * "The production of energy from fossil fuels (coal, oil, and natural gas) is inextricably linked to the availability of adequate and sustainable supplies of water. While providing the United States with the majority of its annual energy needs, fossil fuels also place a high demand on the nation’s water resources in terms of both quantity and quality impacts. Generation of electricity in thermal power plants (coal, nuclear, gas, or oil) is water intensive. Power plants rank only slightly behind irrigation in terms of freshwater withdrawals in the United States";


 * "There is a high likelihood that water shortages will limit power plant electricity production in many regions. Future water constraints on electricity production in thermal power plants are projected for Arizona, Utah, Texas, Louisiana, Georgia, Alabama, Florida, California, Oregon, and Washington state by 2025. Additional parts of the United States could face similar constraints as a result of drought, growing populations, and increasing demand for water for various uses, at least seasonally. Situations where the development of new power plants is being slowed down or halted due to inadequate cooling water are becoming more frequent throughout the nation";


 * "In addition to the problem of water availability, there are issues related to an increase in water temperature. Use of warmer water reduces the efficiency of thermal power plant cooling technologies. And, warmer water discharged from power plants can alter species composition in aquatic ecosystems. Large coal and nuclear plants have been limited in their operations by reduced river levels caused by higher temperatures and thermal limits on water discharge";


 * "The efficiency of thermal power plants, fossil or nuclear, is sensitive to ambient air and water temperatures; higher temperatures reduce power outputs by affecting the efficiency of cooling. Although this effect is not large in percentage terms, even a relatively small change could have significant implications for total national electric power supply. For example, an average reduction of 1 percent in electricity generated by thermal power plants nationwide would mean a loss of 25 billion kilowatt-hours per year, about the amount of electricity consumed by 2 million Americans, a loss that would need to be supplied in some other way or offset through measures that improve energy efficiency";


 * "A significant fraction of America’s energy infrastructure is located near the coasts, from power plants, to oil refineries, to facilities that receive oil and gas deliveries. Rising sea levels are likely to lead to direct losses, such as equipment damage from flooding or erosion, and indirect effects, such as the costs of raising vulnerable assets to higher levels or building new facilities farther inland, increasing transportation costs. The U.S. East Coast and Gulf Coast have been identified as particularly vulnerable to sea-level rise because the land is relatively flat and also sinking in many places";


 * "The impacts of an increase in severe weather are not limited to hurricane-prone areas. For example, rail transportation lines, which carry approximately two-thirds of the coal to the nation’s power plants, often follow riverbeds, especially in the Appalachian region. More intense rainstorms, which have been observed and projected, can lead to rivers flooding, which can “wash out” or degrade nearby railbeds and roadbeds. This is also a problem in the Midwest, which experienced major flooding of the Mississippi River in 1993 and 2008".


 * "It is not yet possible to project effects of climate change on the grid, because so many of the effects would be more localized than current climate change models can depict; but, weather-related grid disturbances are recognized as a challenge for strategic planning and risk management;" and


 * Hydropower "is likely to be significantly affected by climate change in regions subject to reduced precipitation and/or water from melting snowpack. Significant changes are already being detected in the timing and amount of streamflows in many western rivers, consistent with the predicted effects of global warming. More precipitation coming as rain rather than snow, reduced snowpack, earlier peak runoff, and related effects are beginning to affect hydropower availability. Hydroelectric generation is very sensitive to changes in precipitation and river discharge. For example, every 1 percent decrease in precipitation results in a 2 to 3 percent drop in streamflow; every 1 percent decrease in streamflow in the Colorado River Basin results in a 3 percent drop in power generation. Such magnifying sensitivities occur because water flows through multiple power plants in a river basin".

Related SourceWatch articles

 * Global warming
 * Global Climate Change Impacts in the United States
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