Over 200 000 MWh/year of wind generated electricity are currently being produced by some 90 Wind Turbines of the 600 kW range. If this production was to be supplied by a Coal fired power plant, some 230 000 Tons of Carbon Dioxide would have been released in the atmosphere. To sequestrate this amount of carbon, the planting of over 12 million trees would have been necessary.
As for the natural habitat, large corridors have been provided for migratory birds to pass through. Statistical surveys have now revealed that the impact of the wind turbines on the local environment has been negligible.
The more recent "Amogdoul" 60 MW wind farm started operation on April 13th 2007. Amogdoul is the ancient name of the city of Essaouira next to which this wind farm is located, some 400 Km South of Casablanca on the Atlantic coast.
Utilizing the most western capes of Morocco’s central Atlantic coastline (cape Sim) where Trade Winds can be tapped on these Northern latitudes, the Amogdoul wind farm is expected to produce some 210 GWH of electricity, and enable the reduction of 156.000 tonnes of CO2 emissions per year. Configured with 71 individual 850 MW Wind Turbines, the project also benefits from the Clean Development Mechanism (CDM) support sources associated to environmental agreements from the Kyoto protocol.
Spanish government has accorded Morocco a loan amounting to 100 million euros (135 million U.S. dollars) on the construction of the Tanger Wind-Energy Park. The funding came from the Development Assistance Fund ( FAD). The loan, which is repayable within a period of 20 years, has an eight-year grace period and will attract an annual interest rate of 0.5 percent.
The Tanger Wind-Energy Park, with a production capacity of 140 MW, will comprise 165 aero generators capable of producing 526.5 Giga Watt Hour (GWH) annually. The park will help meet Morocco’s rising energy needs, which grow at a pace of about eight percent annually, and also help towards achieving Morocco’s goal of producing 1,000 MW of clean energy by 2012.
Background on the Sahara Wind Project
If we take the growing need for electricity worldwide, its environmental impact and the current energy trends in Europe, wind power which represents an inexpensive source of renewable energy, seems to provide one of the best alternatives to supply one the world’s largest electricity market. The development of wind power is a European success story, and its potential may be big enough to cover all of the continent’s electricity needs.
However, land based electricity production from wind is rather limited in Europe due to a relatively high population density and its corresponding intensive use of land . This leads to significant reductions of usable lands on which the wind resource can be exploited. In Germany for instance (one of the World’s leader in wind power), the wind energy potential is limited in comparison to the need of its large domestic power consumption, and would already imply the successive use of worse sites where annual wind productions are low, resulting into higher electricity costs. If the growth rates remained as high as they were a few years ago (they have since dropped significantly) most of the productive sites would have been already equipped. Such perspectives could leave a growing wind energy industry with a notable deadline that may prevent it from having any significant impact on a more sustainable European energy supply scheme.
While Germany and Denmark were pioneers, other European countries like Spain could be faced with the same difficulties. Thus, and in order to sustain the future of a promising energy technology, other alternatives are currently being sought such as to utilize offshore wind potentials. In Europe however, there are large industrial regions, if not entire countries, with high energy consumptions that don’t even dispose of an access to the sea.
It is therefore conceivable that some countries would consider importing significant amounts of low-cost wind generated power from other windy regions. There are huge areas with excellent wind conditions around Europe where population densities are one hundredths that of Europe, and where the same can be said about electricity needs.
The Saharan coast from Morocco to Senegal represents the most extensive, windiest and least populated region worldwide that is reached by the European electricity grid. An expected yearly production of more than 4500 Full Load Hours can be derived at some sites, where recent wind measurements were made.
The size of the wind catchments area is huge as the sole coastline, just to mention, spreads for over 2000 Km (1250 miles)
Considerable amounts of wind generated electricity could be transferred using optimized grid infrastructures. In order to avoid unacceptably high losses, High Voltage DC techniques could be engaged as for large capacities exceeding 5 GW, existing technologies can limit transfer losses at full load, to less then 10% over 3000 Km (1800 miles). This distance is long enough to deliver wind generated electricity from the Saharan plateaus of Tarfaya to Germany.
The existing Euro-Mediterranean economic framework is likely to enable this vast wind energy source to become one of the main economic drivers of a sustainable development for the entire region. Taking advantage of the relative proximity of both continents to tap into a widely available clean and renewable power source serves two complementary objectives, namely to satisfy growing European energy needs while strengthening North Africa’s integrated industrial, social and economic take-off.
The North Atlantic Trade Winds
In the equator large hot air masses rise to the upper layers of the atmosphere and move towards the Poles (Earth’s higher latitudes) where the temperatures are colder. In the Northern Hemisphere, at around 30° latitude because of the rotation of the Earth (the Coriolis force), these air masses are deviated clockwise and begin sinking down creating a high pressure area (called Anticyclone) over the North Atlantic Ocean.
Hence, winds generated over the equator revolve clockwise around the North Atlantic Ocean’s high pressure area. Since they are largely driven by the globe’s temperature differences which translate into atmospheric pressure differences, these winds are considered global winds.
