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How do they work? The wind turbine, which is installed on top of a tall tower, collects
wind energy and converts it into electricity. The electricity is used to charge batteries,
reduce the fuel consumption on a diesel generator, or drive a pump. Since the wind is
intermittent, some sort of storage is usually incorporated into the system and back-up
generators are often used.
What applications are they used for? In developing countries small wind turbines are
primarily used for rural energy applications. Rural electrification of homes, villages,
farms, and small industries can often be done less expensively and more quickly with
renewable energy, such as wind power, than by extending the utility grid. Using newly
developed wind-electric pumping technology, wind turbine systems are also being used for
village water supply and irrigation. These new windpumps provide an alternative to the
traditional diesel powered pump.
Why are these systems any better than grid extension or diesels? They are better because
they are more sustainable and offer a number of other socioeconomic benefits. Wind systems
are smaller, modular and have a shorter leadtime than grid extension. For grid extension
distances as short as one kilometer a wind system can be a lower cost alternative for
small loads. While they cost more initially than diesels they are much better from the
users point of view. Donor agencies, for example, typically supply diesels at no cost, but
leave operational costs (fuel, maintenance and replacement) to the local people. This
requires scarce hard currency and usually results in limited utilization and a shortened
life of the diesel because of inadequate maintenance. Many countries must also import
their fossil fuels, further magnifying the burden imposed by diesels.
Can you give some concrete examples? In India the government is using 20 kW wind system
packages, using two of our 10 kW units, to bring electricity to villages far from the
utility grid. Jengging village, Arunachal Pradesh, which is in the foothills of the
Himalayan Mountains, for example, was electrified with wind turbines in 1988. Due to the
rugged terrain in the area it is doubtful that utility lines would ever be brought to
Jengging.
In Morocco the government, with the support of US-AID, is using wind-electric pumping
systems to replace diesel powered pumps that are too expensive for the local people to
operate. In the Naima Rural Commune, near Oujda in northeast Morocco, two 10 kW wind
turbines are supplying four villages with several times the water volume previously pumped
by diesels. The villagers prefer the wind turbines both because they deliver more water
and because they cost nothing to operate.
In fact, the largest decentralized rural electrification project in the world is based on
wind generators. In China, over 100,000 locally produced small wind turbines, 10 megawatts
of nameplate capacity, have been installed in Inner Mongolia in the last seven years.
Today, it is not difficult to find Chinese herdsmen whose wind-powered yurts (felt tents)
have small washing machines, TV sets, and even VCRs! Twice a year the nomadic Mongolian
herdsmen pack up all their belongings, including the wind turbine, and move to new
pastures.
How does wind power compare with other renewable energy technologies suitable for
decentralized rural electrification? Wind power is very competitive with
photovoltaics,
biomass, and diesel generators, but is usually more expensive than micro-hydro. It is also
very attractive for its jobs creation potential and the ease with which its technology can
be transferred to developing countries. In the big picture, wind power complements these
other power sources by providing a least cost approach under certain conditions. This
expands the scope of potential projects, pointing to the day when decentralized
electrification projects will be implemented on the same scale as current grid extension
projects. In many situations the lowest cost centralized system will be a hybrid system
that combines wind, photovoltaics and diesel power.
Aren't wind turbines too "high-tech" for rural people? The high technology of a
wind turbine is in just a few manufactured components such as the blades. A wind turbine
can actually be much simpler than a diesel engine. They also require substantially less
attention and maintenance. Our turbines, for example, have only three moving parts and do
not require any regular maintenance. They can operate for extended periods, five years or
more, without any attention. Our latest unit, the 1.5 kW BWC 1500, is designed for Village
Level Operation and Maintenance (VLOM), following guidelines established by the World
Bank. With training and spare parts, local users can support the wind turbine equipment
they use.
Doesn't it take a really windy area to make wind turbines effective, limiting their range
of application? Actually, the economies of scale in small wind turbines makes them
particularly competitive in cost for sizes above 250 watts. For daily loads as small as
one kilowatt-hour per day a wind turbine will be less expensive than diesels, grid
extension, or photovoltaics for virtually any wind resource above 4 m/s (9 mph).
