[Sustain] Hydro Power (Especially New Dams) Emits Greenhouse Gasses!

[Eric Brooks]

Hi all,

Yet more proof that large hydro is not the answer.

See this section of 
http://www.crest.org/repp_pubs/articles/envImp/03climatechange.htm

"A potentially important aspect of the methane problem, about which 
little certain information exists, concerns large hydropower facilities. 
The World Commission on Dams (WCD), set up by the World Bank and the 
World Conservation Union (IUCN) to assess the role of dams in energy and 
water development, notes that oxygen-poor hydropower reservoirs can vent 
substantial quantities of methane, especially early in their lifetime, 
due to rotting vegetation beneath the waterline. ^*57 
<javascript:openWindow('00notes.htm#57', 'Notes', '375', '425')>* 
(Well-oxygenated reservoirs emit CO2 rather than methane.) For this 
reason, large, shallow hydropower reservoirs that inundate large 
quantities of biomass may not be justifiable on the basis of 
contributions to the mitigation of climate change.

For example, the Petit-Saut hydroelectric dam in French Guiana, which 
supplies power to the launch site of Europe's Ariane rocket program, 
submerged 365 square kilometers of tropical forest. One study reckons 
that during its first 20 years Petit-Saut will emit the equivalent of 66 
million metric tons of CO2 - about 85% from methane and the remainder 
from CO2 itself - making French Guiana one of the world's largest 
per-capita emitters of greenhouse gases. ^*58 
<javascript:openWindow('00notes.htm#58', 'Notes', '375', '425')>* While 
nontropical and more mature hydro-electric systems (including most U. S. 
facilities) have much lower emission rates, it is clear that tropical 
hydropower does not necessarily provide climatesafe energy, and may 
represent an important and poorly understood part of the climate 
problem.^*59 <javascript:openWindow('00notes.htm#59', 'Notes', '375', 
'425')> "*

-- 
"The past is the Textbook of Tyrants; the Future the Bible of the Free" - Herman Melville

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