Though the design of Hong Kong Technical College is orientated towards an energy efficient architecture, recent recognition of the project demonstrates that this has not been at the expense of aesthetics. The three architects responsible for the design of the College share a Chinese background. They were inspired by the vernacular of Chinese architecture and sought to bring its essence to Hong Kong. Specifically, traditional Chinese courtyard houses and traditional Hakka houses inspired them  with idea of introducing a micro-climate within the college where the natural elements of light and air could be enjoyed.

Joel Chan makes the observation that "the new Governement restrictions on building design to promote energy efficient may well lead to more interesting architecture in Hong Kong". he said: "Aesthetic quality need not be sacrificed to make improvements in the energy efficiency. but the Governement could assist designers and developers alike by loosening some of the existing plot ratio guidelines. For instance, architectural features projecting out around the building perimeter which are placed there to improve energy efficiency, such as shading devices, could be left out of the GFA when calculating the building's plot ratio"
 

Elevation showing naturally ventilated courtyard

 

P&T were responsible for the design of Hong Kong Polytechnic, and on the basis of this experience and anecdotal evidence from the College's building effcicient than other similar buildings. Normally an energy comsumption rate over 20W per sq m would be expected, whereareas the College has achieved a consumption rate of 18W per sq m.

Hong Kong Technical College has been designed within the following energy efficient design parameters:

• The disposition and circulation design of the building minimize solar heat gain and maximize the possibilities for using natural cross ventilation.
• The design of the building envelope and the use of building materials minimize solar heat gain.
• The design optimizes the use of energy consumed in the air-conditioning system. the flexibility of using natural ventilation in lieu of air-conditioning is also explored.
• The design maximizes the possibilities of using indirect diffused natural lighting to assist artifical lighting and reduces the extent of energy consumption in lighting design.

For the elongated site, overall master plan focuses on a main academic plaza in the centre of the site which is flanked by two courtyards. Micro-climates have been created in these focal points and gathering places of the college by raising the buildings to the east to promote the sea breeze. No attempt has been made to shut out the environment. People inside the building facing on to the plaza and courtyards can enjoy the micro-climates through openable windows. Running from north to south on either side of the main plaza and set back from nosiy Tsing Yi Road is an ergonomic spine of teaching buildings and workshops. the basic 18m by 36m teaching wings are arranged with short sides facing east and west. These wings are connected by elevated connecting blocks which enhance the natural cross ventilation of the main concourse and the academic spine. the four main staircores and open lick bridge design also faciliate the natural flow of the southern breeze along the southern spine.

3.2 Building Envelope Design

A secondary landscaped concourse "Sky Deck" for student activities is formed on the roofs of the college with plenty of landscape planting, water features and covered walkways. In addition to the thermal insulation layer underneath the deck finishes, the Sky deck greenery and features provide extra protection to the building against solar heat gain through the roof. Non-habitat spaces, such as plant rooms and escape stairs, are located at the corners of the basic teaching wings and provide a heat buffer to solar heat gain through the external walls. the external walls are generally faced with a reflective metallic colour tile which further reduces the solar heat gain to the concrete structure. Grey tinted glass is used for all fenestration in order to reduce solar infiltration through the window areas.

3.3 Ventilation and Air-conditioning

	Working with the client to exactly locate the building's facilities, the architects were able to minimise circulation areas. With a very compact campus layout, a central chilled water system is an economical and efficient air-conditioning (A/C) system for the college. Air handling units are installed for large functional spaces such as installed for small laboritories and office areas which can reduce the amount of A/C wastage by having localized start-stop and temperature control devices. Primary air units are evenly spread around the building in eight locations. They are computer programmed to monitor the fresh air-temperature for better efficiency and make the necessary pre-treatment before supplying the air to the fan coil units. in order to reduce the wastage of energy due to inefficient operation of the normal chillers at night time, an additional smaller sized night-time chiller is installed for catering to the A/C demands of evening courses run by the College. To optimize the usage of cool air from the A/C system, the corridors and toilets are also designed to be cooled by spaces through transfer lourves in ceilings and doors.

3.4 Artificial and Natural Lighting

	Lighting levels have generally been designed in accordance with the recommendations of the CIBSE codes. recessed luminaries with transverse parabolic mirror reflectors which give good glare control and high light output are installed in office and lecture spaces. They provide the College with good working environments and a highly energy efficient lighting design. Due to the incorporation of deeply recessed facades, a narrow room depth design and the installation of shading devices; window sizes have been able to be significantly enlarged without increasing direct solar infiltration to the interior. Hence, indirect diffused natural lighting through the enlarged glazing can be utilized to assist the artificial lighting or even eliminate the need for artificial light during the day time. For some  functional areas with deeper building depths, such as the library, skylights with sufficient upstand and of appropiate size are incorporated to facilitate the use of diffused natural lighting to supplement the artificial lighting in the day time. These skylights further at to give the interior space the gentle, warm aesthetic effect that is only achievable with natural light.

Energy Efficient Building Award Scheme 1994 The Energy Efficient Building Award was presented to Hong Kong Technical College (Tsing Yi) by Mr AG Eason, the Secretary for planning, Environment and Lands at an award presentation ceremony held in the Landmark in Central.  The Energy Efficient Building Award was organised by the Energy Efficiency Advisory Committee and sponsored by the China Light & Power Co. Ltd and the Hong Kong Electric Co. Ltd. The aim of the scheme is to promote awareness of the importance of energy efficiency among both the genral public and professionals.

• Hong Kong Technical College (Tsing Yi) - Aesthetic energy, Building Journal Hongkong China, July 1994, pp. 85-89.