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Our U.S. energy policy is at a crossroads. Where we get our energy and how we use it is at the forefront of an important national discussion, with the outcome to shape the future of our country, its citizens and our children. The debate is keenly focused on how to meet consumer and business demand for energy, while also reducing the nation’s dependence on foreign sources and mitigating the potentially harmful effects of traditional energy sources on the environment.
This issue has become increasingly complex as the government seeks to revive the economy amid one of the deepest recessions in U.S. history. Some priorities have already been outlined to address the most pressing energy issues, including updating the nation’s power transmission system, encouraging energy efficiency practices among consumers and businesses, developing new energy technology and spurring development of clean coal technologies and additional renewable energy sources. Besides strengthening the nation’s energy portfolio, all of these efforts have the potential to jump-start the economy and create thousands of so-called “green-collar” American jobs.
States also are beginning to address energy challenges by encouraging development of renewable energy sources. Some have required energy companies to derive specific percentages of energy from defined renewable sources. Recognizing the vast renewable resources in their backyards, Western states have become particularly active on this front. Colorado, for instance, was the first U.S. state to pass such a requirement and now requires that utilities generate at least 20 percent of their electricity from renewable sources.
While wind and solar power has largely dominated the renewable energy discussion in recent years, hydropower has staged a quiet comeback. Currently, hydropower ranks among the largest sources of renewable energy in the world, accounting for 63 percent of the energy produced from renewable sources, according to REN21, an international policy group based in Paris. All told, hydropower accounts for about 19 percent of the world’s electricity, or 715,000 MW, up from 16 percent in 2003. In the U.S., hydropower provides about10 percent of our electricity today, with a much higher percentage in certain regions, such as the Pacific Northwest.
With that in mind, power producers and utilities are pursuing a variety of strategies to increase the amount of energy being derived from hydroelectric sources. But instead of building new dams, which often are opposed by environmental groups, savvy engineers are retrofitting existing dams to add hydroelectric capacity at sites that currently lack it. Just 3 percent of the nation’s 80,000 dams currently have hydroelectric capacity, prompting numerous organizations to conduct feasibility studies to gauge the viability of adding hydro at locks and dams across the U.S.
Improving the way water is stored, delivered and used can result in higher power production at existing hydropower facilities. This can be done through equipment improvements, better reservoir regulation, small increases in reservoir water levels or other hydraulic improvements. Adding additional hydropower units at existing facilities may also allow for increased renewable generation. Replacing old and out-of-date equipment with modern equipment can result in increased power production. As municipalities and utilities examine their strategic alternatives for power generation and seek to adhere to state renewable portfolio requirements, dams and reservoirs represent a vast pool of potential energy.
Another emerging trend also could provide a boost for hydropower and employment in the renewable sector. If the U.S. enacts a carbon cap-and-trade system similar to Europe, hydro producers may find a lucrative market in creating and selling carbon credits. In 2007, the Chelan County Public Utilities District in Washington State became the first hydroelectric power producer to provide carbon dioxide offsets for the Chicago Climate Exchange, the nation’s largest exchange for greenhouse gas credits. Chelan PUD was able to sell the credits after it increased the efficiency and lessened the environmental impacts of three powerhouses along the Columbia River. The move sets a precedent for other hydropower producers to be recognized as alternative energy providers in the U.S., paving the way for the sale of additional hydro-related credits.
Hydropower can also work in tandem with renewable energy sources, including wind and solar. For instance, pumped-storage hydroelectric facilities are designed to store large quantities of water that can then be tapped “on demand” to generate significant streams of power. This stored energy can supplement other renewable energy sources that are dependent on external factors, such as the wind blowing or the sun shining. Combining hydropower with other sources of renewable energy also would help stabilize the nation’s transmission grid and pave the way for the so-called “smart grid,” which seeks to use digital technology to better use our existing generated electricity and reduce wasted energy usage and energy costs.
No single form of energy can stand alone to meet the growing U.S. energy needs. By 2025, U.S. energy demand is expected to increase 35 percent, according to the Energy Information Administration’s “Annual Energy Outlook.” Renewable energy, including hydropower, will play a pivotal role in addressing the nation’s future energy and employment needs, while also reducing America’s carbon footprint. Updating and expanding the nation’s energy portfolio to include an array of renewable sources will improve our energy infrastructure and create thousands of green jobs. Doing this will create a win-win-win situation for private industry, the government and the environment.
Author: Norman A. Bishop is a vice president of MWH Americas Inc. and is its Hydro and Dams Market Sector Leader.
Power Engineering July, 2009
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