A Makeover for Hoover Dam
Hydropower has attracted increasing attention in recent years as a renewable type of clean energy. As long as a suitable water source is available, hydropower facilities are usually good investments, producing energy in a manner that generates far less air pollution and CO2 emissions than fossil fuels do. The most common way to generate hydropower is to trap water at a high elevation behind a dam so it can be released and used to spin turbines below, which, in turn, power electricity-producing generators. However, hydropower has its drawbacks. Droughts and increased water consumption have reduced the flow of many rivers. As rivers become shallower, the necessary volume of water for electricity generation is more difficult to maintain, and power supply and dependability are negatively impacted.
Variability in water levels has particularly affected Hoover Dam, a mega-scale hydropower facility in the US state of Nevada. Built in the 1930s at enormous expense to control the frequently flooding Colorado River and maintain a water supply for farmland irrigation, the dam’s hydropower capabilities were seen as a way to recover some of the costs of its construction over the long term. The dam’s electricity-generating capacity, however, was challenged from the start by seasonal variability in water flow, and in recent years has been greatly reduced by droughts.
Combining hydropower with other alternative energy sources, though, may offer a solution. Solar and wind plants can produce enormous amounts of electricity, but one serious downside is that the energy they produce is not available when there is little sun or wind. While conventional batteries can help with this issue, storing such tremendous volumes of electricity has long been a challenge. A recently proposed system for Hoover Dam could provide an answer, though. The plan suggests building a new pumping station that would be powered by both wind and solar. It would push water from the river back up to Hoover Dam, refilling the lake behind it. The water could be released anytime to power the dam’s generators in order to reliably meet demand for electricity. Kelly Sanders, an engineering professor at the University of Southern California, is enthusiastic about the storage plan, saying, “We don’t have anything on the horizon as far as batteries of that magnitude.”
Of course, any project as ambitious as this, with its $3 billion price tag for a pipeline and pump station powered by solar and wind energy, is likely to attract objections. Communities downstream from Hoover Dam fear a further reduction in water levels in the Colorado River could endanger jobs in tourism and recreation, and environmental activists have expressed concern that wildlife populations and wetlands could also be impacted by the project. With the urgent need to secure energy sources that can replace fossil fuels, however, the pressure to use hydropower to supplement solar and wind power sources seems sure to intensify. While the project is still in the planning stages, and various governmental approvals are still required, if everything goes as scheduled, the alterations to the dam could be completed by 2028.
