Iran is introducing the latest solar technologies to cut its oil consumption and bring cheaper electricity to its civilians
by Alok Jha
Renewable energy experts in Iran have been quietly working on capturing sunlight to power their country.
According to officials, Iran has started 2009 by inaugurating a pilot solar plant in Shiraz, Fars province. It is a concentrating solar power (CSP) system, using parabolic mirrors to focus sunlight onto a tube of water that is super-heated to make steam that is then used to turn electricity-generating turbines.
According to the Mehr Iran news agency, Iranian energy minister Parviz Fattah said: "The country backs the use of alternative and renewable energy sources. In future alternative energy sources will be greatly developed in the country. The growth of investments in this sphere is expected."
The solar radiation hitting the Earth contains around 10,000 times the energy needs of the world's population. CSP is seen by many as a simpler, cheaper and more efficient way to harness the sun's energy than other methods such as photovoltaic panels. But it only works in places with clear skies and strong sunshine. As such, large CSP plants of up to 20mw each are already in construction in the sunnier parts of the world.
Spanish firms, in particular, are moving quickly with CSP: more than 50 solar projects around Spain have been approved for construction by the government and, by 2015, the country will generate more than 2GW of power from CSP, comfortably exceeding current national targets. The companies there are also exporting their technology to Morocco, Algeria and the US.
At present the Iranian plant is small (just 250KW, probably enough for just over 200 family homes while the sun is shining) but the locally-built mirrors join thousands of smaller-scale solar-thermal installations already in place around the country.
Whether Iran has plans to build bigger solar plants or add photovoltaic panels to those plans is unclear, but an ambitious move in this direction would be a good idea. Not only because the region has a huge resource of sunlight falling onto it, so tapping even a small proportion of that would be a cheap and clean way to provide energy for the country.
This is an excerpt from Tehran Looks to the Skies for Cheap Power from the Sun, which originally appeared in The Guardian. Alok Jha is a science and environment correspondent at The Guardian.
I am curious about water issues in this context. We are in a region of the world that is particularly lacking in fresh water resources.
According to NREL it is roughly similar to conventional steam plants, 2.8 m3/MWh. This depends of course upon the system utilized.
There are a few projects in the works that are utilizing CSP to concurrently engage in energy production and water desalination. Allowing surplus energy to be utilized for the latter purpose. This seems to be a region of the world, where similar strategies should be integrated, particularly if global warming exacerbates already limited fresh water supplies.
There is no reason why the water used in steam turbines can't be reused.
Anyway, I thought this technology was trending more to the use of molten halides (since the heat is more readily stored)