Singapore to Zero (Part 2: Context)

Before we examine the challenges and opportunities for Singapore, it is worth understanding what Singapore’s energy system is like today. In Part 2, I provide a high level overview of Singapore’s energy system which is an essential starting point for any discussion on energy transition.

This is what we will cover in Part 2:

Diagram notes:

1. The above diagram has been prepared by me in an attempt to capture the high-level supply and demand flows through Singapore.
2. The figures have been compiled and summarized based on data from the Energy Market Authority and the Maritime and Port Authority of Singapore. The figures are approximate of the values as at 2019.
3. The figures have been rounded off to represent the order of magnitude for a high level overview, and is not intended to be exact.
4. The figures in grey are energy quantities measured in ktoe (kilo metric tons of oil equivalent), which literally means the energy value contained in 1,000 metric tons of oil, which is equal to around 41.9 Terajoules based on EMA data tables. I qualify this since even ktoe may have slightly different conversion factors since oil isn’t a homogenous commodity. Converting between energy units can be confusing even for experts, so we’ll stick to ktoe for this discussion.
5. The figures in red are calculated based on the approximate carbon intensity (tons of CO₂ per ton of fuel) derived from the carbon content in each fuel type, and which works out to around Oil = 3.14; Natural Gas = 2.31 and Coal = 4.74
6. The figures show the net energy quantities consumed in Singapore and excludes volumes being imported and exported. In particular, it is worth noting that Singapore has a trading throughput of around 90,000 ktoe of crude oil and petroleum products, and this is not reflected in the diagram.
7. The figures are also the primary energy consumption, i.e. the amount of the raw form of fuel used, which ultimately determines the CO₂ we emit. Therefore, electricity, which is a converted form of energy is not reflected in energy units but in percentages % to give an overview of the distribution of how our electricity is consumed.

Overview

1. Overall, Singapore consumed 70,000 ktoe of primary energy.
2. Bunkering: 50,000 ktoe. In general, bunkering (the supplying of ship fuel) results in fuel combusted outside of Singapore’s boundary, so it does not contribute to total CO₂ emissions within Singapore’s boundary.
3. Domestic consumption: 20,000 ktoe. Consumption of these fuels results in Singapore’s assessed CO₂ emissions.
4. Almost all energy consumed is imported. Singapore’s electricity generation also includes domestically derived energy including municipal waste, biomass and solar PV (~700 ktoe)
5. Based on my calculations, Singapore emits around 55 million metric tons of CO₂ per year.

Supply: Natural Gas

Natural gas is key energy supply. As many Singaporeans know, natural gas is our main energy supply. We consume just over 10,000 ktoe each year, primarily for electricity generation (9,000) and the balance is consumed by industry.

Natural gas import

• 65% by pipelines. Pipelines connect Singapore to regional gas supply, primarily from Indonesia, and the supply has been declining from a peak of around 8,000 ktoe in 2013 to around 6,600 in 2019.
• 35% by LNG. Liquefied Natural Gas (LNG) connects Singapore with global gas supply from Australia, the USA, Africa and some from South America and the Middle East. Imports started in 2013, with around 1,000 ktoe, and increased to around 3,600 in 2019.

Strategic positioning. Importing natural gas by LNG is good strategic positioning by Singapore. This example is an important one we will keep in mind. Importing energy via ships allows Singapore to connect to global supply and this will be key to the energy transition to low- and zero-carbon energy supply as well, as we will discuss in subsequent parts.

Supply: Oil

Excluding oil consumed in bunkering operations, Singapore consumes around 8,700 ktoe of oil, 6,500 of which is consumed by industry and 2,200 in the ground transportation sector.

Supply: Coal

Singapore consumes some coal, around 450 ktoe, with 200 into industry and 250 into electricity. These figures fluctuate quite a bit from year to year though.

Among hydrocarbon fuels, coal has the highest carbon intensity. In addition it contains other impurities that results in other pollutants and effluent that has to be managed. So it is good that it represents only a small fraction of our energy supply.

Demand: Bunkering

Singaporeans all grew up studying how Singapore’s history as a trading port made it a thriving settlement. True to this day, Singapore’s port activities continue to be highly relevant to its economy from the importing of required resources to enabling industries that rely on re-exporting of value added products.

Singapore is also the largest bunkering port in the world, supplying almost 20% of the global ship fuel demand.

Based on statistics published by MPA, Singapore’s bunkering volume averages around 50,000 ktoe per year over the last 5 years.

As such, the Port of Singapore has a global leadership role in setting standards around bunkering such as mass flow metering.

Aligned with the global vision to net-zero and standards set by the International Maritime Organization (IMO), the Port of Singapore is also playing a critical role in piloting the bunkering of cleaner alternative fuels, which we shall discuss more.

Demand: Industry

Singapore’s industrial sector is a key economic pillar contributing over 20% GDP.

