Wednesday, March 23, 2011

Drop nuclear, go solar

Mar 24, 2011

SENIOR Minister Goh Chok Tong attributes our present water self-sufficiency to political will, sheer determination and creativity ('Clean water a result of a wave of effort'; Monday).
It is now time to focus on garnering new energy resources.

In the same way that our neighbours cannot be depended upon to sell us water in perpetuity, neither can we assume that, in the future, Singapore will not be deprived of oil and gas. Our search and development of alternative sources of energy must start now and should have no less the intensity and ingenuity we levied on water.

After the recent Japanese disaster, nuclear power is clearly not the answer. The world has about 400 nuclear power stations and already we have had a few major incidents.

[The 3 that comes to mind are Three Mile Island, Chernobyl, and now Fukushima. 3 out of 400].

The chances of having a disaster if Singapore operated a nuclear power generator for 100 years are high, a consequence we, on our postage stamp-size country, just cannot live with.

[How do you decide that 3 out of 400 is high?]

Even with research on solar power in its infancy, with vast improvements in costs and efficiencies certain in the future, a back-of-the-envelope calculation shows that, should all HDB blocks be installed with solar panels on the roof, 20 per cent of our present energy needs can be met. The potential seems unlimited.

[You just said, the potential is limited to 20%. Also, what is the costs? The back of your envelope needs to be bigger to have more details. The current tech is not promising. Take a look at this real project:

This is based on Concentrated Solar Power (CSP) which is currently the most efficient solar power generator. To generate 100 MW, it will cover 741 acres or about 2.5 sq km. Singapore needs about 5000 MW on average. To supply 20% of our electricity needs (or about 1000 MW) we will need to have 10 of these CSP or about 25 sq km. That's my calculation. Let me double check that with Wikipedia.

Wikipedia suggest 6000 acres or 24 sq km for a CSP generating 1000 MW, and if using photovoltaic (PV) solar cells, 12,000 acres or 48 sq km for the same output. And this is just to generate 20% of our CURRENT electricity needs.

The idea is to put this on HDB roof tops? CSP is out for roof tops, so we'll check PV. 48 sq km = 48,000,000 sq m. There are about 10,000 HDB blocks, so that's 4,800 sq m of roof required per HDB block.

NO HDB block has a roof that big. That would mean about 48 4-rm flats per floor.

Even if you double the efficiency of the PV, that would still mean 2,400 sqm of roof. Assuming all blocks have about 800 sqm of roof, PV technology needs to be at least 6 times more efficient.

So really? PV the roofs of HDB flats and provide 20% of energy needs? Bullshit!]

The science behind solar panels involves semiconductor technology, which Singapore already excels in. It is well within our ability to research and manufacture these panels. The market for them already exceeds $30 billion, and getting a slice of this action will open up a whole new sector of manufacturing for Singapore.

Solar energy is clean and green, dependent on an ample resource, free of encumbrances imposed by neighbours and is difficult to sabotage.

[And you forgot expensive, inefficient, and unlikely to ever be a major source of energy in land scarce Singapore. At best it will supplement our energy requirements, but it will be a minor component. Unlikely to ever hit 20% of our energy needs.]

There is far more for Singapore to gain by embracing solar power over nuclear energy.

Dr Yik Keng Yeong

[The most promising solar power that can generate the kind of concentrated power required for a highly urbanised city like Singapore, is going to be CSP. The downside is that it will need a large contiguous area to operate. None of that solar panel on every HDB block shit. So the land requirement basically renders that idea unfeasible.

PV and other technologies yet to be invented or improved are expensive and inefficient, and at the current development, will not be able to be implemented in the next 5 to 10 years.

The more immediately implementable ideas are safer nuclear power. But we don't need them at this point, and we don't need to make a decision yet. However, dismissing them out of hand and out of fear and out of a philosophical or ideological position is neither constructive, nor instructive.]

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