The Environmental Protection Department has proposed new emission caps for power plants to improve air quality in Hong Kong and the Pearl River Delta region.

Under the Ninth Technical Memorandum for Allocation of Emission Allowances in Respect of Specified Licences gazetted today, annual emission caps of sulphur dioxide, nitrogen oxides and respirable suspended particulates will be capped at 2,852 tonnes, 11,144 tonnes and 367 tonnes respectively from 2026 onwards.

Compared with the emission allowances for 2024 set out in the previous technical memorandum, the newly proposed emission caps for sulphur dioxide, nitrogen oxides and respirable suspended particulates will each tighten by 9%, 10% and 6%.

The department said the tightened emission allowances for power plants will help improve the air quality in Hong Kong and the Pearl River Delta region, as emissions from the electricity sector accounted for 47% of sulphur dioxide, 28% of nitrogen oxides and 16% of respirable suspended particulates emissions in Hong Kong in 2018.

In setting the new emission caps, the department took into account the construction progress of new gas-fired units by the two power companies for replacement of coal-fired units scheduled to retire in the coming years. Other factors like the emission performance of existing generating units, the estimated import of electricity from Daya Bay Nuclear Power Station, the projected local electricity consumption and the projected electricity intake from renewable energy sources were also considered.

Hongkong Electric forecasts a drop of about 1.4% in electricity demand in 2026-27 compared to 2024-25, taking into account the energy efficiency and conservation measures in the Energy Saving Plan for Hong Kong’s Built Environment 2015~2025+ and the Scheme of Control Agreements. The decrease in electricity generation will reduce air pollutant emissions, allowing room for further emission allowance reduction.

CLP Power forecasts a slight increase of about 0.5% in electricity demand in 2026-27 compared to 2024-25. However, as Daya Bay Nuclear Power Station’s projected electricity import is expected to gradually resume after the completion of the periodic safety review in 2024, CLP Power anticipates a reduction of about 6% in local electricity generation, resulting in reduced air pollutant emissions.

The department noted that for new electricity works, it will allocate emission allowances based on the emission performance of a new gas-fired generating unit adopting the latest technology for emission reduction.

It will also review the ninth technical memorandum no later than 2023 to enable timely revision of the emission allowances.

The ninth technical memorandum will be tabled at the Legislative Council on May 12 for commencement by the end of this year, while the new set of emission allowances will take effect on January 1, 2026.