IOI and TNB plan 500 MW of solar with a 1,000 MWh battery for DayOne data centres
Victoria Shinder1 min readA 500 MWac solar project paired with a 250 MW / 1,000 MWh battery energy storage system is planned on about 1,300 acres in Bahau, Negeri Sembilan, Malaysia, pv magazine reported on 4 November.
The developer is IOI Corporation, one of Malaysia's largest integrated palm oil producers, in partnership with Tenaga Nasional Berhad, the country's largest utility, and a consortium of small and medium-sized companies that was not named. According to IOI, the project is backed by TNB's long-term renewable offtake agreement with DayOne Data Centres, a Singapore-headquartered digital infrastructure company, under which DayOne is expected to buy up to 500 MWac of renewable energy over 21 years for its Malaysian data centres, as announced in June 2025.
It is IOI's first large-scale renewable investment under the Corporate Renewable Energy Supply Scheme, CRESS, which lets corporate buyers procure renewable power directly from independent developers through the national grid. In September 2026 Malaysia revised the scheme to improve bankability, introducing a fixed system access charge of MYR 0.14 per kWh for qualifying firm renewable supply projects and a minimum ten-year contract term; projects must start commercial operation by the end of 2028 to get the reduced charge. At that point 11 developers and eight corporate buyers had registered projects totalling about 3.15 GW.
The article notes that data centre growth has raised concerns in Malaysia about supply, grid capacity and water, and that uncertainty over grid access charges had weighed on corporate renewable projects.
What it means
Four hours of storage behind a 500 MW plant is what turns solar into the firm supply a data centre contract needs, and the revised CRESS charge rewards exactly that.