As the Worldwatch Institute’s latest report shows, industrialised and developing countries continue to rely on hydro as a renewable electricity source.

The global use of hydropower increased by more than 5% between 2009-10, according to new research published by the Worldwatch Institute for its Vital Signs Online publication in January 2011. Hydropower use reached a record 3427TWh, or about 16.1% of global electricity consumption by the end of 2010, continuing the rapid rate of increase experienced between 2003 and 2009.

The cost of hydropower is relatively low, making it a competitive source of renewable electricity, with the average cost from a hydro plant larger than 10MW being three to five US cents per kilowatt-hour.

“In the future, hydropower is likely to continue to grow because of its competitive price and climate benefits, which make it an attractive option as countries seek to lower their greenhouse gas emissions,” said report author Matt Lucky, a Worldwatch MAP Sustainable Energy Fellow.

China was the largest hydropower producer and is expected to continue to lead global hydro use in the coming years. The country produced 721TWh in 2010, representing around 17% of domestic electricity use. China also had the highest installed hydropower capacity, with 213GW at the end of 2010. It added more hydro capacity than any other country, 16GW in 2010, and plans to add 140GW by 2015. This is equivalent to building about seven more dams the size of China’s Three Gorges dam, currently the largest in the world.

Although hydropower is produced in at least 150 countries it is concentrated in just a few countries and regions. The Asia-Pacific region generated roughly 32% of global hydropower in 2010.

Europe and Eurasia, South and Central America, and North America are the next highest producing regions of the world, at 25.3%, 20.3% and 19.3% respectively. Although Africa trails behind at 3% (just ahead of the Middle East’s 0.4%) it is still considered the region with the greatest potential for increased production.

China, Brazil, the US, Canada, and Russia accounted for approximately 52% of installed hydropower capacity worldwide at the end of 2010. Brazil at 80.7GW was followed by the US (78GW), Canada (75.6GW), and Russia (55GW). The EU-27 countries also had 130GW of installed hydropower by the end of 2010.

Brazil added 5GW of hydropower capacity to the grid in 2010, and there were an additional 8.9GW of hydropower under construction at the time. Canada added 0.5GW in 2010, and an additional 11GW were also under construction at the time. In total US$40-45B was invested in large hydropower projects worldwide in 2010.

There are now three hydropower plants larger than 10GW around the world. The largest is the Three Gorges dam in China and rated at 18.2GW; it is expected the power plant will be upgraded to 22.5GW by 2012. The next largest power plants are Brazil’s Itaipu rated at 14GW, and the Guri dam in Venezuela rated at 10.2GW. Brazil is also home to the world’s fourth largest hydropower plant, the 8.5GW Tucuruí dam.

In 2008, four countries (Albania, Bhutan, Lesotho, and Paraguay generated all their electricity from hydropower. They were included in a list of 15 countries which generated at least 90% of their electricity from hydro. Iceland, New Zealand, and Norway producing the most hydropower per capita.

In 2010, pumped storage hydropower grew by 4GW and an additional 5GW were also under construction. There are 136GW of operating pumped storage hydropower worldwide with Europe, Japan and the US having most of this capacity.

Micro hydropower (with an installed capacity of 100kWh or less) has grown in importance over the last decade and can be an effective means of providing electricity to communities far from industrial centres. As of 2009, roughly 60GW of small hydro (less than 10 MW) was installed worldwide, accounting for less than 6% of the hydropower total. Fifty-five percent, or 33GW, of this capacity was located in China. Japan (4GW), the US (3GW), Germany (2GW), India (2GW) and Spain (2GW) were the countries with the next greatest amount of installed small hydropower as of 2009. Around US$2B was invested in small hydropower projects worldwide in 2010, down 43 percent from 2009. However, small hydro is likely to expand, especially as populous countries like India continue to pursue rural electrification.

Hydropower will likely continue to grow in the future. Its competitive price and climate benefits will make it an attractive option as countries attempt to lower their greenhouse gas emissions. Very large hydropower projects in China and Brazil are likely to make up a majority of this growth but the role of small hydropower is also well-suited to expansion.

Matt Lucky is a MAP Sustainable Energy Fellow at the Worldwatch Institute for 2010–11. Worldwatch is an independent research organisation based in Washington, DC that works on energy, resource and environmental issues. The Institute’s State of the World report is published annually in more than 20 languages. For more information, visit www.worldwatch.org.