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Egyptians had worshipped the sun for several millennia. In Ancient Egypt, Ra was worshipped as the God of the Sun. Now Egyptians are starting to harness the sun’s energy. According to the International Energy Outlook 2009 (available at: http://www.eia.doe.gov/oiaf/ieo/world.html) world energy consumption is going to increase by 44% until 2030. Even if Peak Oil were a myth (and it is not, it’s a reality, the question is not if but when we will reach it), there is no way to meet future energy demand without the large-scale use of renewable energies. As you can read in yesterday’s post (wind power for New York City?), offshore wind power is a good option for many regions in Europe and North America. For sun-blessed areas in Africa, Australia, South Asia, the southern United States as well as large parts of Latin America, solar power is the most promising bet for a secure and sustainable energy future.

Just 56 miles south of Cairo, a 140-megawatt combined solar and gas-powered plant is in its final phase of construction. The location is perfect due to the proximity of the large metropolitan area of Cairo and the year-round high solar radiation in the area. The plant comprises of an array of parabolic-shaped trough collectors which focuses solar energy on a pipe filled with a heat transfer liquid. The liquid reaches temperatures of about 400°C (752°F), evaporates and then powers a steam turbine which generates electricity.  In the night when energy demand is highest, a natural gas cycle kicks in to ensure a consistent supply of power. Natural gas is being burned to heat the heat transfer liquid  which continues to spin the turbine.

Solar Thermal Electricity has great potential. By 2020, the technology will have become competitive with oil and gas.

Under the Desertec concept, 15% of Europe’s energy consumption should be supplied by renewable energy sources, primarily from Concentrating Solar Power plants such as the one in Egypt, photovoltaic power generation as well as wind and hydro power.

Here’s a graphic that illustrates such a system:

http://upload.wikimedia.org/wikipedia/commons/7/71/DESERTEC-Map_large.jpg

Photovoltaic Energy (converting sunlight directly into electricity using solar cells) is even more attractive than Solar Thermal Energy for a number of reasons:

-  prices for solar panels are falling sharply while their efficiency is increasing.

- photovoltaic panels can be used on a small scale (e.g. by mounting PV panels on rooftops for decentral electricity production)

- grid parity - the point at which photovoltaic energy is equal or cheaper than grid power - is likely to be reached by 2015 in most of the United States. As soon as PV energy is cheaper than electricity from the socket, demand for PV panels will explode. Every homeowner could put some solar panels on his roof and thereby save a lot of money.

The sun is the only energy source that is inexhaustible. New inventions, improvements to existing solar power technologies and the cost reductions due to increasing production will help solar power to become an increasingly important component of our energy mix. Thin-film solar panels for external building walls, improved methods to store energy (e.g. the batteries of electric cars), rising fossil fuel prices and efforts to cut carbon dioxide emissions are all factors contributing to the future success of solar power.

http://www.arabenvironment.net/archive/2007/2/161471.html

This entry was posted on Wednesday, December 23rd, 2009 at 4:30 PM and is filed under Energy, Environment. You can follow any responses to this entry through the RSS 2.0 feed. You can leave a response, or trackback from your own site.