Its low cost may make nuke energy an appealing choice, but there are challenges to making it available in Singapore
Leonard Lim, Straits Times 7 Feb 10;
From experts to the man in the street, all say it is a radical idea - nuclear power as an energy source for Singapore.
But while coffee shop talk is all stirred up over this wonder genie that is seen as both a boon and a bane, the official view is that nuclear energy is only a 'possibility' - and 'in the very distant future'.
Mr S. Iswaran, the Senior Minister of State for Trade and Industry, said last Wednesday that nuclear energy is 'not imminent', not even within the next five to 10 years.
But what is clear, in the recommendation by the Economic Strategies Committee (ESC), and in the Government's view, is that it is time to conduct feasibility studies.
For one, advances in technology are addressing some of the 'minus' issues like safety and spent fuel disposal.
Volatile and rising energy prices have meanwhile made the 'pluses' more attractive.
'We should go back to our fundamental strengths of forward planning and start to understand the issue,' said Mr Simon Tay, chairman of the Singapore Institute of International Affairs.
The ESC had said the country should consider nuclear power to generate electricity in the long term to reduce its reliance on oil and gas.
Fossil fuels like coal account for half of electricity production costs, said Assistant Professor T.S. Gopi Rethinaraj of the National University of Singapore's Lee Kuan Yew School of Public Policy.
'This is a big chunk. For nuclear energy, only about 3 per cent to 4 per cent of total production cost is due to the raw uranium,' he said.
'Even if uranium prices double, electricity prices will not be affected in a big way. But if coal, oil and natural gas prices double, it will greatly affect the electricity price.'
But perhaps the biggest issue is the public's safety concerns. Mention nuclear power and the 1986 Chernobyl disaster in Ukraine - then part of the former Soviet Union - comes to mind.
In that nuclear plant meltdown, there were 56 direct deaths while about 800,000 people suffered radiation exposure. It occurred after safety systems were inadvertently switched off when operators ran some tests.
Mr Tay, the former chairman of the National Environment Agency, said Singapore should look for emerging technologies that are safest and have the least negative impact on the environment.
One such technology could be pebble bed reactors, he said. These are fuelled by graphite spheres the size of billiard balls combined with small uranium cores.
The experts say these small cores, and the dispersal of the nuclear fuel among hundreds of thousands of spheres, help prevent a catastrophic meltdown in an accident.
Ms Sherie Ng, Invensys Process Systems' vice-president for strategy and marketing, said that technological advances and stringent requirements since Chernobyl have made nuclear energy a much safer option.
Invensys is a market leader in supplying safety systems to nuclear plants in countries like China and South Korea.
Automation and protective concrete, steel and alloy that are used to contain nuclear reactors and fuel, have reduced the risks of human error, or an accident.
'There's been no incident since Chernobyl, but you see accidents in industries like construction,' Ms Ng noted.
Meanwhile, an international safety recommendation is to have a 30km exclusion zone around a nuclear plant.
If adhered to here, there is virtually nowhere that a nuclear plant can be sited on the densely-populated mainland, which stretches about 40km from east to west.
But this rule is more for public reassurance than for technical reasons, said Prof Rethinaraj, who holds a PhD in nuclear engineering from the University of Illinois at Urbana- Champaign.
He added: 'This is mainly to deal with a worst-case scenario, so people can be easily evacuated.'
His own view is that a plant, when eventually built, could be located at the northern tip or one of the islands since there are practical difficulties finding a convenient site on the mainland.
But the Government will have its job cut out assuring the public on its safety aspects.
'Persuading the public to accept a nuclear power plant on the main island is a tough political question,' he said.
An alternative would be an underground nuclear plant, which may be the most feasible, he said. But this means higher initial costs, said energy analyst Dr Alvin Chew, though there are benefits.
One plus is the stable and solid rock formation in parts of Singapore which can serve as a shield during a disaster.
Dr Chew also wrote, in an S. Rajaratnam School of International Studies research paper last year, that a below-surface plant offers more protection against terrorist attacks.
Still, Prof Rethinaraj noted that the only underground nuclear reactors built are research facilities in places like France and the United States, not commercial ones.
An offshore facility is another option. In 2008, Minister Mentor Lee Kuan Yew indicated that the Government had thought about possible locations for a nuclear plant: on Pedra Branca, or on a floating platform out at sea.
But Prof Rethinaraj said the first location would be politically sensitive, given Pedra Branca's proximity to Malaysia, and the second would be a logistical nightmare.
'Singapore is a shipping centre. Having a floating platform with such heavy sea traffic carrying trade can create problems with managing security,' he said.
But whatever the current concerns, nuclear energy's appeal in the long term is its relatively lower cost.
It is the initial construction cost that is heaviest. Studies show that nuclear energy costs about US$2,000 (S$2,800) per kilowatt capacity, coal around US$1,200 and natural gas about US$500.
