Potential for Ethiopia to Produce and Export Renewable Energy
Jan 19, 2011 - Harry Valentine - EnergyPulse.com
Several years ago the European group called Desertec developed a strategy
to generate renewable energy resources across the Middle East and North Africa
(the MENA) and export the electric power into Europe. The range of technologies
included wind, solar-PV, solar-thermal, hydroelectric, geothermal, ocean wave,
ocean tidal currents and biomass sources. The original Desertec plans focused
on developing the renewable energy potential of MENA nations located to the
north of 15°N, until the South African Eskom Group initiated discussions
about beginning development of the hydroelectric power generation potential
of Inga Falls on the Congo River. Peak demand for electric power occurs between
May and September across Europe, the MENA and South Africa due to electrical
heating of buildings during the southern winter.
The South African plans called for HVDC power lines radiating south across
Africa to South Africa, northwest through Algeria and Morocco and across
the Spain as well as northeast toward Egypt. Then the Congolese government
to reconsider the prospect of developing a hydroelectric project estimated
at average of 40,000MW to 45,000MW output with peak output pf 100,000MW between
October and March. While Congo reconsiders their options and Eskom considers
the potential for new hydroelectric development on the Zambezi River (peak
output between October to March), Ethiopia announced that they might have
some 45,000MW possible generating capacity that includes 30,000MW of hydroelectric
power between May and September, wind (10,000MW) and geothermal (5,000MW)
Ethiopia's Power Potential:
Some of the tributaries of the headwaters of the Nile River flow through deep
valleys located in the Ethiopian Highlands. The width and depth of these valleys
allow for the construction of large reservoirs that could store water for hydroelectric
power dams. There are also several suitable mountain valleys in the southern
Highlands that could also allow for the development of large storage reservoirs
that would supply hydroelectric power dams.
Prevailing winds blow across the Ethiopian Highlands in a southwesterly direction
during the cool, dry season and in a northern/northwesterly direction during
the hot, humid and rainy season. Humid summer winds blow through mountain
valleys at substantial velocity, where it may be possible to install wind
turbines on high towers that are stabilized from the valley walls. It may
also be possible to suspend arrays of transverse-axis wind turbines on
cable systems across suitable valleys.
There is potential for geothermal energy in eastern Ethiopia and Eritrea.
While it is possible to drive steam turbines using hot geothermal steam,
be scope to superheat the steam using concentrated solar thermal energy.
Geothermal energy from large geothermal wells at some 80°C to 140°C may be used
to energize air-based chimney engines and vortex engines rated at 50MW to 300MW.
During humid summer weather, the operation of these engines would propel humid
air upward into the cooler regions found at higher elevation, where the moisture
droplets may coalesce into rain droplets.
Ethiopia has in recent years been involved in a military skirmish with their
neighbor to the southeast, Somalia as well as with their neighbor to the northeast,
the now nominally independent Eritrea. Egypt has warned about hydroelectric
power dams upstream along the Nile River in the event that such development
reduces the volume of water that Egypt receives. Dams and reservoirs built
with a large water surface area have a propensity for increased evaporation
and seepage into aquifers that can reduce water flow volumes downstream.
Sudan and Ethiopia need to ensure that Egypt receives enough water should
either nation develop additional hydroelectric generating capacity. Ethiopia
would need to develop mutually cordial and cooperative diplomatic relations
with neighboring states in order to peacefully and productively develop their
renewable energy resources.
Increasing Summer Precipitation:
Some of the highest mountains across sub-Sahara Africa occur in Ethiopia with
elevations exceeding 7000-ft above sea level. Summer humidity reaches 100%
across Ethiopia as prevailing summer winds blow across the Seychelles region
of the Indian Ocean and pick up moisture that is then carried over the Ethiopian
Highlands. There are numerous technologies that promise to increase the rate
of condensation at higher elevations in humid regions.
Some 60-years ago, the head of the South African weather bureau, Dr Theodore
Schumann theorized that humidity passing through an electromagnetic field would
condense. He proposed to install a demonstration project at the top of Table
Mountain near Cape Town. Inventors in Latin America installed fine-meshed fog
or dew fences across valleys that faced the Pacific Coast and through which
humid wind would blow. The fog or dew fence is now a proven method of extracting
water from humid air.