The "trade winds" as they are being called are not influenced by any topography nor surfaces on the earth. They result from the combined influence of the rotation of the earth and its temperature differences which are due to Solar radiation incidence angles that cannot be the same on the earth’s equator versus its poles. It may be relevant to mention that these Astrophysical planetary fundamentals cannot change, regardless of any climate change considerations, so long that the earth is round, that it is spinning and that the sun exists.
Close to the African coast, the junction of the Sahara desert with the Atlantic Ocean creates a zone of global energy exchange were the climate is dominated by these steady winds. The thermal winds generated locally over the Sahara’s hot surfaces are actually superimposed upon the larger wind system generated over the Atlantic. This creates one of the largest and steadiest wind systems available on earth.
The North to North East wind directions are the results of these global and local effects that are typical for a Trade Wind region. The Trade Winds are actually the main factor responsible for the Sahara’s extreme dryness by moving away the clouds from the ocean. They have been known for centuries in transatlantic sailing routes.
The Trade Winds have shaped the vast majority of the Saharan coastline from Morocco through Mauritania into inert rocky plateaus, called "Hammadas". Wind speeds have been accurately monitored on different sites for several years.
Wind Energy Potential
The annual production that can be produced from wind force in good wind regions, with large wind parks can be as high as 0.1 to 0.15 TWhel/km². The establishment of wind turbines with a power density of 7 MW/km² could produce about 0.028 TWh/km² per year in good locations in South Morocco. Although close arrangements of wind turbines tends to weaken the global supply of energy of a Wind Park, wide space availability for large-scale wind installations enables an optimal wind turbine spacing ratio to be applied.
A wind turbine spacing of only 2.4 MW/km² on parts of the 2000 kilometers long coastline from Morocco to Senegal could potentially generate a production of more than 1000 TWh per year. This would be sufficient to cover close to half of the entire electricity needs of the European Union estimated at (2300 TWh).
This very large potential represents several dozen times the electrical requirements of the North African countries combined, and cannot be utilized locally. The distances of North African electric load centers are indeed quite remote from this region. The access to these renewable energy potentials requires the use of different technologies currently available only for much higher energy transfer capabilities, that the size of North African load centers simply cannot absorb.
High Voltage Direct Current (HVDC) transmission lines for instance, would allow vast amounts of electricity (in the GW range) to be transported from North Africa into a Euro-Mediterranean electricity market at minimal losses. Hence, a significant share of Europe’s wind energy production would be complemented by the use of these large productive sites, making wind energy more affordable.
Comparative advantages rather than a mere displacement of European wind energy productions would be achieved, as the High Voltage Direct Current (HVDC) transmission technologies used would contribute to stabilize surrounding grids on both ends, enabling them to integrate more wind energy locally. The advantages of integrating wind resources on a continental basis become even more obvious, as the seasonal distribution of winds in terms of peak power productions are quite complementary. While winter highs are characteristics of European wind energy generations, the Saharan Trade Winds have their peak production in the summer season. This is particularly relevant in Southern Europe where the tourism driven economy induces higher electricity consumptions at this time a year. These could be matched by a carbon-free renewable source of wind energy generated at competitive prices.
These perspectives highlighted by our 5000 MW Sahara Wind Energy Development Project Platform presented at the European Parliament in 2002, would also contribute to improve the economic prospects of marginal desert regions that currently dispose of very limited endogenous development possibilities.
The Sahara wind resource that spreads through thousands of kilometers of desert seacoasts, will take many years in order to be accurately evaluated. It represents probably one of the world’s largest untapped sources of wind energy. The size of this territory, the availability of the wind, and the geographical proximity of this region to Europe as one of the world’s largest integrated electricity market provides encouraging development perspectives for the future of renewables in this area and beyond.
High Voltage Direct Current technology (HVDC)
With the available transmission technology today, the prospect of importing renewable electricity from remote and thinly settled regions is economically viable and technically feasible. High Voltage Direct Current transmissions have a high availability and reliability rate, as shown by over 50 years of operation. For large electricity transfers, High Voltage Direct Current technology (HVDC) enables very fast control of power flows which implies stability improvements not only for the HVDC link but also for the entire surrounding AC system.
At present, more than 70 GW of electric capacity are being transmitted through High Voltage Direct Current transmission lines in over 95 projects world wide. Their main purpose is to actually transfer large amounts of hydro-power from remote sites to urban or industrial centers with high demands for electricity. Among these projects we could mention that of Itaipu in South America or the one linking the North Eastern United States (New England including New York City) that is currently fed with low-cost hydro-electricity generated out of Canada’s large power dams located more than three thousand kilometers away (1900 miles). This distance actually represents a length of transmission lines that would be long enough to connect North Africa’s Sahara desert wind resources to the middle of Europe.
