SAN FRANCISCO United
States (Xinhua) -- A team from
University of California, Berkeley, and Lawrence Berkeley
National Laboratory has used resource mapping tools and assessed
the potential for large solar and wind farms in 21 countries in
southern and eastern Africa, concluding that renewable energy
has robust future in much of Africa.
studied, from Libya and Egypt in the north and along the eastern
coast to South Africa, include more than half of Africa’s
"The surprising find is that the wind and solar resources in
Africa are absolutely gigantic, and something you could tap into
for relatively low cost," said senior author Duncan Callaway, a
UC Berkeley associate professor of energy and resources and a
faculty scientist at Berkeley Lab.
Duncan Callaway added that "but we need to be thinking now
about strategies for fostering international collaboration to
tap into the resource in a way that is going to maximize its
potential while minimizing its impact."
With solar and wind farms, and international sharing of
power, most African nations could lower the number of
conventional power plants—fossil fuel and hydroelectric—they
need to build, thereby reducing their infrastructure costs by
perhaps billions of dollars.
The team set out to understand where wind and solar
generation plants might be built in the future under a range of
siting strategy scenarios, and how much renewable generators
might offset the need to build other forms of generation.
Based on the team’s analysis, choosing wind sites to match
the timing of wind generation with electricity demand is less
costly overall than choosing sites with the greatest wind energy
Assuming adequate transmission lines, strategies that take
into account the timing of wind generation result in a more even
distribution of wind capacity across countries than those that
maximize energy production.
The researchers say both energy trade and siting to match
generation with demand reduces the system costs of developing
wind sites that are low impact, that is, closer to existing
transmission lines, closer to areas where electricity would be
consumed and in areas with preexisting human activity as opposed
to pristine areas.
"Together, international energy trade and strategic siting
can enable African countries to pursue ‘no-regrets’ wind and
solar potential that can compete with conventional generation
technologies like coal and hydropower," said UC Berkeley
graduate student Grace Wu, who conducted the study with fellow
graduate student Ranjit Deshmukh.
Wu and Deshmukh, the lead authors of a study published online
in the journal Proceedings of the National Academy of Sciences,
gathered previously unavailable information on the annual solar
and wind resources in 21 countries in eastern and southern
Africa, and hourly estimates of wind speeds for nine countries
south of the Sahara Desert, and developed an energy resource
mapping framework, which they call Multi-criteria Analysis for
Planning Renewable Energy, or MapRE, to identify and
characterize potential wind and solar projects.
They then modeled various scenarios for siting wind power and
examined additional system costs from hydro and fossil fuels.
The team concluded that even after excluding solar and wind
farms from areas that are too remote or too close to sensitive
environmental or cultural sites, or what they term "no-regret"
sites, there is more than enough land in this part of Africa to
produce renewable power to meet the rising demand, if fossil
fuel and/or hydroelectric power are in the mix to even out the
Nevertheless, choosing only the most productive sites for
development, namely the windiest and sunniest, would leave some
countries with little low-cost local renewable energy
If, however, countries can agree to share power and build the
transmission lines to make that happen, all countries could
develop sites that are low-cost and accessible, and have low
environmental impact, while reducing the number of new hydro or
fossil fuel plants that need to be built.
"If you take the strategy of siting all of these systems such
that their total production correlates well with electricity
demand, then you save hundreds of millions to billions of
dollars per year versus the cost of electricity infrastructure
dominated by coal-fired plants or hydro," Callaway was quoted as
saying in a news release. "You also get a more equitable
distribution of generation sources across these countries."