Energy-hungry office buildings could slash power use by 30 per cent by tweaking lighting and air-conditioning systems, a green group says.
Buildings account for 90 per cent of the city's electricity use and two-thirds of greenhouse gas emissions, but most owners and tenants do not have the incentive to go green, the Hong Kong Green Building Council says.
In November, it launched its Building Energy Performance Recognition Scheme to cut office energy use via a benchmark and labelling scheme.
It helps offices analyse energy consumption and assess savings.
Participating companies are then ranked on a performance scale - green, bronze, silver, gold and platinum - and awarded corresponding labels. Assessors then recommend ways they can cut use further.
"This is a powerful scheme because it allows companies to be compared with others," council director Cary Chan Wing-hong said.
"Nobody will want to fall in the lower percentile and this will eventually drive improvement."
Through small adjustments, Swire-managed One Island East in Taikoo Place has become the first building to receive the top platinum award.
The installation of T5 fluorescent tubes has helped all four levels of Swire's offices reduce energy consumption by 13 per cent, according to the company.
Photocell sensors installed near windows that detect daylight and dim lighting automatically, as well as occupancy sensors, have helped cut energy use by about 4 per cent.
Tweaks to temperature and humidity in the energy-intensive computer-server room have also helped the company cut energy use by 10 per cent.
"It proves that a company does not have to change or make huge investments to see results," said Chan, who is also head of technical services and sustainability at Swire Properties.
The scheme is part of the council's pledge to see buildings cut energy use by 30 per cent of 2005 levels by 2030.
Greenpeace campaigner Yeung Man-yau welcomed the move, saying it was a good first step, but urged the council to do more to promote the scheme to smaller businesses.
The green group last year studied energy-efficiency audit results and found that electricity use by the most and least energy-hungry buildings could vary as much as 17-fold.