IEEE Spectrum May, 2015 - 42

Microhydroelectric systems like Rivera's run at full
capacity only when there's enough rain. At drier times,
they generate less power or none at all. But the bigger,
newer sites need to operate continuously and sell their
excess power to the grid to recoup their up-front cost,
says Leaf. The cost of raw materials like copper has
soared, and the increasing automation of the plants'
control systems, which rely on more expensive components and software, has also driven up costs.
Ensuring a steady supply of water for its hydropower
plants has been a challenge for ATDER‑BL, and it has
pushed its engineers into an unexpected new sideline:
watershed conservation. In this regard, the association's biggest project to date, located at the foot of a
EspITE ITs INTERNATIoNAL reputation, ATDER‑BL
steep rocky stream near the tiny town of El Bote, prehas never lost its local focus. Just as the group had
sented a thorny challenge.
done in El Cuá and Bocay, it still leans heavily on
The 930-kW plant, completed in 2008 and financed
local workers for the construction of each new
in part with a US $1.3 million loan from the World Bank
hydroelectric plant, explains electrical engineer
and $400,000 from the nonprofit Green Empowerment,
Abner Talen. The association asks each household to provide a
based in Portland, Ore., now generates about 5.8 gigawattvolunteer to do the less technical work: branch clearing, pole hoisthours per year, enough to power around 6,000 homes in
ing, cable laying, concrete pouring. ATDER‑BL's crew does the rest.
the region. And the local community is thriving. "El Bote
"The people have to be willing to work," Talen says. "They have
is a town of only 95 houses," Leaf says, "but as soon as
to take on the project as their own." Countless other well-meaning
there was electricity available, they started increasing
development efforts don't follow that approach-and they fail, he
the years of schooling...and they graduated the first class
adds. "There are lots of experiences where the population was
of high school students about three years ago."
given everything and then they don't take care of it like they should."
But even as construction of the power plant got under
One of the smallest of ATDER‑BL's hydropower plants is a 2-kW sysway in 2002, the surrounding area was rapidly changtem owned and operated by a coffee grower named Martín Rivera
ing-for the worse. On Leaf's first visit to the Bosawás
and his neighbors. His house is nestled on a lush slope surrounded
Biosphere Reserve, northeast of El Bote, she recalls,
by bushes heavy with red, ripening coffee berries. Several years
"It looked like a place for a Tarzan movie, with vines
ago ATDER‑BL advised him and his neighbors when they installed
dangling down from the trees along the side of the river
their plant. Now the generator hums in a closet-size shed downand flocks of red parrots flying overhead, the monkeys
hill from Rivera's farm. Upstream, a tiny dam hidden in the thick
calling from the trees nearby, throwing things at you."
forest captures the water to drive the small Pelton wheel turbine.
But at the forest's edges, she says, "we saw the virgin
Twenty years ago, Rivera would have never worked with a
forest smoldering. It was the slash and
group like ATDER‑BL. He fought on the side of the contras, and
burn of poor people needing to estabduring the worst of the fighting, he sent his son
lish agriculture."
Álvaro to the lowlands to study. When the war pEopLE powER: workers
Such wholesale land clearing is bad
ended, Rivera returned to farming. And his son, from ATDER-BL and local
volunteers haul a 25-kilowatt
for hydroelectricity. Fields of corn and
who'd gotten an agricultural engineering degree, microturbine, which now
beans, which the poorest farmers plant
came home and began working for ATDER‑BL.
powers three small villages.
because they offer a quick return on investment, are prone to soil erosion. During the rainy season,
the sediment washes from deforested farmland, clogs
streams, disrupts dams, and hobbles the hydropower
generators. And without the shade of trees overhead,
streambeds dry up.
Someone had to ensure the region has enough water
to feed its hydropower plants, and that person turned
out to be Boanerge Rocha Moreno. The agricultural
engineer stands at the intersection of two dirt roads,
where one-room wooden houses sport rooftop satellite dishes. He wears a Boston Red Sox cap, a spotless
white polo shirt, jeans, and rubber boots.
powers about 4,000 homes. In total the group, which now has
a full-time staff of 40, has installed about 30 small hydroelectric
plants throughout the region. It has consulted for Nicaragua's
Ministry of Mines and Energy and the United Nations Development Programme on dozens more.
"ATDER‑BL's work has improved the quality of life for thousands
of Nicaraguans, from schoolchildren to farmers, with the support
and help of local communities," says Laurie Guevara-Stone of the
Rocky Mountain Institute, in Snowmass, Colo., who has worked
on renewable energy in Nicaragua and other Central American
countries. "Their approach could really serve as a model for rural
electrification in other parts of the world."

may 2015

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Table of Contents for the Digital Edition of IEEE Spectrum May, 2015