What could Singapore’s energy mix look like in 2035?

About 40 per cent of Singapore’s greenhouse gas emissions now come from the power sector, so if the Republic is to reach its ambitious target of being net zero by 2050, a lot of its effort must go to greening this sector.

By 2035, natural gas will still make up more than 50 per cent of the country’s energy mix, though much less than now, with imports of renewable energy accounting for about 30 per cent.

Which are the energy sources that could form the remainder of Singapore’s future fuel mix, and what are the key changes needed to decarbonise the energy sector?

Here’s a look at what could happen.

Currently, almost all of Singapore’s energy is generated from natural gas:
 

As at June 2023, 94.3 per cent of the fuel mix came from natural gas. Singapore’s liquefied natural gas (LNG) plant consists of one 260,000 m³ storage tank, three 18,000 m³ storage tanks, and two jetties that can fit vessels from 2000 m³ to 265,000 m³.

According to Mr Chong Zhi Xin, the director of gas, power and climate solutions at S&P Global Commodity Insights, slightly more than 40 per cent of Singapore’s total gas supply is LNG, carried here on ships from countries such as Australia, Qatar, and the United States.

The remaining 60 per cent is natural gas piped from Indonesia and Malaysia.

About 4.4 per cent of Singapore’s energy comes from other sources, such as solar and municipal energy waste.
 

Singapore has at its disposal more than 1 gigawatt-peak (GWp) of solar power, which would take about five million square metres of solar photovoltaic cells to produce, said Professor Chan Siew Hwa, who is co-director of the Energy Research Institute at the Nanyang Technological University (NTU).

It also has four waste-to-energy plants, which incinerate all the nation’s waste and produce electricity in the process.

Some 0.9 per cent of the energy mix comes from coal. Singapore’s only coal-burning plant, the Tembusu Multi-Utilities Complex on Jurong Island, supplies steam and electricity to chemical companies on the industrial island.

Finally, 0.3 per cent of power for Singapore comes from petroleum products, such as oil.

By 2035, Singapore aims to reduce reliance on natural gas, which will make up more than 50 per cent of the energy mix, paving the way for other sources of renewable energy.

Natural gas is projected to be reduced from the current 94.3 per cent to more than 50 per cent. Some 30 per cent is expected to come from renewable energy imports.

By 2035, import deals signed with Vietnam, Cambodia and Indonesia are expected to be in force. The final 20 per cent could include solar, various forms of hydrogen, biofuels, nuclear power, and geothermal power.

For the more than 50 per cent of the energy mix that will still come from natural gas, a larger share is likely to come from LNG imports, as existing piped gas contracts expire. For instance, contracts with Indonesia to import piped gas will expire in 2023 and 2024.

For the 30 per cent from renewable energy imports, the deals signed so far for which the Energy Market Authority (EMA) has given conditional approval are:

• 2 gigawatts (GW) of low-carbon electricity from Indonesia, predominantly solar;
• 1 GW of solar, hydropower and potentially wind from Cambodia;
• 1.2 GW of primarily wind energy from Vietnam.

There could be more, as EMA has received more than 20 other proposals for low-energy imports since it started soliciting applications in 2021.

One proposal is for the import of 1 GW of hydropower from Sarawak by a consortium comprising Sarawak Energy, Sembcorp Utilities, and Singapore Power International.

EMA, citing commercial sensitivities, would only say it is in discussions with companies that have submitted proposals.

While some experts expect Singapore to go beyond its current target of 4 GWp for renewables by 2035, others say that renewable energy is still costly to produce at scale, which prevents the Republic from importing a larger share of it.
 

Mr Melvin Chen, Wood MacKenzie’s vice-president and head of power and renewables consulting for APAC, said imports are expensive because suppliers need to provide consumers with a stable supply of electricity when renewables like wind and solar are intermittent, being weather-dependent.

This necessitates building much larger plants coupled with expensive battery storage solutions, he added.

In addition, expensive subsea cables are needed to transmit electricity from regional countries to Singapore.

“The pace of more renewable imports will really depend on the success of the current-approved projects, but will have to be balanced with energy security needs, to avoid being overly dependent on power imports,” said Mr Chen.

What will make up the remaining 20 per cent or so of the total energy mix?

It remains to be seen how much of a role the other forms of clean energy will play.
 

Importing green hydrogen via a pipeline

As Singapore has limited renewable energy capacity, it would be more viable to import green hydrogen produced in other countries. By 2035, some small-scale trials using imported green hydrogen could be in place.

Mr Chen noted that green hydrogen production technology is still in its infancy, and is not yet commercially viable.

This is partly because the electrolysers are expensive to produce, and not yet at large scale, keeping costs high.

The price of solar and wind energy would also have to come down further, in order to make it more cost-effective to use these renewable sources to help produce green hydrogen.

