Tag Archives: coal

Decarbonising Singapore’s power sector

Singapore’s power sector is responsible for about 40% of the total emissions of Singapore (NCCS, 2022) and in 2024, almost 95% of the power produced in Singapore was generated using Natural gas (EMA, 2025). I estimated that we consume about 300 PJ of natural gas just for power production alone, assuming that gas power generation on average is at about 60% efficiency. And from that same dataset you’d also realise we have 0.9% of coal-fired power in the mix.

The recent EMA announcement about the 300MW biomethane pilot for power plants (EMA, 2025) implies a 3% reduction in fossil natural gas use, replaced by biogenic carbon dioxide from the combustion of biomethane, which is not considered a greenhouse gas (GHG) emission. Assuming this quota and capacity is used in full, it should lead to about 740 ktCO2e of GHG emissions abated.

Another news was about Tuas Power replacing all of its coal with biomass for power generation by 2028 (Tuas Power, 2025). This implies that the 0.9% of coal contributes to the fuel mix will no longer be emitting carbon dioxide. I did some back of envelope calculation on the emissions from the coal power generation and estimated it to be at around 300tCO2e per annum only. This is likely because the plant’s capacity factor isn’t very high. If the 133 MW capacity was firing in full all the time, they should be emitting around 700tCO2e.

Now if we follow the 2022 emission profile figures, the power sector is responsible for about 21MtCO2e of emissions from Singapore. Those reductions of about 0.75MtCO2e of emissions seem relatively insignificant. Indeed, it looks like only 3.5% of the total emissions will be reduced in the grand scheme of things.

Sure, we are going to import more renewable energy and as a proportion of total power generated, we will increase the percentage figure. The grid emissions factor will probably decrease especially since we are going to have more MWh of green electricity. But for the existing power generation capacity to decarbonise in the short term, biomass and biomethane remain the more readily available solution. Those pilots and announcements may herald the beginning of greater ambitions.

Gas Transition

Natural gas seem to be the fossil fuel which was supposed to be a transition fuel that overstayed its welcome. In fact, it seem to have failed at its job at properly displacing coal and yet today, it is seen as a dirty fuel to be transited away from rather than towards.

That is actually a very anglo-saxon view of the energy transition and if you go around Asia, to some of the fast growing economies you’d realise that notion is somewhat deluded. Natural gas is still growing and providing more energy to more businesses, households and people not because of the gas lobby or some kind of oil & gas conspiracy but that plans laid down in the past to move towards gas are just cranking on and moving forward. Sure, things are not moving as fast as we would like them to, but it is incredibly challenging to keep trying to drive people off gas towards renewable electricity when we have not properly dealt with or created a realistic pathway out of coal power.

A premature transition out of gas, especially for currently non-electrified uses, could be expensive. And electrifying heavy industrial loads when a power system is still dominated by coal, is certainly emissions-blind.

Making the transition II

Transition means being in an in-between state, crossing over to something which is supposed to be perhaps a less temporary state. The challenge, however, is that one can get stuck in transit. Natural gas as a fuel risk being in that state because it wasn’t really adopted fast enough as a transition fuel. And now renewable electricity from solar and wind has more or less leapfrog it in terms of cost advantage. Once battery or other energy storage technology moves along the cost curve and decline sufficiently, natural gas might even be bypassed.

So the world is in a somewhat confused state. When is it right to use gas? What should be counted as alternatives for decarbonisation? In any case, gas prices are spiking now so what does it mean? Should that mean we move forward into more renewables which might even be more expensive? Or we move backward into coal?

These decisions are not meant to be made in categorically; because the entire system needs to be considered. And what is at the margin in terms of choice needs to be clearly identified. If the additional unit of power that satisfies both energy security and the quantity demanded can be obtained through renewables, it should be used. Of course if that is not available, one might have to step back into more carbon-intensive processes. Availability can also be based on budget.

Natural gas itself, needs to be displaced by greener fuels without threatening the underlying combustion technologies that underpin the gas turbines. But that is perhaps for another day.