The doomed Hydropower

Being very concern about the climate change, our group chose the last topic for our roundtable discussion. And after discussion, we came out with a conclusion that R&D in new powers, or in modification of the thermal power generation method, which is currently widely adopted, are a possible way to mitigate climate change.

Being too optimistic on the promising hydropower generation, I did a research on disadvantages of the hydropower generation method. After a brief online research, I would like to summarize two relevant articles concerning the pros and cons of hydropower.

The first sentence in Duncan Graham-Rowe’s “Hydroelectric power's dirty secret revealed” shocked me: “Contrary to popular belief, hydroelectric power can seriously damage the climate.” Even Eric Dunchemin, a consultant for the IPCC, agrees with this point of view. According to Philip Fearnside from Brazil's National Institute for Research in the Amazon in Manaus, Hydropower dams produce even more methane and carbon dioxide than normal thermal power stations. And examples are given to support this idea, the greenhouse effects tripled after a dam was built in Para, Brazil. The reason for this unexpected result was due to the flooding of green plants at the stage to form the reservoir, the green plants died and thus the capacity of this region’s ability to convert carbon dioxide to oxygen through photosynthesis process is decreased, leading to the higher greenhouse effects. Furthermore, the dead bodies of the green plants decayed underwater with absence of oxygen to form huge amount of methane trapped underwater. Thus once the methane is released, the greenhouse effects will be further worsened. And to make things even worse, methane's effect on global warming is 21 times stronger than carbon dioxide's.

Being apparently disappointed and disheartened after reading this pessimistic article, I would like to summarize another article from an energy analysis website. This article, “Micro Hydro Power - Pros and Cons” discussed the advantages and disadvantages of micro hydro powers, which is to use water flow energy from streams instead of big rivers like the Yangtze River where china’s Three Gorge’s Hydropower Station lies on. And this method definitely solved the problem outlined in the previous article. And to build a small-scale hydro-power system can cost from $1,000 - $20,000 only, and maintenance fee will also be relatively low. Developing countries can adopt this technology faster and easier as it requires less capital to put in compared to large projects, say a nuclear power station. However nothing is perfect. Micro hydropower has remarkably numerous of disadvantages as well. The most visible one is it can only be built based on small scales, thus it does not fulfill the large energy demand in most industrialized countries. As the same time, though the micro hydropower plants are built at smaller scale, the impact on diverting the streams is still the same, and it is not negligible. And unlike big rivers for example, the Mississippi’s, streams might dry up during dry seasons.

After this brief online research, hydropower, being the well-commented new way to acquire energy, has numerous disadvantages of itself, and these disadvantages cannot be easily solved because they are all from its way of functionality to convert hydropower into electricity.

However, hydropower is not to be denied as a possible new way to generate electricity. Compared to thermal power generation, it is still much more environmentally friendly. Scientists should not feel doomed because hydropower is not a very suitable way to solve our current crisis, instead, more R&D should be done to find better ways to generate electricity, for example, wind power or solar power maybe?




Vocab List: (is it because the articles are too easy…? I actually saw unknown vocab…)
Drawdown: The Drawdown is the measure of the decline from a historical peak in some variable.
Agenda: a temporally organized plan for matters to be attended to


Duncan Graham-Rowe(2005), Hydroelectric power's dirty secret revealed, retrieved on 2nd March 2009, from http://www.newscientist.com/article/dn7046.
Micro Hydro Power - Pros and Cons, (2006), retrieved on 2nd March 2009, from http://www.alternative-energy-news.info/micro-hydro-power-pros-and-cons.