Energy Use

Energy use is a main environmental aspect in the performance of buildings. At the Architectural Services Department, we set an exemplary example for the construction industry in minimising energy use in the buildings that we build.

Lighting and air-conditioning, which account for approximately 70% of total energy usage in commercial buildings, provide the most obvious area for savings. In our design, we continue to adopt the use of energy-efficient devices such as variable speed drive for motor equipment, high-efficiency chillers, heat recovery chillers, thermal wheel, cooling towers, energy-saving T5 flourescent tubes and electronic ballast, motion sensors and photo cells to achieve our goal of energy conservation and efficiency. Altogether our investment in this regard amounted to $119 million last year, against a total project sum in of $8.2 billion.

Energy Conservation in Daily Operations

We actively seek opportunities to enhance energy saving and conservation in our office areas, which consist of 10 storeys of the Queensway Government Offices, the APB Centre in Tokwawan and two leased commercial buildings in Wanchai and Kwun Tong. We have set up an energy audit team to assess the effectiveness of the green measures implemented, and identify more appropriate initiatives to save energy. Some of the progress we made in 2004 is listed below.

Energy Conservation in Daily Operations

Objectives	Targets	Measurement	Achievement in 2004
Save energy for operation of lighting, office equipment & fan coil units in meeting rooms and office areas	Reduce electricity consumption by 20% after lighting retrofitting	Measured in terms of kWh and percentage reduction	Achieved
	Reduce electricity consumption (kWh/ m2) by 3% at APB Centre compared to base year 2002	Measured in terms of kWh/m2and percentage reduction	Achieved. Consumption for 2004 was 241kW/m2, a 8% reduction from base year

Design and Construct Energy Efficient Government Facilities

Raising the bar of building energy efficient buildings, we have established a stringent overall thermal transfer value (OTTV) of not more than 23W/m², compared to 30W/m² of the statutory requirement. OTTV is a yardstick used to measure how well a building is in terms of solar heat gain and thermal conductance. We also recommended a target of 18W/m² OTTV for building design in order to reduce the overall heat gain or loss from the building structure to the environment. Our long-term targets achievement in energy is listed below.

Design Energy Efficient Government Facilities

Objectives	Targets	Measurement	Achievement in 2004
Energy conservation	Achieve OTTV of not more than 23W/ m2 for 92% of all new projects with air-conditioning, and not more than 18W/ m2 OTTV for 30% of projects	Measured in terms of number and percentage of projects.	100% of projects achieved OTTV less than 23W/ m2, 70% of projects with less than 18W/ m2
Improve energy efficiency of new installations	Use water-cooled heat rejection system for central air-conditioning in not less than 70% of new projects	Measured in terms of number of projects	77.8% (7 out of 9 projects) used the system
	Use occupancy sensor for air-conditioning and lighting in not less than 80% of new projects	Measured in terms of number of projects	93.8% (15 out of 16 projects) used occupancy sensors
	In not less than 70% of new projects, the efficiency of driving motors for lift and escalator should not be less than the benchmark 85%	Measured in terms of number of projects	93.3% (14 out of 15 projects) met the benchmark
Use energy saving lighting fittings in maintenance and refurbishment projects	Achieve at least 20% energy efficiency	Measured in terms of kWh and percentage reduction	Improvement in energy efficiency is 23.14%

According to our estimation, the annual savings in electricity cost and CO₂ emissions avoided in completed projects due to the application of energy saving initiatives are shown below. The normalised ratio (showing CO₂ avoided per unit of contract value) demonstrates that our emission has been largely constant since 2002.

Savings due to Energy Efficient Initiatives

Year	Avoided CO2 Emissions in ,000 Tonnes	Saving in HK$ in million	Contract Value ($ billion)	CO2 Normalised Ratio (by Contract Value) [1]
2002	48	85	5.40	8.89
2003	62	108	7.00	8.86
2004	68	119	8.20	8.29

Note: The CO₂ conversion used is 1MWh = 0.57297 tonne (from China Light & Power)

Note: The CO₂ figures for year 2000 - 2003 are restated to conform to the recently-available CLP factor used for 2004.

¹The normalised ratio is calculated by this formulae: Avoided carbon emissions/Contract Value x 10⁶

Renewable Energy

The use of renewable energy, particularly solar panels, is becoming a feature of many of our buildings. As the normalised ratio in the table below testifies (which shows changes in PV use per unit of contract value), we have completed considerably more PV panels over the years. This is consistent with the Government’s first sustainable development strategy, which aims to generate one to two percent of Hong Kong’s electricity supply by renewable energy by 2012.

Building-integrated PV & PV Panels at EMSD Headquarter

PV panels at EMSD Headquarter roof top

Note: Since 2002, the method of compiling PV figure has been revised to reporting PV panels completed, as opposed to reporting PV panels under design or construction in previous reports.