Friday, June 10, 2011

Hold the Hydro-Powered Wagon! the
Hydro-Powered Wagon!
April 29, 2011 By jlpowerg Leave a Comment
Article by Celeste Yates

World Wide Fund for Nature (WWF) reported that one-half of South
Africa�s electricity generation could come from renewable energy.
According to WWF Climate Change Programme Manager, Richard
Worthington, South African could feasible reach 50% renewable energy
target by 2030.

At the Hydropower Africa Conference in Johannesburg earlier this week
it was highlighted that hydropower could save Africa -billion a year
in terms of electricity generation and regional power trade. While
capital cost and infrastructure propose a current obstacle to
developing hydropower, departmental governments attending the
conference sat up and noticed.

Nelisiwe Magubane, director-general of South Africa�s Department of
Energy, said that the hydropower potential in Africa could not be
underestimated at this critical time in the continent�s development.
Meanwhile WWF has advocated the construction of Kusile, Eskom�s coal-
fired power station to be built after the Medupi power station, be
stopped. There has also been recent reports that there will be a
electricity supply shortfall which will emerge again during the course
of next year. Uganda is starting to look into developing small
hydropower plants, while Rwanda�s ministry of infrastructure head of
hydropower Emmanuel Kirenga announed at the conference that Rwanda is
planning to boost its hydropower generation. Zambia is constructing
its hydropower plant by 2011.

So it seems that in a time when our fellow Africans are rushing
forward in hydropower, South Africa is still dealing with last year�s
issues. Should we just rush forward as well? When thinking about the
environment, using rushing water to power a city does in theory sound
much better than using coal. There is no smoke, no soot or radioactive
waste. In fact a lot of people place hydropower into the same safe,
green category as wind power and solar power. But as with each of
these, there are biodiversity and environmental impacts.

The worst version, from a biodiversity perspective, is the
hydroelectric dams. These massive, concrete creation drown enormous
amounts of land behind them, but do create the most amount of
electricity. There are smaller versions of the hydroelectric dams,
which cause less environment disruption, but also create less

The first obvious disruption is the impact behind the dam. Other than
filling up previous ecosystems with water and drowning the valley,
there are the aquatic ecosystems to take into account, both upstream
and downstream. Downstream there will be erosion issues, water
temperature changes and oxygen levels to take into consideration due
to the water passing through the dam�s turbines.

Then there is the valley that has just been drowned. Depending on the
development of the dam, the ecosystem could be a wetland or even a
forest. Either way that ecosystem was holding a lot of carbon, which
will be released during the flooding and afterwards when the plants
and trees start to decompose. This doesn�t only release emissions from
a global perspective, but alters the water chemically. Plus you add
the concrete to build the dams and transportation to get the materials
to the site and the negative effects start really adding up.

It�s not only the position of the dam that needs to be taken into
consideration, but also were the water ends up. Wetlands and river
mouths will be influenced by the dam. Of course you could argue the
negative environmental impacts of coal-fuelled power plants, which are
more obviously visible than a pretty waterfall. The full impacts of
hydropower have still yet to be researched. While the concept is
supported by organisations such as WWF, in their statements they
always bring up the fact that serious considerations need to be taken
into account and proper research has to be done before even the first
wheelbarrow of cement is shipped out.

Locations are vitally important and in a country were water is already
scarce, it is even more so. The second thing to take into account is
the biodiversity, not only on the land, but in the freshwater. Already
over 20% of freshwater fish species have gone extinct globally. In
South Africa, almost 50% of freshwater ecosystems are critically

South Africa doesn�t have the best track record of looking before
walking. But hopefully we would have learnt from our neighbours in
Zambia, who after building dams in the 1970s, completely disrupted and
reduced water in the area and changed the timing of the flooding in
the Kafue Flats upstream. The negative effects not only included in
water resource availability and impacts on wildlife and fish, but also
reduced potential for tourism.

At this moment in time, hydropower in South Africa is still majority
only a theory. Although according to the White Paper in Renewable
Energy, South Africa areas in the Eastern Cape and KwaZulu-Natal
provinces show a lot of potential for the development of small
hydropower plants. Currently the white paper, published in 2003, has
the following target for 2013: �10 000 GWh (0.8 Mtoe) renewable energy
contribution to final energy consumption by 2013, to be produced
mainly from biomass, wind, solar and small-scale hydro. The renewable
energy is to be utilised for power generation and non-electric
technologies such as solar water heating and bio-fuels. This is
approximately 4% (1667 MW) of the estimated electricity demand (41539
MW) by 2013.�

Irrespective of the size of installation, any hydropower development
will require authorisation in terms of the National Water Act (DWAF,

About the Author

Celeste works for South African Biodiversity Media. To find more
articles, news and information about biodiversity and environmental
issues in South African, go to

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