Singapore is a step closer to importing solar energy from Australia via a huge undersea cable, after giving the green light to an ambitious project that could provide a solution to other countries that are trying to make the shift to renewables.
Australian company Sun Cable plans to build a 4,300-kilometer subsea cable which will supply the Southeast Asian city-state with just under 10 percent of its energy needs.
Solar energy will be sourced from a 12,400-hectare solar farm in Australia’s Northern Territory, with some of the electricity generated also supplying the state’s capital, Darwin.
Singapore’s Energy Market Authority has granted conditional approval to Sun Cable, stating that the project is “technically and commercially viable.” The current timeline for the Australia-Asia PowerLink sees the cable being fully operational by 2035.
Singapore has been forced to look further afield for more environmentally friendly ways to meet its energy needs, largely due to a scarcity of available land.
Philip Andrews-Speed, senior research fellow at the Oxford Institute for Energy Studies, said researchers in Singapore had investigated how much energy could be produced from solar panels in the country.
“It was building on reservoirs, it was building over car parks and building over motorways. They came up with a number, but it was nowhere near what is needed.
“It’s also difficult to do much with marine energy because the seas are so busy,” Andrews-Speed told VOA.
The Southeast Asian financial hub plans to import around 6 gigawatts of low-carbon electricity by 2035 and has conditional approvals in place with projects in Indonesia, Cambodia and Vietnam.
It currently imports 100 megawatts of hydropower from Laos through a cross-border project that includes Malaysia and Thailand.
Whilst Singapore has looked to its neighbors to import renewable energy, the Sun Cable project would be a significant step up in terms of scale and logistics.
“A grid connection for 4,200-kilometers subsea has never been done before and has never been remotely delivered on. It is a very aspirational, game-changing proposal,” said Tim Buckley, founder of the independent research group Climate Energy Finance.
“There are significant geopolitical, financial and technical obstacles to this project and any project that goes subsea,” Buckley told VOA.
One of the major challenges facing Sun Cable is the depth and diversity of the waters that the cable will be running through.
“They need to figure out whether they will be passing through tectonically unstable undersea terrain,” said Victor Nian, co-founder and chief executive officer at the Centre for Strategic Energy and Resources.
“We know that Indonesia is sitting across the Pacific ring of fire, so if there are earthquakes or volcanic activity undersea, how would that impact the cable?” Nian told VOA.
The sheer cost of the project has also proven problematic, with estimates coming in at $13.5 billion. Sun Cable ran into financial difficulties in January 2023, but was rescued by Australian tech billionaire Mike Cannon-Brookes.
Even if the project does get off the ground, Singapore may be forced to pay a premium for the delivery of green energy, warns Buckley.
“Solar from the Northern Territory is very, very cheap, but by the time you deliver that to Singapore, it's exceptionally expensive because of the transmission costs.”
Whilst there is still plenty of work to be done to make the Sun Cable vision a reality, similar projects have been completed elsewhere, although on a significantly smaller scale.
The current largest subsea power cable runs 760 kilometers below the North Sea, servicing the United Kingdom with clean energy from wind turbines and solar panels in Denmark. It’s one of a number of cables linking the UK with Europe.
“They play a huge role in underpinning grid reliability and diversity and security of supply, and have played an absolutely central role in the UK shutting its last coal fired power plant,” said Buckley.
Britain’s shift to renewables could further benefit from another ambitious subsea cable plan, with green energy sourced from a North African desert.
“The Xlinks project seeks to link renewable energy produced in Morocco with the United Kingdom via a 4000km subsea HVDC cable,” said Mutya Yustika, an energy finance specialist at the Institute for Energy Economics and Financial Analysis, via email.
The project is “similar in scope and nature to Sun Cable” and would allow the UK to tap into “abundant natural resources,” Yustika told VOA.
Like Sun Cable, the Xlinks project faces numerous regulatory hurdles before work can begin, with a final decision to be made by the British government.
Whilst these projects require cooperation among a small handful of countries, Buckley has voiced confidence that a global green energy power grid will one day be in operation.
“International grid connectivity will play a major role in helping to drive grid reliability, decarbonization and the optimization of matching energy generation to energy use."
Buckley sees Southeast Asia as one of the key starting points for a global grid, pointing to China’s involvement in the region.
“China Southern State Grid operates the Laos grid and they're underwriting the development of low-cost renewable energy."
This green energy can then be exported across the region, generating revenue for Laos where there is minimal domestic energy demand, says Buckley.
