Growing water demand and reduced runoff due to drought has depleted waters feeding many hydroelectric power plants around the world—sometimes causing severe power shortages, such as in Brazil and New Zealand. The 2,080-MW Hoover Dam (Figure 4), a facility that generates power for more than a million people in Arizona, Nevada, and Southern California, is not immune to this phenomenon. According to a recent study by the Scripps Institution of Oceanography, the Colorado River system, which includes Lake Powell and Lake Mead (both manmade reservoirs), is suffering a net deficit of nearly one million acre-feet of water per year.
Mexico has already developed substantial large hydro and geothermal resources. However, without policy changes and government-sponsored financial incentives, unconventional renewable sources are taking the equivalent of baby steps.
Shrinking water supplies will unquestionably constrain the development of future power plants. A hybrid system consisting of concentrated solar thermal power and desalination to produce water for a plant, integrated with a combined cycle or conventional steam plant, may be the simple solution.
In mid-February, the Geological Society of London raised the hopes of those promoting geothermal energy when results of exploratory drilling in Weardale, County Durham, revealed record levels of permeability in granite. Although the results are promising for the development of geothermal energy, they may have less welcome implications for the safe disposal of radioactive waste in deep repositories.
In late January, a 1.5-MW concentrating solar power (CSP) plant began providing power to Salt River Project customers in Greater Phoenix, Ariz. Though small, the plant, developed by Tessera Solar and Stirling Energy Systems (SES), is seen as a prelude to 1,500-MW projects that are due to break ground in California and Texas later this year.
Greensburg was destroyed by an EF5 tornado on May 4, 2007. Instead of abandoning the Kansas town, the community quickly embraced the task of rebuilding it from the ground up, maximizing the use of renewable energy sources and energy efficient building techniques. Rebuilding continues, but the future of Greensburg has never been stronger.
Ocean Power Technologies Inc. (OPT) announced on Feb. 1 that it had successfully deployed one of its PowerBuoy wave energy devices about a mile offshore from a U.S. Marine Corps Base on the island of Oahu in Hawaii. The device generates up to 40 kW of power from the rise and fall of waves, and since its deployment in December 2009, it has been generating power within specifications.
In response to Ontario’s provincial regulatory mandates to phase out the use of coal by the end of 2014, Ontario Power Generation (OPG) is exploring its capability to employ biomass feedstocks to displace coal in some units within the OPG thermal fleet. The primary fuels employed during the respective trials at its Nanticoke and Atikokan Generating Stations have been agricultural by-products and commercial grade wood pellets. The Canadian utility has learned valuable lessons about fuel supply and logistics, and the technical challenges of safely handling and firing high levels of biomass.
Ethiopia in mid-January officially inaugurated the 420-MW Gilgel Gibe II hydropower project, the second hydropower plant to be opened since November 2009, when the 300-MW Tekezé project began operations.
Water and gas provide the energy for Peru’s power generation sector, and the country could generate considerably more, especially from hydro and wind. While the nation strives to extend electricity service to all its citizens, it’s also looking beyond its borders for potential future customers.