Since 2014, the industrial sector directly consumed around 8,000-8,500 ktoe per year, comprising around 6,500 from oil, 1,300 from natural gas and balance ~200 from coal.

Additionally, it consumed around 21,500 GWh of electricity (or about 42% of Singapore’s electricity demand), indirectly consuming a similar proportion of the primary energy consumed to produce electricity.

On the use of coal, Keppel Infrastructure had announced in 2017 that it would be constructing a gasification facility that could use coal, but also other feedstock like refinery by-products, to produce useful feedstock, primarily hydrogen, but also carbon monoxide. Since then, not much has been announced regarding how much CO₂ emissions the facility would emit, or the development progress of this facility.

This seems to run counter to Singapore’s national strategy to use lower carbon intensity energy sources such as natural gas. But of course, as with all energy options, it must be considered from a holistic perspective. One cannot just consider emissions, but also the economic aspect. Singapore has always sought to strike a balance between environment and business opportunities.

However, a lot has changed in the zero-carbon energy scene since 2017, and there are now opportunities for low- and zero-carbon hydrogen feedstock and we shall discuss.

Secondary Supply: Electricity Generation

Electricity generation is by itself not an end use, but converts primary energy sources into electricity for downstream applications and segments.

Around 95% electricity is generated by natural gas, increasingly with high efficiency combined cycle gas turbine (CCGT) technology.

Around 9,800 ktoe of energy input generates almost 52,000 GWh of electrical energy (net of transformation losses), with an average generation efficiency of around 47.5% and net of transformation efficiency of 45.6%.

Peak power demand 7,400MW.

Peak power generation capacity is around 12,500MW. So, Singapore’s generation-to-demand coverage is around 1.7x. More importantly, around 10,500 MW of generation capacity is natural gas-fired gas turbines with good load matching capabilities, ensuring that Singapore has a stable electricity grid.

Singapore’s grid carbon intensity is around 400g/kWh, which corresponds to a predominantly gas-fired CCGT electricity grid.

Since Singapore is already using the cleanest fossil fuel, natural gas, reducing the carbon-intensity of power will have to rely on low- and zero-carbon options.

Solar PV Potential

Currently, Singapore around 400 MWp installed as at 2020, and is on track to 2 GWp installation by 2030. But how much can Singapore generate from domestic solar resources?

Source: The above screenshots are from Global Solar Atlas.

Contrary to layman impression that we live in a sunny country and have good solar PV generation potential, the high humidity and frequent cloud cover and rains imply that our specific PV power generation is around 1,280kWh/kWp (almost 40% lower than the 1,900 – 2,100 in other regions such as Australia and the Middle East).

Current target: Singapore is targeting to install 2GWp of solar PV by 2030.

Output. This means that 2GWp installed capacity would translate to 2,560 GWh, or just about 5% of our current 52,000 GWh electricity demand.

Optimal Angle. The optimal angle to produce the maximum power output is to install the panels in Singapore at an angle of 2 deg towards the equator. So if we considered installing PV panels on the vertical facades of buildings, the specific PV power output would not be optimal.

Grid firming. While intermittent solar power is not going to be a problem for Singapore’s grid at 5% level, we would need to consider grid firming strategies as we increase our solar capacity. Currently, natural gas-fired turbines play this role well, but if we are to transition our energy system, we would need low- and zero-carbon firming options such as grid storage or gas turbines running on low- and zero-carbon fuels.

Potential. According to the 2020 Updated Solar PV Roadmap for Singapore report, Singapore’s assessed economically viable PV-installation areas would translate to a potential of 8.6 GWp. This assumes some degree of panel efficiency improvements going forward to an average of 0.23 kWp/m2. Also, slightly more than 25% of this capacity includes installation on building facades which have a threshold irradiation of around half that of installation on a horizontal surface. Considering the above, the 8.6 GWp would deliver around 10,000 GWh of electrical energy per year. This would be 20% of current electricity demand, or say 12-15% assuming our electrical demand expands by 50% or so going forward.

Carbon mitigation effect. With a grid carbon intensity of around 400g/kWh, 10,000 GWh of PV-generated electricity has the potential to reduce CO₂ emissions by around 4 million metric tons per year, or about 6.2% of our expected peak emissions of 65 million metric tons per year by 2030.

Comments. Singapore should certainly be exploiting all its available renewable power potential that is economically feasible and can be reasonably integrated into the grid without causing grid stability issues – it should be noted that solar is intermittent with low availability, and cannot be considered with the same reliability as other forms of on-demand generation.

Solar PV capacity is a function of availability of land area and quality of the solar irradiation and Singapore is challenged on both fronts. The maximum potential of 12-15% of our electricity demand and a maximum potential to reduce CO₂ emissions by 6% from 2030 peak implies that we will need to innovate other low- and zero-carbon energy solutions to get to zero.

Electricity – General

For the Commercial and Residential segments, over 90% of energy consumed is in the form of electricity. And the remaining comprises natural gas and petroleum products (typically LPG for heating/cooking).

