New Data Confirms Big Hydro's Relative Decline

Patrick McCully

My recent blog comparing the global hydro industry’s stagnation with the rapid growth in the wind and solar sectors was based on preliminary data for wind and solar in 2009, and my guesstimate for that year’s hydro additions. Better statistics are now available for all three technologies.

In my blog I stated that the wind industry had likely installed at least a quarter more generating capacity than big hydro in 2009. The new stats, from the “Renewable Energy Policy Network for the 21st Century,” or REN21, shows that large hydro lagged even further behind than I had guesstimated.

The 38 gigawatts (GW) of wind turbines commissioned in 2009 is 36% greater than the 28 GW of large hydro. While wind installations surged by nearly a third in 2009, the REN21 numbers indicate that big hydro grew by less than two percent (half a GW) from the previous year. I can now be even more certain in the claim I made in my previous blog that “the dammers will never again get close to wind power's annual additions.”

However the small print of the REN21 report shows that big hydro additions in reality probably fell in 2009. REN21 changed how they define the small/large hydro split this year. The small hydro industry generally uses a 10 MW upper limit, but some countries have much higher limits - 25 MW in India, 30 MW in Brazil and the US, and a not-very-small-at-all 50 MW in China. In the past REN21 used the national standards, but this year they have made their statistics more consistent by switching to the 10 MW cut-off.

This changed definition has resulted in an apparent collapse in small hydro installations, from 7 GW in 2008 to just 3 GW in 2009. Because small hydro is benefiting from many of the same renewable support policies as wind and solar, it  is unlikely that there has in reality been any significant drop in small hydro installations as defined by governments. And it is therefore likely that had REN21 used their current methodology in 2008 they would have shown small hydro at similar levels to 2009. Taking 2008 small hydro installations as 3 GW and shifting 4 GW from the “small” to the “large” column would give 2008 large hydro additions as 31.5 GW. This means that 2009 may well have seen a 13% drop in big hydro additions.

Among the other pieces of good news in the REN21 report are:

  • “The geography of renewable energy is changing in ways that suggest a new era of geographic diversity. For example, wind power existed in just a handful of countries in the 1990s but now exists in over 82 countries.”

  • “Grid-connected solar PV has grown by an average of 60 percent every year for the past decade, increasing 100-fold since 2000.”

  • “Concentrating solar thermal power (CSP) emerged as a significant new power source during 2006–2010 . . . By early 2010, 0.7 GW of CSP was in operation, all in the U.S. Southwest and Spain, with construction or planning under way for much more capacity in many more countries.

  • “For the second year in a row, in both the United States and Europe, more renewable power capacity was added than conventional power capacity (coal, gas, nuclear). Renewables accounted for 60 percent of newly installed power capacity in Europe in 2009.”

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