Until 1948, Hoover Dam was the largest hydroelectric plant in the world. It’s still the most visited dam in the world, with over 7 million tourists touring it each year credit: Airwolfhound
Hydroelectricity is often overlooked in discussions of renewable energy sources, despite being the world’s largest source of non-fossil-fuel power. But that may be changing.
According to the British Petroleum’s 2014 Statistical Review of World Energy, global usage of hydroelectricity has been increasing over the last decade. China tops the list of countries that have invested in new hydropower, with an almost five percent increase from 2012 to 2013.
The benefits are obvious: The cost of hydroelectricity is fairly low, just three to five U.S. cents per kilowatt-hour, compared to around 13 cents per kilowatt hour for conventionally-produced electricity. Hydroelectric plants also emit far less carbon dioxide than their fossil fuel counterparts.
Once a plant is constructed, it will produce no direct waste. Hydroelectricity is an easily scaled resource -- the amount of energy produced can quickly be increased to match a spike in demand. It’s also obviously green – the only pollution involved is when a plant is being constructed. Finally, it’s reliable; as long as there’s water in the reservoir, energy can be produced.
Hydropower is not perfect, however. As with most forms of energy production, there are negatives. Dams change the flow of the water and can impact fish populations – sometimes negatively, but sometimes positively, too, as unregulated rivers can have large and unexpected fluctuations in flow. (This excellent interactive animated graphic lets you experience how a water system works in its natural state, with a poorly run dam, and with a well-run dam.)
Another potential problem is drought. Hydropower plants are dependent on how much water is available. California’s hydroelectric portfolio is in danger due to the current drought; as of February, most of the state’s reservoirs were well below 50 percent of their capacity.
Despite those challenges, some 150 countries partially rely on hydroelectricity for clean, predictable energy. Use by Asian-Pacific countries is up 36 percent from 2012 levels and the U.S. and Canada increased their reliance on hydropower by seven percent and 10 percent, respectively. In Pakistan, hydropower is leading the way as a cheaper alternative to fossil fuel-based energy.
Technological advancements are fueling hydropower’s growth. In 2012, Verdant Power installed a three-bladed electric turbine into New York’s East River. As many as 30 turbines could ultimately dot the waterway by 2017.
There’s also been progress in addressing some of the environmental concerns posed by dams. For fresh-water fish like trout that need to travel upstream, dams present a life-altering impediment. Some hydroelectric plants, like Montana’s Thompson Falls plant, have implemented “fish ladders” that allow native species to continue their natural ascent up the river.
It’s the kind innovation that can only encourage a wider adoption of hydropower.
By. Amy Gleich of Oilprice.com