Singapore petroleum industry, started in the 1890s has expanded tremendously and made up to a significant 4.5 percent to Singapore's gross domestic product. Over the past 9 years, there has been an increase of petroleum refining capacity from 830 thousand barrels per day (kbd) in 1990 to 1344 kbd (62 % increase) (Figure 1), bringing Singapore to the top five export petroleum refining centers in the world .
As compared to the long-established petroleum, natural gas has also met the growing energy demand in Singapore. Singapore was ranked fifth among net gas-importing countries in Asia behind Japan, South Korea, India, and Taiwan with 341 billion cubic feet import and ahead of Thailand and China in 2009. As of the year 2008, almost 15% of Singapore primary energy demand and 75% of fuel demand for electricity generation is met by the natural gas alone. Over the next four years, the consumption of natural gas of Singapore is still expected to increase up to 448 billion cubic feet in 2014 (Figure 2).
Figure 2 Singapore Net Natural Gas Import 2009
Thus, it is evident that Singapore has started its growing reliance on natural gas as well as petroleum over the past few decades.
To effectively meet Singapore's long term needs, a diversified energy portfolio is needed which was a key recommendation by the Economic Strategies Committee .
Liquefied Natural Gas as an Energy Source
3.1 Risks
The first generic risk associated with natural gas application is safety concern due to its nature as an odorless, colorless, non-toxic and highly-flammable gas. Thus, its leak to the atmosphere might not be easily detected prior to become a source of ignition. However, this has been solved by the implementation of gas sensor in the gas-producing facilities and injection of odorant like t-butyl mercaptan and thiophane to the gas used in the household .
A major unique concern applies to natural gas usage in Singapore is the natural gas availability that depending on Malaysia and Indonesia through four trans-border pipelines up to 935 million standard cubic feet per day (MMscf/D); hence, exposing Singapore's energy security to uncertainty. Helen Cabulu concluded Singapore, having huge domestic gas consumption; from both household and industries without being sustained by its own domestic gas production as the most vulnerable country within the seven net gas-importing countries in Asia region(Figure 4). This makes Singapore prone to power outages due to gas supply disruption which has once strike Singapore back in June 2004 and 2006.
Figure 5 Gas supply security index of selected net gas-importing Asian countries
Departing from heavy dependence on neighboring states like Indonesia and Malaysia for supply and preventing future blackout, Singapore has started to construct the third LNG tank on Jurong Island topping up the expected capacity to 6 Million tonnes per annum (Mtpa). The fact that natural gas like other fossil fuel has no expiry date in storage, Singapore is allowed to not only meet its own demands but also seize the business opportunities within natural gas business with such a huge amount of storing capacity.
3.2 Advantages
For every ounce of risk taken, there is always a higher expected return comes with it. The advantages coming with the gas application both in house hold and industrial application are fewer harmful gas emissions and mitigation of smog and acid rain while contributing to better quality of air.
Table 1 Emission Levels of Various Fossil Fuels
Mainly comprise of methane, the natural gas produces water vapor and carbon dioxide which is straight-forward as compared to its counterparts, coal and oil. Having complex molecules composition, the two counterparts release not only high-level of CO2 but also other harmful chemical like NOx, and sulfur dioxide along with some ash particulates to the air. On the contrary, the combustion of natural gas generates minute amount of those air pollutants (Table1). Furthermore, its application in the power plant and industrial boilers replacing the coal reduce the amount of harmful sludge normally generated by scrubbing process of SO2 reduction.
3.3 Positive Impacts
Being a cleaner fossil fuel, the natural gas has played a significant role in decreasing the CO2 intensity and maintaining a relatively constant CO2 emission of Singapore at 39.9Mt regardless of increased burning of oil and coal since year 2004. Clinching the 0.17 kgCO2/2000 S$ in 2007 (significant drop of 30% from 1990, Figure 5) proves that Singapore effort in moving toward cleaner power generation has been fruitful with the gas high thermal efficiency and low CO2 emission.
Figure 6: Singapore Carbon Dioxide Emission from 1990 to 2007
Another impact is that natural gas grants energy scientists more time flexibility in exploring alternatives of renewable energy sources that is more affordable to Singaporean.
3.4 Disadvantages
All the goodness of the natural gas application in Singapore as an alternative energy source comes with a cost. The construction of terminals and managing such trans-border pipelines is not cheap, definitely. The cumulative investment on the Singapore LNG terminal project pumped in by the government to date is a strong $1.9 billion in purpose of reducing risks of gas supply security and outages. In spite of helping Singapore to diversify its energy source, the natural gas cannot be overly-relied upon. The fact that it is still a fossil fuel which cannot be renewed within reasonable timings, the total supply is finite; hence, over-reliance is undesirable.
3.4 Negative Impacts
The possible negative impacts for application of such a clean fuel of natural gas is complacency of finding an energy solution which may arise in people's mind; both Singapore government, scientists and the rest of civilization. Taking the natural gas for granted as a permanent replacement and solution of diminishing amount of oil is certainly undesirable. Regarding the main composition of natural gas; methane, few disputes have arisen as to whether the methane emission outweighs the benefits of reduced other harmful emissions, given its ability to trap heat which is 21 times more potent than CO2. A thorough study conducted by the Environmental Protection Agency (EPA) and Gas Technology Institute in 1997 has confirmed that total reduced emissions arising from increased natural gas application outweighs the detrimental effects of increased methane emission.
4. Future Outlook
4.1 Recommendation in the long run
Despite its environmental-friendly nature, the natural gas supply security of Singapore still relatively weak and vulnerable. On the flip side of coins, coal having abundant global supply contains too many harmful emissions to the atmosphere; hence, non-sustainable as well in the long-term. The approach to be taken by Singapore for long-run solution to this complex energy problems are not to get distracted by non-renewable energy sources like coal and LNG but to focus its effort more towards renewable ones.
Geographical location of Singapore might be excluding it from some possibilities like wind energy for power generation. Solar energy, thus far has been deemed to be the most promising source of many renewable energy sources. The Solar Capabilities Scheme (SCS), Clean Energy Research & Test-bedding Program (CERT), and $60million worth investment on Centre for Sustainable Energy Research (CSER) at Nanyang Technological University are some appropriate strategy implemented by the government to explore the diversified clean energy landscape of Singapore such as wind and marine renewables, energy storage, fuel cells, and green buildings.
Currently, the solar photovoltaic electricity generation is still not commercial yet and the efficiency with reference to the cost of solar thermal power stations does not seem attractive, as well. However, with the extensive support of government on relevant research projects, an affordable solar energy application could be expected. For the transition, the solar energy in its application may be combined with conventional coal-fired power station which is more well-known as Solar Aided Power Generation (SAPG). With improved efficiency and reduced green-house gases emission, this could be a better way of generating power coupled with the natural gas.
Meanwhile, as an individual residing in this beautiful land of Singapore, we should be aware with this energy issues and lend a helping hand to protect our mother earth in every way possible.