Only around 6% is consumed by the transportation segment (which in my guess is primarily to operate the mass rapid transit (MRT) trains in Singapore).

Data Centres (DC)

As at 2015, around 50% of Southeast Asia region’s DC capacity is located in Singapore, and which accounts for at least 9% of Singapore’s electricity demand.

Demand for DC capacity is surging with demand for cloud computing, storage and AI. With the pandemic accelerating online-based working, learning, communication, entertainment and gaming, data center capacity is bound to grow rapidly from here.

In “The Arcadis Data Center Location Index 2021” report, Singapore is ranked 2nd among 50 countries, scoring well in most attributes except for a relatively low score on energy security.

However, given the energy intensive nature of data centres, there has been a moratorium of new data centre projects since 2019. This puts Singapore at a disadvantage if its moratorium on new data centres continues. Unfortunately, from a practical point of view, Singapore has to control the expansion of data centre capacity to balance electricity demand growth and the stability of the electric grid – here is where energy supply limits opportunities for economic growth.

Acknowledging this challenge, Singapore is currently aggressively innovating on ways to make data centres more efficient, particularly on how to more efficiently address cooling loads, which can be up to 50% of a data center’s power consumption.

Another solution pathway would be to bring about availability of low- and zero-carbon power generation at large-scale to Singapore. In fact, solving the supply side naturally unlocks this and other energy-dependent opportunities.

Electrification of Transportation

In 2020, Singapore announced plans to phase out petrol and diesel vehicles by 2040 and replace it with electric vehicles (EV).

Reduction in local emissions. While there is no emissions at the tail-pipe, it will simply be transferred upstream to emissions at the power plant. However, since Singapore’s electricity grid is primarily gas-based, this would still result in a net reduction in emissions in Singapore’s boundaries.

• Assuming 100% conversion of current transport to EVs, and further assuming that the fuel-to-wheels efficiency of an EV is a rule-of-thumb double that of the internal combustion engine vehicle, this would add around 6,000 GWh, or 11.5% increase relative to our current electricity demand of 52,000 GWh.
• CO₂ emissions could reduce by around 4.4 mil metric tons per year based on the current carbon intensity of Singapore’s grid. The reduction could increase to over 7 mil metric tons per year if low- and zero-carbon electricity generation options are available.

Lifecycle considerations. A true lifecycle comparison of an internal combustion engine vehicle (ICEV) and a battery electric vehicle (BEV) would entail analysis of the production, use and end-of-life pathways of the chassis, power train and the batteries. To simplify this discussion, I am only doing a high-level comparison battery production which would be the biggest difference between an ICEV and a BEV.

Battery production is an energy intensive process. Much of today’s battery production is produced using energy from fossil-based sources and the GHG impact varies widely depending upon the actual supply chain’s energy mix.

Source: Kelly, J.C., Dai, Q. & Wang, M. Globally regional life cycle analysis of automotive lithium-ion nickel manganese cobalt batteries. Mitig Adapt Strateg Glob Change 25, 371–396 (2020).

The figure above shows that battery lifecycle emissions ranges from 40-140 kg.CO₂e/kWh, with the dominant supply chain at around 100.

Singapore has about 1 million vehicles, and assuming an average 60kWh battery capacity (across all vehicle types motorcycles, passenger, buses, trucks) and 10 year useful lifespan, 100% electrification by BEV would require 1 mil x 60 / 10 = 6 mil kWh per year, or additional upstream 0.6 million metric ton CO₂e/year assuming the dominant supply chain (but this can also be decarbonized eventually). On a lifecycle basis, this additional upstream emissions partially offsets the emissions reduction domestically.

Electrification by fuel cell. BEVs are great for light-duty and other low-usage vehicles, but they are not optimal for heavy-duty applications where turnaround time, payload and driving range are critical. For these, fuel cell electric vehicles (FCEVs) are more suited.

As at 2020, Singapore’s vehicle fleet include 70,000 private hire vehicles, 16,000 taxis, 19,000 buses and 44,000 heavy and very heavy goods vehicles. These are categories in which the fuel-cell electric powertrain is preferable to the battery electric powertrain.

The question of course is the supply chain for hydrogen, which supply isn’t quite as ready as retrofitting the electric grid with charging points. However, I address this in the final part.

CO₂ Emissions

Now we see how all the above energy use translates into Singapore’s emissions footprint. The chart below is for 2017, and published by the PMO’s National Climate Change Secretariat.

Conclusion

Part 2 sets a high-level understanding of Singapore’s energy system. Energy is the lifeblood of any economy and it is true for Singapore as well. Singapore is an energy importing country, and so its economy naturally depends on being able to secure energy from regional and global supply. However, we now have a third dimension of emissions and the environment. The intertwined nature of energy, economy and the environment is the new challenge humanity has to grapple with going forward.

In Part 3, we shall discuss a framework for how Singapore can evaluate options for transition of its energy system.