Can the Sahara Power Europe?

One of Europe’s most precious natural commodities could be situated right across the Mediterranean – the Sahara Desert. The Sahara desert has long been regarded a vast expanse of scorched earth with no practical application. Now its immense solar potential is causing scientist to predict that it could power Europe for centuries.

The sweltering Sahara desert’s 8.6 million square km (3.32-sq. - mile) parched wasteland has enough light falling on it to easily power Europe and Africa. Just 0.3% of all light falling on the Sahara and Middle East could supply all of Europe’s energy needs. Temperatures soar over 45° on some afternoons, making it the world’s ideal solar energy deposit.

Scientists started calculating the solar power of the Sahara a few years ago and the results were astounding. Theoretically, less than 1% of the Sahara deserts area (90 600 square km or 35000-sq.-mi) could generate as much electricity as all the power plants in the entire world combined. 15500 square km (35 000-sq.-mi.) could provide electricity for all of Europe’s 500 million people.

Solar panels used in households will not be used. Concentrating solar power (CSP) will be used. CSP uses mirrors to focus light on water pipes or boilers. The water evaporates into steam and this steam is used to operate the turbines or generators that create electricity. This technology has been around for a long time and has been used to produce power in California’s Mojave Desert since the 1980’s. Three British companies are part of the Sahara Forest Project and they propose that the power plants be built in depressions in the land that are under sea level. This will allow seawater to flow into them and cool the plants while also cleaning the mirrors. Wastewater would irrigate areas around the power stations and this would create verdant oases – this is where the “forest” in the group’s name comes from.

But all this will require a lot of infrastructure. A vast collection of pipes, mirrors and power lines will span across hundreds of kilometres of arid terrain. Gerry Wolff, an engineer heading DESERTEC, an international consortium of solar-power scientists, estimates that $59 billion will be required to start transmitting power to Europe by 2020.

There are many more financial drawbacks. Europe’s entire power grid must be changed. The power lines are designed for coal-fired plants and inadequate for such a large load of power. More than 19300km (12000 miles) of high-voltage direct current (HVDC) lines would also be needed. Germany’s state run Aerospace centre estimates that replacing the entire power grid would mean that $465 billion would be required to start sending considerable amounts of electricity to Europe in the next 40 years. CSP technology also only works in high temperatures and a sudden drop in temperature could cripple power supply. Power stations would be so far away from civilization that maintenance would be very difficult.

The sheer financial implications of such a project have severely dampened this from occurring. Many governments are ignorant of the use of solar energy. This idea could become more feasible if small amounts of energy are transmitted below the Mediterranean by pre-existing developments. Solar plants are already being built in Algeria, Morocco and Egypt. If these prove a success, more companies could follow.

$465 million may seem a lot, but the US government’s bailout plan was $700 million, let alone the $1 trillion national stimulus package. If this project does get off the ground, there might be a second man-made structure visible from space.

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References

1.German Aerospace Centre
2.German Aerospace Centre

Out of Africa
Vivienne Walt (26 January 2009) Out of Africa. TIME. P. 38

Background Image:
Nadine Y. Barclay, 2008, On 140 acres of unused land on Nellis Air Force Base, Nev., 70,000 solar panels are part of a solar photovoltaic array that will generate 15 megawatts of solar power for the base.