Thursday, October 15, 2009

Deserts and Nanotechnology Can Provide Clean Power and Water for 10 Billion

The global annual fossil energy consumption corresponds to the energy received by 5.7 hours sunshine in deserts. This is about 0.15 % of annually incoming radiation.  Solar power from deserts could supply electricity to 10 billion people in 2050.    

The technology exists to convert 15% of solar radiation into the useful energy form of electricity.  This means, that 1% of the area of global deserts would be sufficient  to produce the entire annual primary energy consumption of humankind as electric power. In other words: any conceivable global demand of energy, today or in future, could be produced from solar energy in deserts.

The DESERTEC Concept is an inter-continental project to supply sustainable electricity to Europe (EU), the Middle East (ME) and North Africa (NA) up to the year 2050. It shows that a transition to competitive, secure and compatible supply is possible using renewable energy sources and efficiency gains, and fossil fuels as backup for balancing power.   The project will harness the sun’s power, supplying the energy needs of that region as well as transporting power from Africa to Europe along energy superhighways (high-efficiency high voltage direct current lines). Spain is already using solar thermal plants, and they have also been in use in the U.S. for more than 20 years.

To this end red squares in the figure represent the accumulated areas for collectors typically needed to generate 17,000 TWh/y (terawatt hours per year) which is approximately the current world consumption, 3200 TWh/y (approx. EU-25 consumption), and 600 TWh/y (approx. Middle East/North Africa (MENA) consumption).

The square labeled “TRANS-CSP Mix 2050” indicates the space needed for solar collectors to supply the needs for seawater desalination and about two-thirds of the electricity consumption in MENA in the year 2050 and about one-fifth of the European electricity consumption by Concentrating Solar Thermal Power Plants (2,940 TWh/y in total)

The figure below shows Concentrating Solar Thermal Power Plants in the Mojave Desert.

Until 2020, the market for solar thermal power plants will show annual double-digit growth rates and attain annual sales of over $28 billion (EUR20 billion). In the future, the primary focal growth regions will be the U.S., South Africa, Australia, Spain, India, North Africa and the Middle East.  The developing and in particular the developed world depend crucially on the continuous supply of energy. The fossil fuel consumption in 2005 was 107,000 TWh/y.

If desalination of sea water is powered by solar energy instead by fossil fuels, its environmental impacts are significantly reduced. However, seawater desalination itself is always a considerable burden to the environment, due to the resulting salty brine and the necessary chemical water treatment. Nano-filtration of intake water can mitigate those impacts, but more energy is required in that case. Therefore, activating the existing potential for enhanced efficiency of water use, water management and infrastructure is also a very high priority, in order to minimize the need for desalination. The European AQUA-CSP study analyzes the environmental impact of a broad application of solar-powered seawater desalination to cover the expected freshwater deficits.

Siemens AG is acquiring the solar thermal power company Solel Solar Systems Ltd. to bolster its position in renewable power.  Solel has a workforce of over 500 and is one of the world´s two leading suppliers of solar receivers, which are key components of so-called parabolic trough power plants. The high-growth company, which posted revenue totaling almost $90 million in the first six months of its current fiscal year (January 1 to June 30, 2009), is also a leader in the planning and construction of solar fields. The purchase price is about $418 million.  Since 2006, Solel has also been present on the Spanish market, supplying key components for 15 solar thermal power plants with a combined capacity of 750 megawatts. In addition, the company is also active in the U.S. market. The transaction which much receive regulatory approval is expected to close before 2010.

1 comment:

  1. Sea Water Greenhouse technology has huge potential. Brine from the process can be evaporated in evaporation pans. Pipeline from sea utilizing solar power for pumping. Areas near sea should be developed first because of economy of sea water delivery.