Researchers in China have experimented with using low-frequency sound waves
to activate the moisture droplets in humid air, causing them to coalesce into
droplets of water. The combination of sound waves and dew fences offers one
option by which to increase precipitation in some areas of Ethiopia. The addition
of the South African electromagnetic field approach may further increase the
amount of water that can be extracted from the stream of humid air.
Wind turbines churn and swirl the air causing warmer air at a lower elevation
to mix with cooler air at a higher elevation. Winds blowing from the Irish
Sea on to England's northwestern coast have turned to streams of fog after
passing through the blades of coastal wind turbines. Horizontal-axis wind turbines
mounted on towers quite naturally produce low-frequency sound waves and some
refinement to their operation at higher elevations could result in them generating
electrical energy while assisting humid air to coalesce into rainfall.
Solar chimneys and vortex engines are relatively recent, experimental air-based,
solar thermal power technologies that draft air through turbines that drive
electric generators. These engines may be powered by concentrated solar energy
focused by an array of mirrors or captured by saline ponds. They may operate
on low-grade geothermal energy. The operation of these engines propels warmer
humid air from ground level into the cooler atmosphere at higher elevation,
where there is greater potential for the moisture droplets in the humid air
The solar thermal air-engines pull air through ducted wind turbines that may
be tuned to produce the frequency of sound waves that would cause moisture
droplets to coalesce in the cooler air at the higher altitudes. There may be
potential to combine all 5-methods of water extraction in various locations
across Ethiopia, to increase the amount of liquid water than can be extracted
from the humid air streams that blow across that nation. The objective would
be to ensure that neighboring nations receive a steady supply of potable water
while Ethiopia generates hydroelectric energy.
Pumped Hydraulic Storage:
The Danakil land depression covers some 3800-square miles along the Red Sea
coast of Eritrea and stretches into Ethiopia. The region is a source of rock
salt with potash mines located around the land depression that measures up
to 148-feet below sea level. There is potential to partially flood the Danakil
land depression and operate it as a seasonal pumped hydraulic energy storage
system. Seawater would flow in during summer to generate up to 3000MW of hydroelectric
power as its depth drops from 60-feet below sea level to 80-feet below sea
The seawater would be pumped out during the winter months using energy mainly
from excess off-peak wind energy from across Ethiopia and the MENA plus future
electrical energy from the Inga Falls hydroelectric installation. Future off-peak
tidal power from kinetic turbines installed under the Strait of Bab-el-Mandeb
may also be transferred into pumped storage at the land depression. During
winter, the Equatorial Counter Current flows in the anti-clockwise direction
in the northern Indian Ocean and produces a stronger tidal current through
the Strait of Bab-el-Mandeb.
Flooded Danakil Land Depression:
Dropping winter water levels in the flooded Danakil land depression would
allow for the installation of saltpans around the land depression, to collect
salt for market. The flooded land depression will also provide increased evaporative
surface for winter winds that blow in from the Red Sea toward the southwest.
During winter, the surface area of the lake may drop from 3800-sq.mi to around
2000-sq.mi. The 125-mile wide band of wind that blows across some 25,000-sq.mi
of Red Sea surface would also blow across an added 8% of evaporative water
surface that would be much shallower than the Red Sea.
The surface elevation of the flooded land depression would be below that of
the Red Sea and in a warmer region. Seawater stored in the land depression
could increase in salinity and capture more of the infrared solar spectrum,
causing the water to heat more rapidly to a higher temperature than the Red
Sea. Winter evaporation could increase some 10% to 20% per unit area, adding
some 18% to 30% more moisture to the band of wind that blows inland from the
Red Sea and over part of the northern Ethiopian Highlands. It may be possible
to operate technology in this region that may produce some winter rainfall
over the watershed area of the Blue Nile.
The higher salinity of the flooded land depression would divert more solar
heat to the lakebed and raise its temperature. That heat could become the source
by which to operate air-based solar-thermal chimney engines and vortex engines
of 100MW to 300MW output each. The operation of these engines could pump humid
air to higher elevations with the potential to produce winter rainfall in areas
of Ethiopia that lie to the west of the flooded land depression.
The Somali Question:
Somalia lies to the east and southeast of Ethiopia, with 2-main rivers, the
Juba and the Shibeli flowing across the border into Somalia and to the Indian
Ocean. Any attempt by Ethiopia to build hydroelectric dams in the large valleys
through which the headwaters either of these rivers flow, would require the
involvement and cooperation of Somalia. Dams built along the headwaters of
these rivers have the potential to increase evaporation and seepage, possibly
reducing water flow volumes into Somalia.
