Concentrating Solar Power (or CSP) is inefficient, expensive, and has notable environmental impacts.

Inefficient
According to the California Energy Commission ( http://www.energy.ca.gov/electricity/gross_system_power.html ), all of the utility-generated solar power in the state amounts to two-tenths of one percent of the state’s electricity production. Because of the limited availability of sunlight, these systems have notoriously low capacity factors and therefore cannot be relied upon for baseload power.

Expensive
According to the California Energy Commission ( http://www.energy.ca.gov/electricity/comparative_costs.html ), at 13 to 42 cents per kWhr, solar power is *the* most expensive way to generate electricity. In a time when energy prices are skyrocketing, few people can afford a large-scale conversion to solar power. What’s more, due to its low capacity factors, solar capacity must be backed up with additional stand-by power generation, which adds to the overall cost of solar.

Environmental impact
Solar collectors also require a huge area of land, which must be dedicated to solar generation. Even in the desert, this could disrupt the delicate ecology. Additionally, in order for the salts to remain molten at night, CSP requires fossil fuels to be burned for heat. According to a US Department of Energy study ( http://www.nrel.gov/docs/gen/fy98/24496.pdf ), these systems are “hybridized” with up to 25% natural gas. Ironically, this renewable technology is a contributor to greenhouse gas emissions!

Nevertheless, concentrating solar technology, along with many other renewable power sources such as wind, tidal, and geothermal, should continue to be supported in hopes that a breakthrough will someday allow them to be a significant source of energy generation. Today however, CSP is no replacement for baseload energy generation sources. In the medium term, we cannot abandon the proven, effective, and efficient source of low-emission energy that nuclear power has to offer. To learn more about the benefits of nuclear energy, check out http://www.nei.org/index.asp?catnum=1&catid=11 and http://www.casenergy.org/WhyNuclear/TheBasics/tabid/66/Default.aspx

Michael Stuart

There really is no need for nuclear power in South Africa since there is a simple mature technology that can deliver huge amounts of clean energy without any of the headaches of nuclear power.

‘Concentrating solar power’ (CSP), employs the technique of concentrating sunlight using mirrors to create heat, and then using the heat to raise steam and drive turbines and generators, just like a conventional power station. It is possible to store solar heat in melted salts so that electricity generation may continue through the night or on cloudy days. This technology has been generating electricity successfully in California since 1985 and currently provides power for about 100,000 Californian homes. CSP plants are now being planned or built in many parts of the world.

CSP works best in hot deserts and it is feasible and economic to transmit solar electricity over very long distances using highly-efficient ‘HVDC’ transmission lines. With transmission losses at about 3% per 1000 km, solar electricity may be transmitted to anywhere in Namibia. A portion of the Namib desert would be sufficient to meet all of Namibia’s needs, and South Africa’s as well.

In the ‘TRANS-CSP’ report commissioned by the German government, it is estimated that CSP electricity, imported from North Africa and the Middle East, could become one of the cheapest sources of electricity in Europe, including the cost of transmission. A large-scale HVDC transmission grid has also been proposed by Airtricity as a means of optimising the use of wind power throughout Europe.

Further information about CSP may be found at http://www.trecers.net and http://www.trec-uk.org.uk . Copies of the TRANS-CSP report may be downloaded from http://www.trec-uk.org.uk/reports.htm . The many problems associated with nuclear power are summarised at http://www.mng.org.uk/green_house/no_nukes.htm .

The aspects of the report that deal with the security of radioactive material are more reasonable, but the conclusion should be that we need better and more effective anti-proliferation techniques and agreements and better security, not that we need to abandon nuclear power. After all, it’s not like there’s a choice here between nuclear power and solar/wind/wave power; since the latter options can’t deliver the base load power that’s required. Thus the choice is really between nuclear power and yet more coal and oil fired plants. With global warming being the issue that it is, do you really think we should be building more coal and oil plants?