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

Under the eighth technical memorandum gazetted today, the annual emissions of sulphur dioxide (SO2), nitrogen oxides (NOx) and respirable suspended particulates (RSPs) from the power generation sector from 2024 will be capped at 3,150 tonnes, 12,430 tonnes and 391 tonnes.

Comparing to the emission allowances for 2022 set under the seventh technical memorandum, the proposed new caps will help tighten SO2, NOx and RSPs emissions by 40%, 29% and 20%. 

The department said the new caps have factored in the progress of the two power companies in raising local gas generation to around 57% of the total fuel mix for electricity generation by 2024, the progress in upgrading existing gas-fired units for improving their NOx emission performance and thermal efficiency, and the projected electricity intake from renewable energy sources and the projected electricity consumption.

The eighth technical memorandum will be tabled at the Legislative Council on October 30 for commencement by the end of this year, while the new set of emission allowances will take effect on January 1, 2024.

The department will review the technical memorandum again by 2021 to enable a timely revision of the emission allowances.