Thinking small for Singapore nuclear needs

Michael Richardson, for the Straits Times 26 Apr 10;

OFFICIALS from different agencies led by the Ministry of Trade and Industry will begin a study later this year into the feasibility of nuclear power for Singapore. The questions they will consider include whether future costs and technology advances could make nuclear generation systems more suitable for countries like Singapore with relatively small land space and electricity grids.

The answers to both questions appear promising. A recent survey of fossil fuel and low-carbon electricity generating plants found that when financing costs are low, as they are in Singapore, nuclear energy is the most competitive.

The survey, published last month by the International Energy Agency and the Organisation for Economic Cooperation and Development's (OECD) Nuclear Energy Agency, drew data from nearly 200 power plants in 21 countries. It used a standardised measure of the cost of electricity per megawatt hour (MWh) over the lifetime of a plant and assumed that there would be a carbon price of US$30 (S$41) per tonne imposed by governments to discourage carbon emissions.

The survey provided results for two interest rate levels: 5 per cent and 10 per cent. A lower borrowing cost favours nuclear because it is far more expensive to build the current generation of big power reactors than coal or gas-fired plants.

Singapore relies on gas. At the 5 per cent rate, the lifetime costs of power from gas-fired plants in OECD countries vary from US$67 per MWh for Australia, which can draw on cheap local gas, to US$105 per MWh for Italy, which like Singapore must import gas. At a 10 per cent interest rate, the costs range from US$76 per MWh (Australia) to US$120 (Italy).

At a 5 per cent rate, costs for nuclear electricity generation in OECD states vary from US$29 per MWh for South Korea to US$82 for Hungary. At a 10 per cent rate, the range is from US$42 per MWh (South Korea) to US$137 (Switzerland). These figures include costs of radioactive waste treatment and decommissioning after a 60-year lifetime.

Comparable costs for coal-fired plants at a 5 per cent interest range from US$54 per MWh (Australia) to US$120 (Slovak Republic). This is both with and without storing the carbon dioxide they release. At a 10 per cent rate, the costs vary from US$67 (Australia) to $142 (Slovak Republic).

A typical 1,000MW nuclear plant in Asia today costs between US$3 billion and US$5 billion to build. But this high upfront capital investment is expected to fall sharply as a series of smaller, safer and easier-to-operate reactors come into service over the next 20 years.

There are at least 15 different small reactors, ranging from around 30MW to 300MW in an advanced stage of development in the United States, Russia, Japan, China, South Korea, South Africa and Argentina, according to the World Nuclear Association.

Many are designed to run underground and to suit operating conditions in small states by conforming to the general rule that no single power reactor should be larger than 15 per cent of national grid capacity, which in Singapore's case is around 6,000MW at present.

The International Atomic Energy Agency has estimated global demand for small reactors could reach 500 to 1,000 units by 2040 as more cities, towns, industries and remote locations seek their own sources of reliable low-carbon power. This may create new regulatory and proliferation challenges but would help cut global warming emissions.

Another feature of small reactors is relevant to Singapore. Many are modular and can be scaled up as power demand and the size of the national grid increase.

The US Nuclear Regulatory Commission is preparing to start the process of approving the first of seven small reactor designs from October this year.

Meanwhile, the US Energy Department announced last month that it was awarding US$40 million to two international groups to finish their conceptual designs and plans for next-generation reactors by August.

Both groups are proposing to build small reactors cooled by helium gas, which reaches high temperatures of about 850 deg C. The heat can be used not just to drive steam turbines to generate electricity but also for industrial and district heating.

US Energy Secretary Steven Chu has described small modular reactors as 'one of the most promising areas' in the nuclear industry. Although somewhat more expensive per kilowatt of power, they will be much easier to finance than big reactors that take far longer to build.

A new small reactor could be installed within three years to start generating income from sale of electricity and heat to pay for the next and subsequent modules as needed.

A combination of improved safety and lower capital investment costs may help remove two of the main barriers to the spread of nuclear power generation.

For Singapore, this may turn out to be a case of small is beautiful.

The writer is a visiting senior research fellow at the Institute of Southeast Asian Studies.