Sunday, April 3, 2011

Technology : Nuclear over solar

Solar Power panel
THE Energy Commission (EC) chairman, Tan Sri Dr Ahmad Tajuddin Ali, said recently that nuclear power is preferred to solar power to help meet our rising energy demand.

The crux of his argument was, firstly, the cost of nuclear power is lower than the cost of solar power.

Secondly, according to Ahmad Tajuddin, "even if we cover the whole of Peninsular Malaysia with solar panels, it is still not enough" to fulfil energy demand.

House with Solar Power panel roofing
I will examine these two claims in reverse order. Firstly, a quick back-of-the-envelope calculation shows that the second claim is not true.

Solar panels convert sunlight directly to electricity. Taking the power input from the sun to be 200 watts per sq m (average data for Kuala Lumpur, source: Nasa), and assuming the conversion efficiency is 10 per cent, the power output of the solar panels, if they cover the whole of Peninsular Malaysia, is about two million megawatts (Mw).

Solar Energy Generator field
This power output is about 100 times the total power production capacity of 21,817Mw in 2009, where the maximum power demand was 14,245Mw (latest data available from EC).

Thus, in principle, we can meet our energy demand with solar panels alone, but this method is obviously not practical.

However, it is possible for solar power to contribute significantly to the total power production capacity.

For example, to produce 2,000Mw of power using solar panels, it would require 100 sq km of land, if 10 per cent efficiency is again assumed. A much smaller area would be needed if cutting-edge solar cells with efficiency of much greater than 10 per cent were used.

If Concentrated Solar Power (CSP) technology is used instead of solar panels, the land area required would also be significantly smaller for the same power output.

In the CSP method, sunlight is concentrated using a system of mirrors or lenses to produce heat to drive a turbine in order to generate electricity.

Secondly, the EC chairman's first claim about costs may be true now.

However, the cost of electricity produced using either solar panels or CSP is declining and is expected to be competitive with the cost of electricity produced using fossil fuels in the near future (source: Greenpeace).

Read more: Nuclear over solar http://www.nst.com.my/nst/articles/03lannay-2/Article#ixzz1IPUsOO1Q

No comments:

Post a Comment