Hydro

An Australian sewage plant this April began using treated wastewater falling down a 60-meter (m) shaft to produce its own power.

While Europe’s offshore wind sector has taken off, interest is resurging in marine energy. The UK’s Crown Estate took the major step this March, for example, of awarding leasing rights to 10 wave power projects to develop generation in Scotland’s Pentland Firth and Orkney waters of the North Sea.

It’s no surprise that China leads the world in recent power capacity additions. What may surprise you is the precise mix of options this vast country is relying upon to meet its ever-growing demand for electricity. As a result, this ancient civilization is fast becoming the test bed and factory for the newest generation and transmission technologies.

As U.S. utilities increase the percentage of renewable energy in their generation portfolio, they must deal with a number of key issues related to selecting specific technologies. Additionally, they must figure out what it will take to make renewables emerge as a mainstream generating option in the future.

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.

Soldiers could one day carry 600-W power plants on their backs, or set up arrays of up to 20 kW in streams deeper than 4 feet, if a prototype being developed by California-based Bourne Energy comes to fruition.

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.

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.

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.

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.