Hong Kong power imports test grid and tariff stability

Long construction timelines and rising data-centre demand could complicate plans to raise zero-carbon electricity to 70% by 2035.

Hong Kong’s rising reliance on imported zero-carbon electricity will test whether grid planning and long-term contracts can keep pace with higher demand without weakening supply reliability or tariff stability.

An upgraded transmission system completed by CLP in March 2026 is expected to lift imported zero-carbon electricity from about 25% to 35% of the city’s power mix. Wing Tsang, Assistant Manager at Civic Exchange, said the increase supports Hong Kong’s goal of sourcing 60% to 70% of electricity from zero-carbon energy by 2035.

“After the project is completed, it will increase the share of imported zero-carbon electricity to 35%,” Tsang said.

A planned electricity facility at Tseung Kwan O Area 132 could add another 30 percentage points once completed, but the project will require high-voltage direct-current submarine cables, environmental assessments and early system design.

Tsang said major energy infrastructure typically takes 10 to 15 years to plan, build and commission. The government has already extended an imported electricity contract until 2034 and is applying a similar long-term approach to the Tseung Kwan O project.

The Northern Metropolis will add another constraint. The district is expected to host data centres and support cross-boundary data flows, lifting electricity demand by 9%. Tsang said planners must coordinate new import capacity with local grid expansion to preserve stability.

Greater dependence on cross-border electricity also raises supply and pricing questions. Under Hong Kong’s Scheme of Control Agreement, local power companies must maintain standby generation for emergencies.

Tsang said the agreement also supports investment by allowing an 8% return on average net fixed assets. Tariffs are divided between a basic charge and fuel-cost adjustments.

She added that a larger zero-carbon share should make fuel-cost adjustments more predictable and reduce exposure to volatile fuel markets, provided imported supply and domestic backup capacity remain properly coordinated through the next planning cycle.