Merging CSP with huge greenhouses could bring tremendous benefits to the MENA region – if the will is there

By CSP Today staff writer 

CSP plants could help solve water scarcity in the MENA region by powering seawater desalination, either by means of electricity or in combined generation with process steam.  

Using solar thermal power plants for desalination and production of electricity, and combining it with agricultural projects, makes sense in such regions, where a huge amount of energy is available via irradiation.  

Each square kilometre of land in the MENA region annually receives solar energy equivalent to combusting 1.5 million barrels of crude oil, an amount sufficient to desalinate 165,000m³ of water per day, according to The Climate Institute. 

“The technical potential, especially in North Africa, is immense and such concepts could lead to a bright future for these regions. The ‘fuel’ and ‘feedstock’ for such concepts are free of charge: seawater and sun,” says Dr Günter Schneider, managing director, Enolcon GmbH. 

Saharan promise

One of the promising initiatives in the news is the Sahara Forest Project. It proposes a combined CSP/Seawater Greenhouse operation, located some distance from the coast in a desert region. The Seawater Greenhouse is a new development offering sustainable solutions to the problem of providing water for agriculture in arid, coastal regions. 

The installations would turn deserts into lush patches of vegetation, according to its designers, and without the need to dig wells for fresh water, which has depleted acquifers in many parts of the world.  

“There are several very interesting concepts under development and pilot projects in preparation,” said Dr Schneider. 

Several benefits can be reaped by combining the Seawater Greenhouse concept with CSP technology. For instance, the CSP systems need water for cleaning the mirrors and for the generation of steam to drive the turbines, which the greenhouses can provide.

The scheme is proposed at a significant scale (so that very large quantities of seawater can be evaporated). The greenhouses are arranged as a long ‘hedge’ to provide a windbreak and shelter to the outdoor planting scheme, and to maximise the area of evaporation. If the location is at or below sea level, pumping costs are minimised or avoided altogether. At intervals along the ‘hedge’ of greenhouses, CSP arrays would be installed. Along the windward edge of the greenhouses an elevated CSP parabolic trough collector would provide added benefits to the Seawater Greenhouses by acting as wind catchers. 

Political hurdles 

Aside from various technical issues, such projects need to be financed in a sustainable way and the political background must enable implementation, Dr Schneider says.

Also, there is still a long way to go before enough industrial capacity is available to serve the demands of such huge concepts.   

Major hurdles impeding the growth of the CSP sector vary depending on particular markets or regions.  

For the MENA region, the current scenario requires improvements on several counts – be it support from the government, feed-in-tariffs and grid connection points/transmission of electricity. 

“It is a mixture of all such necessary factors. Of course, the weight for each factor might differ from country to country and project frame conditions,” added Dr Schneider. 

He added that without a clear commitment from the government and the “open minded” management of the grid operator, a CSP project would have no chance of being developed and implemented successfully.  

As a second level, to ensure that such projects are financially attractive, this can be arranged via feed-in-tariffs, cheap loan conditions or other financial tools.  

There are quite a few interesting technologies under development, which got financing to reach a certain development stage, but their technology does not yet have the status of ‘proven technology’.  

According to Dr Schneider, one of the biggest hurdles is being able to show lenders and investors that the technology is ready for commercial application in the long-term.  
 

Efficiency gains

In solar thermal power plants, only about 25% of the collected solar energy is converted into electricity. If combined with seawater, another 50% of the collected energy, normally released as heat, can be used for desalination. This way, up to 85% of the collected solar energy can be used, and with each TWh of power, 40 million m³ of water can be desalinated in cogeneration. 
 

CSP, CPV and Thin Film Summit MENA 

Dr Günter Schneider, managing director, Enolcon GmbH is scheduled to speak at the CSP, CPV and Thin Film Summit MENA, scheduled to take place in Abu Dhabi in June (2-3) this year.  

For more information, click here:

http://www.newsolartoday.com/mena09/agenda.shtml 

or Contact: Sara Lloyd-Jones by email sara@csptoday.com