One possibility would be to explore methods and install technologies by which
to increase precipitation over the watershed areas of the rivers that flow
from Ethiopia into Somalia. An alternative approach would be to develop ways
to reduce evaporation from the dams, perhaps by installing some form of UV-resistant
cover that can float on the water surface.
During winter, prevailing winds blow over the Gulf of Aden toward northern
Somalia and southern Ethiopia. During summer, prevailing winds blow from the
Indian Ocean toward southern southwestern Somalia and southern Ethiopia. The
present social and political situation in Somalia has stalled development of
electric power and water resources.
Ethiopia will need foreign investment to develop their vast capacity for cost-competitive
electric power generation, energy storage and to introduce feasible methods
by which to increase precipitation. The market for cost-competitive renewable
energy will include such nations as Sudan, Egypt, Kenya, parts of Europe and
parts of the Middle East along with potential to export electrical energy as
far south as South Africa. Ethiopia will need to balance the volume of water
it will store in their future reservoirs while ensuring that sufficient volumes
of water flow downstream, for the benefit of other nations.
Ethiopia will need to negotiate cooperative agreements with neighboring nations
that will include Eritrea, Somalia, Sudan, Kenya and Egypt. There have been
serious political tensions between Ethiopia and Eritrea and also between Ethiopia
and Somalia. Ethiopia's plans to develop their potential hydroelectric resources
have become a cause of concern for neighboring nations downstream along the
Nile. A neutral outside mediator could assist in developing mutually cooperate
agreements between Ethiopia and several other neighbor nations.
China is assisting Sudan in the development of their oil industry, China has
assisted in the development of an automobile factory in Egypt and several other
African economies to develop various other manufacturing industries. China,
South Africa and several European nations administer a neutral foreign policy
across Africa and the Middle East while pursuing mutually cordial diplomatic
intergovernmental relations with governments in that region. China and South
Africa are in a position to fulfill the role of a neutral mediator with the
objective that Ethiopia may generate electric power for local use as well as
for export to neighbor nations while assuring that sufficient water volumes
flow from Ethiopia into the Nile, Atbara, Juba and Shibeli rivers.
Attracting Foreign Investment:
Ethiopia's economy and population neither has the means by which to fund the
development of electric power generation capacity inside their nation, nor
does it have the capacity to subsidize the operation of photovoltaic installations
or other forms of energy conversion. Economic conditions would restrict a future
power industry in Ethiopia to operating unsubsidized, feasible power generation
technologies and export a substantial amount of that power to neighboring nations.
The willingness of Ethiopia's government to allow private power generation
to operate in their nation over the long term, with property protection rights
will determine the future development of potentially feasible renewable power
generation technologies across that nation. Such a condition would set the
stage for investors from across the Middle East and Asia to consider the option
of developing viable renewable energy power generation in Ethiopia.
There is increasing demand for electric power across Africa, Europe and the
Middle East with an evolving preference for feasible power from renewable sources,
especially hydroelectric. Africa has much undeveloped potential for seasonal
hydroelectric power along the headwaters of rivers that flow from the Ethiopian
Highlands, Inga Falls on the Congo River, valleys along the Zambezi River as
well as undeveloped hydroelectric power in Nigeria. Investors and developers
from India are already exploring the potential to develop the electric generation
capacity of Nigeria in exchange for oil from Nigeria.
The development and operation of mainly seasonal hydroelectric power generation
would require access to seasonal energy storage, including pumped hydraulic
storage in land depressions such as the Danakil, the Qattara Depression and
the Dead Sea. The latter 2-land depressions have been the subject of much research
related to power generation and energy storage. The advent of high-efficiency,
high-capacity HVDC power transmission technology opens the door to future development
of renewable energy resources in Ethiopia, along the Congo River, Zambezi River
along with seasonal energy storage.
Hydroelectric development in Ethiopia will have to include methods by which
to increase rainfall from the humid summer air, to ensure neighbor nations
downstream of sufficient water in rivers that flow from Ethiopia. A neutral
mediator such as China could assist Ethiopia and neighboring nations to resolve
differences and concerns while cooperating to their mutual benefit to develop
renewable power generation and a power transmission system across the region.
Peak hydroelectric power generation in Ethiopia would coincide with peak demand
for electric power in the neighboring nations.