But there may be things that can be done to bring costs down. For instance, existing pipelines now used to import natural gas from Indonesia and Malaysia could potentially be repurposed to pipe green hydrogen, a solution being studied extensively in Europe.
 

Singapore town gas supplier City Energy is conducting a feasibility study with Gentari, Petronas’ renewable unit, on a proposed pipeline for importing hydrogen from Malaysia that it hopes can be operational by 2027.

The Hydrogen and Fuel Cell Association (HFCAS) expects some countries to begin producing green hydrogen by 2035.

Sembcorp Utilities has signed a deal with Indonesia’s power supplier PLN to explore the feasibility of producing green hydrogen there for export to Singapore, via subsea pipeline.

Mr Chen noted that the slow pace of green hydrogen production is a reflection of the global industry currently, rather than any foot-dragging on Singapore’s part, which has seen some “meaningful progress” through partnerships.
 

Mr Chen said the use of ammonia in gas turbines is still being tested and Singapore is an early adopter both of testing new turbines and retrofitting existing ones to work with ammonia.

The downside of ammonia is that it is corrosive and exposure to high concentrations of it in the air can result in blindness, lung damage or death, said Dr Victor Nian, the chief executive and co-founder of the independent think-tank Centre for Strategic Energy and Resources.

The downside of ammonia is that it is corrosive and exposure to high concentrations of it in the air can result in blindness, lung damage or death, said Dr Victor Nian, the chief executive and co-founder of the independent think-tank Centre for Strategic Energy and Resources.

“Singapore should consider a deeper dive into ammonia safety from the perspective of bunkering and large-scale storage, distribution and refuelling before its roll-out,” he added.
 

“Our ongoing estimates suggest that utilising geothermal heat for cooling purposes may prove to be quite cost-effective than for power generation,” he added. Other potential uses include desalination and hydrogen production.

Key changes needed from 2035 to 2050

Mr Chen noted that power sector emissions should peak in the late 2020s as the first wave of renewable power imports arrive. For instance, renewable electricity imports from Indonesia are expected to begin within the next five years.

After peaking, power sector emissions will begin to dip from about 22.6 million tonnes of carbon dioxide equivalent as at 2021 to net zero by 2050, in line with the national target.

“Singapore unfortunately has limited levers to decarbonise the power sector and will largely be dependent on the pace of power imports, faster roll-out of solar panels, and accelerating the development of green hydrogen through partnerships,” said Mr Chen.

While huge investments are being made in the technology to boost supply and cut the cost of renewable energy, energy demand must also change in the push for decarbonisation, he added.
 

Smart grids use digital technology, sensors and software to better match the supply and demand of electricity in real time, while minimising costs and maintaining the stability and reliability of the electricity grid.

By 2050, Singapore also hopes to have 50 per cent of its energy needs powered by “low-carbon” hydrogen.

But for that to happen, demand will have to grow to kick-start green hydrogen production at scale, the cost of hydrogen production must come down, and a greater international consensus must come about on the carrier for storing and transporting hydrogen, said HFCAS.

The organisation noted that some studies have estimated that the price of green hydrogen in Singapore could drop from US$12 (S$16.20) to $15 per kg today to US$3 to $5 per kg by 2050. This would likely make the price more competitive in comparison with the price of natural gas, which draws a tax on carbon.

By 2030, the carbon tax will be between US$50 and $80 per tonne. No plans have been made for the new tax rates from 2030.

Hopefully, by 2040 to 2050, most natural gas plants would be fully retrofitted to run fully on hydrogen, said the HFCAS spokesman.
 

Here are three scenarios outlining how Singapore could get to net zero by 2050

The most desired scenario would be where Singapore is able to rely on low-carbon hydrogen (40 per cent of electricity mix) and import electricity from multiple countries (another 40 per cent of electricity mix). Solar and geothermal energy would comprise about 20 per cent of the electricity mix.

In this scenario, countries rally together to tackle climate change, at the same time, technological advancements allow Singapore to decarbonise smoothly and achieve a diversified energy mix in 2050.

In a scenario where clean-tech energy developments stagnate, but countries still band together for climate action, a large portion of Singapore’s energy mix will still come from electricity imports (60 per cent).

These will likely be part of a regional grid, rather than bilateral energy trade, as this creates greater economic benefits and energy security for the region.

Hydrogen will form a smaller size of the pie (10 per cent of total electricity mix) and the Republic will still rely on some amount of natural gas, offset with carbon credits.

A third scenario is also possible, where the world is geopolitically fragmented, and development of technology accelerates closer to 2050.

Singapore makes proactive investments in new technologies to decarbonise, and low-carbon hydrogen becomes a key player, accounting for more than half of Singapore’s electricity mix.

Electricity imports are limited to only about 25 per cent due to slow development of regional partnerships. Building on earlier investments, Singapore deploys other low-carbon alternatives like nuclear.

Source: The Straits Times © SPH Media Limited. Permission required for reproduction.