The existing High Voltage Direct Current (HVDC) technology enables large electricity transfers to limit cumulative line and AC-DC-AC converting losses, to less than 15% over a distance of 3500 km. Whereas the overall added costs per kilowatt/hour for such a long transmission line are lower then € 0.02/kWh. The integration of North Africa’s most suitable wind resources to gradually supply the European electricity grid with low costs wind-generated power is technically feasible and would enable significant economies of scale to be achieved.
Economics of Wind Power
Compared to Germany’s 1900 hours of wind power production per year, a rather conservative average production figure in the coastal Saharan region would be in the range of 3400 Full Load Hours due to the exceptional quality of the Trade Winds. Taking a price of 1000 €/kW of rated Wind Turbine capacity, 5 % real interest rate, 20 years lifetime, 2% of total investment as annual Operation & Maintenance costs, the wind power generated there costs under 3.0 €cent/kWh. From the single wind measurements available within this territory, we would actually come to significantly better results, as at selected sites a yearly production of more than 4500 FLH can be derived.
To transfer the power from the region of Tarfaya, the northern part of this area, to the center of Germany for example, the length of a HVDC line would be 3500km (incl. 28km sea cable). For this case, the total costs of wind generated electricity from the Sahara desert delivered all the way to Germany are calculated to be 4.4 €cent /kWh. Thereof 0.4 €cent/kWh are due to the losses of 10% if done with a HVDC line of about 5 GW capacity. One would expect even greater production figures as the most productive sites would be utilized for such projects.
By their large-scale application inside the EU, the specific costs of wind turbines have been divided by 4 in the last 20 years. The price of the installed capacity will be probably lower than 1000 €/kW that has been assumed for the aforementioned project. Already in the year 2000 with less than 1 GW of capacity installed, Spain managed to drop its average installed wind power costs down to 850 €/kW. Due to the current frenzy in wind turbine demand these prices have come up significantly since, whereas availability is scarece and delivery schedules extremely long.
Also, the wind turbines used in the Sahara desert would not necessarily need to have the same costly design features such as low rotational speed to reduce noise and visual nuisance required for all wind turbines currently installed in the densely populated areas of Europe. On such large scale projects roughly equivalent to half of Spain’s entire wind power capacity, local manufacturing of specific wind turbines would enable significant economies of scale to be made.
Wind Energy Market Developments
Instead of expanding into new markets in order to take advantage of better conditions available through wider regional synergies, the European wind power industry focuses its development on off-shore wind potentials. Even if not applicable to every EU country, this option enables wind developers to overcome most limitations hampering the expansion of wind power in Europe. Since this industry has thrived on subsidized premium prices paid for wind generated electricity available in Europe, the costly off-shore wind option reinforces further the justifications for sustaining higher prices.
Consequently, the current research trends in wind turbine design tend to favor the development of larger, sometimes gigantic machines aimed at reducing the costs of sea foundations for individual Off-Shore units. Its important to mention that neither export of wind turbines nor their integration in developing countries is achievable under these circumstances as 65% of the world’s wind power market remained located within the EU.
The concept of utilizing the Saharan Trade Wind resource could provide an ideal development setting at a critical time for the wind energy industry to expand most comprehensively into developing countries. The levels of incertitude due to recent drops of wind turbine orders coming from Germany and Spain that are progressively shifting to the US and Asian markets tend to confirm these forecasts.
As it seem to spread geographically ever closer, the wind power industrial growth that was initiated in Denmark, Germany and most recently in Spain, demonstrated the importance that the Trade Wind resource will have for an integrated economic development of this region. In the Sahara desert coastline, large wind power generation facilities could provide ideal grounds for the wind industry to expand in a more sustainable way into the developing wold by reinforcing local industrial activities.
Indeed, the Spanish wind energy industry demonstrated that the transfer of manufacturing capabilities from Germany and Denmark enabled significant cost reductions on domestically installed wind power capacities. Building upon such experience, the price of wind power generated in exceptionally good wind regions through dedicated machines, manufactured and erected locally with lower labor wages are bound to become more competitive.
The integration of Wind energy in an economically competitive setting that would cover the transfer of industrial capacities in the region would contribute to enhance the energy security of Europe and North Africa quite significantly by diversifying their current supply sources by renewable energies that are more complementary and sustainable then any other alternatives.
Since wind turbines represent over 80% of investments of the Sahara Wind Project (20% remaining for the HVDC lines), these dedicated low-cost and reliable wind turbines could have a considerable price impact on the economics of the Project, enhancing thereby its competitiveness. Furthermore, a Project the size of Sahara Wind’s is likely to enable the development and manufacturing of machines that will be much better suited to address the challenging electrification needs of most developing countries.
ec.europa.eu/research/energy/pdf/gp/gp_events/wrec/wrec_2008_wind_khalid_benhamou_en.pdf
www.lse.ac.uk/collections/EWE/NATO%20presentations/NATO_LSE%20Zejli.pdf
www.ewec2007proceedings.info/allfiles2/11_Ewec2007fullpaper.pdf