But nuclear energy has considerably cheaper generation costs, Ms Ng said.
It costs 1.87 US cents per kilowatt hour, while coal costs 2.47 US cents, natural gas 6.78 US cents, and oil 10.26 US cents.
Nuclear energy is also more environmentally friendly, she said, as the reactors emit less carbon emissions than fossil fuels.
But the other side of the coin is the spent fuel, which needs to be either disposed of or stored for around five years before being reprocessed and used again.
Singapore could consider storing the waste in an underground repository, but finding a suitable site would be a challenge, given its small size, Prof Rethinaraj said.
Striking an agreement with big countries like India or China, which manage large waste disposal programmes, is one solution.
All these are in the distant future, and only if, what will be very cautious, studies give the green light.
Mr Tay said: 'We need to scan the horizon, look at the technologies, and start the process of engagement and consultation with the public.
'I'm not sure we're ready to invest in a nuclear plant but let's start considering it, and watch the technology evolve.'
Other available sources
Straits Times 7 Feb 10;
Currently, about 80 per cent of Singapore's electricity is generated from natural gas piped from Indonesia and Malaysia.
Sources such as fuel oil, diesel and waste incineration make up the remainder.
Singapore is looking to diversify its energy sources but there are difficulties associated with other options, especially renewable energy.
SOLAR
With about 50 per cent more sunlight than temperate countries, Singapore is potentially a promising location for solar panels, or photovoltaic (PV) technology.
The Housing Board has test-bedded solar PV systems at estates like Serangoon North and Wellington Circle.
But high urban density makes deploying solar panels difficult, and the current technology cannot generate a significant proportion of Singapore's electricity even if all easily accessible rooftop and reservoir space is used. Cloud cover also reduces solar efficiency.
BIOFUELS
The Energy Market Authority is carrying out a study on the implementation of biofuels. One possible option is jatropha oil.
WIND
There may be opportunities to set up 'micro-turbines' about 3m to 10m in size on top of buildings, which can generate five to 50 kilowatts of power.
But an average wind speed above 5m per second (m/s) is needed to generate reasonably efficient power from wind turbines. The average wind speed here is lower than 3.3m/s.
Wind farms also require a large area.
WAVE AND TIDAL energy is restricted by Singapore's use of sea space for ports, anchorage and shipping lanes. Singapore's geography also does not present opportunities for HYDRO or GEOTHERMAL TECHNOLOGIES.
Sources: Energy Market Authority, Professor Subodh Mhaisalkar, co-director of the Energy Research Institute at Nanyang Technological University
Why a nuclear option is viable here
Sunday Times 14 Feb 10;
I refer to Mr Leonard Lim's 'Nuclear option' article last Sunday. Singapore's carbon footprint is reportedly 27.9 tonnes of CO2 (tCO2) per capita (or 15.2 tCO2 per capita, if marine bunkering is excluded).
Today, Singapore has more than 10,000 MW of generating capacity for electricity. Almost all of it is obtained from burning fossil fuels, producing large amounts of carbon dioxide daily.
The price of gas can fluctuate widely. Further, a 'carbon tax' is expected in future. Thus, Singapore should look into alternatives.
The nuclear option is a promising one. However, the general public is probably against nuclear power in Singapore, mainly because of the following concerns:
(1) Fears of Chernobyl-like nuclear accidents.
(2) Singapore is too small to house a nuclear power plant.
(3) Concerns over the handling and disposal of spent fuel and radioactive waste.
(4) The high capital cost of setting up a nuclear power plant.
I offer some brief answers regarding these concerns.
Concern No. 1: Modern nuclear plants developed in the West are very different from the Soviet era's graphite-moderated water-cooled reactors like those in Chernobyl. The so-called Generation III nuclear plants are safe.
Concern No. 2: Light water reactor power plants usually require a very large exclusion zone of more than 10km. However, the high- temperature gas-cooled reactors HTR-PM that China is building in Shangdong each requires a very small exclusion zone because the reactor is passively safe and the fission products are distributed among billions of sub-millimetre- sized containment shells.
Concern No. 3: Spent fuel bundles from conventional reactors require special cooling and monitoring and there are proliferation concerns with the spent fuel. Eventual disposal of these fuel bundles can be contracted out for reprocessing in countries like France, Japan or even China. However, spent pebbles from HTR require very little maintenance or monitoring because the contents in each pebble have only a few grams of heavy metals and fission products distributed among tens of thousands of tiny containers which are protected by the graphite matrix.
Concern No. 4: A nuclear power plant capital cost is usually high compared with other power plants. But in terms of cents per kWh, nuclear power is cheaper than other power sources. This is particularly true if a carbon credit is taken into account. However, the real benefit of nuclear power is its displacement of fossil-fired power and a great reduction in greenhouse gas emission.
Phil Choong
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