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Renewable Energy Not Always Sustainable |
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By Gustavo González*
Latin
America obtains more than 20 percent of its energy from ostensibly
renewable sources. But much of it comes from hydroelectric dams,
which can harm ecosystems.
SANTIAGO - The proportion of 10 percent renewable
sources for supplying energy, set as a global goal for 2010, is
already a reality in Latin America, but that has been achieved mostly
through big hydroelectric dams, which environmentalists argue are
not sustainable.
When the region assumed that goal in 2002, it used nearly 26 percent
renewable sources, but 15 percent was hydroelectric, according to
figures from the Economic Commission for Latin America and the Caribbean
(ECLAC), a regional agency of the United Nations.
Renewable does not mean sustainable, say activists and experts who
want to see fewer gigantic dams and more regulation of the use of
firewood (source of 5.8 percent of energy used in the region in
2002), and incentives for non-conventional sources.
They point to Costa Rica, where 50 percent of the energy matrix
is supplied by geothermal energy, sugarcane waste, biomass and other
renewable sources.
International Conference for Renewable Energies, held in Bonn, Jun.
1-4, drew delegates from 154 countries who assessed progress towards
the goal of replacing fossil fuels in the global energy matrix that
was set in 2002 at the World Summit on Sustainable Development in
Johannesburg.
The goal of 10 percent renewable energy by 2010 represents ''the
opportunity to fight poverty by using local natural resources in
a decentralized way, the possibility of overcoming dependence on
fossil fuels, which now represent significant costs for the nations
of the South, and the urgency of protecting the climate and the
environment,'' Sara Larraín, director of Sustainable Chile, told
Tierramérica.
Around 23 percent of Latin America's total primary energy supply
(TPES) comes from renewable sources, including hydroelectric dams,
according to the ECLAC study ''Energy sustainability in Latin America
and the Caribbean: the share of renewable sources'', published in
October 2003.
The report says that Argentina, highly dependent on natural gas,
is the only country in the region with under 10 percent renewable
energy sources, but there are four others in the critical zone of
10 to 20 percent: Mexico, Ecuador, Venezuela and Chile.
On the other extreme are Costa Rica, with 99.2 percent renewable
energy, followed by Paraguay, Honduras, Haiti and El Salvador, with
more than 80 percent.
But in that group all is not positive. Paraguay is almost totally
dependent on hydroelectric energy, while Honduras, Haiti and El
Salvador, like its Central American neighbors Nicaragua and Guatemala,
rely heavily on ''dendroenergy'': firewood.
Activists and experts argue that big hydroelectric dams hurt the
ecosystems around them and alter the living conditions of local
communities, which are generally indigenous groups.
Firewood is a renewable resource as long as it is accompanied by
adequate reforestation.
Manlio Coviello and Hugo Altomonte, authors of the ECLAC study,
argue that reliance on firewood is ''disturbing and to a certain
extent negative, because of the heavy impact it has on forestry
resources and the consequent increase in carbon dioxide emissions
from burning wood.''
Carbon dioxide emissions are the main cause of what is known as
the greenhouse effect.
The most accessible renewable source currently seems to be geothermal
energy, given the high costs still associated with widespread use
of solar, wind or wave power, though biomass (made from biological
waste) is also gaining ground, as are small hydroelectric dams,
which are also seen as more sustainable.
''Brazil has the most sustainable and cleanest energy matrix in
the world,'' with 90 percent of its TPES based on renewable sources,
including hydroelectric power, Emilio La Rovere, professor of energy
planning at the University of Rio de Janeiro, told Tierramérica.
In the wake of the 1970s energy crisis, Brazil developed sugarcane
alcohol as a gasoline substitute.
In recent years, automotive companies have developed engines that
use gasoline or alcohol, or the two mixed, and are working on ''trivalent''
models that could also run on natural gas. Today in Brazil there
are 700,000 to 800,000 natural gas-run vehicles, a figure that only
Argentina surpasses.
One case that environmentalists point to is Cuba. The Caribbean
island's energy matrix ''is sustainable because it is changeable
and is tending towards achieving sustainable energy development,''
Luis Bérriz, president of the non-governmental group Cubasolar,
told Tierramérica.
Cuba relied heavily on Soviet petroleum until the early 1990s. The
collapse of the Soviet Union led to an interruption in supplies
and pushed Cuba into crisis. Since then, Havana has been developing
its own hydrocarbon resources, energy conservation plans, and pursuing
research of renewable energy sources.
But the ECLAC report finds that Cuba still depends on petroleum,
which represents 56.1 percent of its TPES, while renewable sources
comprise 37.9 percent, and are mostly sugarcane byproducts (34.5
percent), which tend to use ''combustion processes that are not
very efficient.''
* Gustavo González is an IPS correspondent.
With reporting by Patricia Grogg in Cuba and Mario Osava in Brazil.
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