This wind
resource is available in most of the developing world. For larger daily load requirements
the economics of wind power get progressively better. For a 10 kW wind turbine a wind
resource of only 3.5 m/s (7.2 mph) will usually make wind the least cost option.
There are not many areas of the world that have average wind speeds below 3.5 m/s
(7.2 mph).
Much of the wind data in developing countries shows average wind speeds in the 2-3 m/s
(4.5-6.7 mph) range; should wind still be considered? An all too common mistake made by
project planners is to predict wind turbine performance based on historical wind data
without first checking the reasonableness of that data. Meteorological services in
developing countries often collect wind data in the middle of towns from antique wind
sensors placed with poor exposure to the wind.
Thus, much of the available wind resource data from developing countries underestimates
the actual resource available in rural areas. Macro-scale data and analytical methods are
now available that can be used to check historical data for reasonableness. Accurate wind
resource assessment is a major impediment to large scale implementation of wind power in
many developing countries.
Would developing countries import U.S. wind turbines? They will import a few units, but
will eventually want to move to local production of the equipment. Small wind turbines are
not difficult to manufacture and they lend themselves well to technology transfer.
However, they are very difficult to develop and many companies and agencies have
underestimated the cost and time required to develop a reliable small wind
turbine. It seems a lot easier than it really is. A 5
megawatt per year small wind turbine production facility would cost under $1 million,
including licensing fees, which compares favorably to the $5-10 million figures that have
been quoted for photovoltaic factories of this capacity.
We believe that local manufacturing, under license or through a joint venture, is necessary if widespread utilization
is to be pursued. The developing country benefits from reduced foreign exchange
requirements, better support capabilities, local economic development and, usually, lower
production costs. The U.S. company benefits from fees, royalties and the sales of special
components. We have already licensed production of our units in Australia and
are considering similar arrangements in other countries. We have a joint venture
in China.
Does US-AID use, and encourage the use of, small wind systems and other
renewables? With a
few exceptions, such as the project in Morocco, the U.S. Agency for International Development
(US-AID) has continued to rely on diesel generators and grid extension in its projects. Even though
sustainability is often a key project goal, AID Missions have been very slow to
incorporate competitive renewable energy systems into their projects. Few of AlD's
fifty-odd overseas Missions have the technical staff to implement new technologies, so
the conventional approaches win out by default. Although AID missions will spend nearly
$400 million on energy projects this year, almost all of it will all be with fossil fuels.
There has been some solid improvement in renewable energy project activity at US-AID, but
clean energy is just not a priority.
Another barrier is an attitude among many managers at US-AID that aid and
trade don't mix. These people believe that trade promotion should not be factor
in developing foreign assistance projects, even when there is a clear benefit to
the project from using advanced U.S. environmental technology.
Is this typical of other donor agencies? Many other international donor
agencies take a much more
pro-active role in introducing renewable energy systems in developing countries and
facilitating technology transfer. European countries, in particular, have shown how donor
agencies and industry can work together to bring the benefits of renewable energy to the
world's poor. This often makes it difficult for U.S. companies to compete in developing
country markets even when they have superior technology. Fortunately, the situation at
US-AID is changing as environmental concerns increase and US-AID's awareness of modern
renewable energy technologies, including small wind turbines, improves.
How can I get more information? We would be happy to send you further information on small
wind turbines for developing countries or answer any of your questions. Just call or write
to Bergey Windpower Co. at the address below. You can also get further information on wind
energy and its use in developing countries from the American Wind Energy Association
(202-383-2500) or their web site: http://www.awea.org
You can learn more about the programs of the U.S. Agency for International
Development at http://www.us-aid.gov Bergey
Windpower Co., 2200 Industrial Blvd., Norman, OK 73069 USA T: 405-364-4212, F:
405-364-2078 BWC was formed in 1977 and has been manufacturing small wind turbines
since 1980. BWC wind turbines have been installed in all 50 states and approximately
90
countries. |
