The Energy Market Authority (EMA) and SP Group (SP) will pilot an ice thermal Energy Storage System (ESS) at the George Street Substation. This will be the first time that EMA and SP are installing an ice thermal storage facility located on its own, outside a district cooling plant. Such ice thermal storage facilities are traditionally located within a district cooling plant.
The pilot will optimise space usage within the substation and be completed in the third quarter of 2026 as part of the substation’s renewal works. This ESS will add up to 1,500 Refrigeration ton-hour (RTH) of ice thermal energy to the Marina Bay district cooling
network operated by SP. This will enable the curtailment of up to 2 megawatts (MW) of electrical load – the equivalent of 170 4-room HDB flats for a day. This will also contribute towards EMA’s target to deploy at least 200 MW of ESS beyond 2025.
ESS can help to address the issue of supply intermittency, as renewable energy such as solar power fluctuates due to weather conditions. The stored thermal energy can also be discharged to power the district cooling plant and shave peak load demand. This will help to balance the electricity load, thereby reducing intermittency and enabling the grid to be more resilient.
On this pilot’s importance, Mr Ngiam Shih Chun, Chief Executive of EMA, said, “Energy storage systems (ESS) help to address solar intermittency and can enhance the resilience of our power grid. EMA is pleased to partner SP Group on a thermal ESS at the George Street power substation. If successful, more thermal ESS can be installed islandwide, which will support Singapore’s target of having at least 200 MW of ESS beyond
As part of the pilot, SP will install 3,000 refrigeration tons (RT) of chiller capacity at the substation to support the future expansion of the Marina Bay district cooling network, bringing the total installed capacity of the network to 73,000 RT. This will allow SP to provide sustainable cooling to more buildings in the Marina Bay vicinity and surrounding areas such as Boat Quay.
Mr Stanley Huang, Group CEO, SP Group, said, “SP Group has built deep capabilities in operating Singapore’s national grid and upholding its world-class electricity network reliability. This pilot will provide valuable insights on leveraging existing electricity infrastructure to support sustainable energy developments. In exploring the operation of thermal energy storage in more locations, we aim to strengthen the resilience, reliability and sustainability of both our electricity and district cooling networks. This will also enable us to incorporate more renewable energy sources to empower a low-carbon, smart energy future for Singapore.”
The thermal ESS will also enhance SP’s participation in demand response, mitigating high prices during times of tight electricity supply. SP’s district cooling operations at Marina Bay are currently a key demand response provider in Singapore, with five thermal storage tanks contributing up to 11 MW of electricity load curtailment capacity. With the additional thermal energy storage from the George Street Substation, SP can increase its electricity load curtailment capacity for demand response during peak periods which will result in overall system savings.