This year, the Tsim Sha Tsui East Property Developers Association - a consortium led by the Sino and Kerry groups - hired Lo's company, LED Artist, to design a Christmas lighting scheme for nine of its buildings. Mainly located along Salisbury Road, they include the Tsim Sha Tsui Centre, Wing On Plaza and hotels such as the Nikko and the Kowloon Shangri-La.

Hongkong Land has also tapped the LED-only lighting firm to decorate five pedestrian bridges connecting its buildings in Central.

This is the first time the developers are using all LED lights for their Christmas facades, says Lo.

Although LED (light-emitting diode) lights cost about 10 times more than incandescent ones, they are gaining popularity for their eco-credentials. One LED bulb uses 2.5 volts compared to 15 to 25 volts for incandescent, representing energy savings of up to 90 per cent.

Casinos in Macau have long used them because they emit brighter light and last up to 50 times longer than incandescent lights.

But Lo says landing a landmark facade such as the Tsim Sha Tsui Centre wasn't easy. 'Property developers are very practical. They still pick the cheapest, fastest solution, even if they see better execution elsewhere.'

LED light displays also take almost twice as long to set up. 'It took us 35 days to install everything. It would have taken longer if all of us weren't working round the clock,' Lo says. By comparison, the incandescent display on The Peninsula hotel will take only two weeks to install.

An LED Artist engineer says they first bend stiff wires into the shape of the design, then secure each bulb with a tie before attaching the frames to the outside of the building. The same method is used for incandescent lights.

But while the latter can be plugged into one power line, each LED light needs its own electrical supply and wire, and must be individually programmed.

However, Sino accepted LED Artist's proposal this year because, besides putting on a beautiful festive display, they also want to help protect the environment, a company spokesman says.

Design work for the Tsim Sha Tsui buildings began during the summer. After receiving his brief, Lo and his team of designers pored over old photos of Christmas lighting.

'In the past, you'd see very simple graphics that looked more like primary school illustrations,' he says. 'We wanted something more modern, more abstract than the usual cutesy Christmas images.

'But I guess since we're a design company, sometimes we go overboard. We had to remember that the target market was still mostly kids and parents. So what you see now is the result of a few months of going back and forth with the client.'

This year, the Sino group moved away from using static cartoons for the Tsim Sha Tsui Centre. The graphics are still simple - Christmas trees, Santa Claus hats, presents and snowmen - but the colours change constantly on a three-minute loop.

'We can make the loops longer as we go,' says Gary Crestejo, business director at LED Artist. 'It depends if the client is willing to pay for it.'

Although LED lights have become trendy, Crestejo says the problem is some lighting companies use them only as an afterthought or because clients ask them to.

Each bulb can be manipulated to give 16.7 million different colours. Incandescent bulbs only emit white light and any colour typically comes from a gel coating.

Lo says the most labour-intensive parts of the project were dealing with the circuitry - hiding the wires and programming the lighting sequence. The light fixtures are controlled by a computer program that dictates the timing and colours of each bulb.

'Programming is quite a long process actually, because we're controlling more than 20,000 pixels on the facade,' Lo says.

At the Tsim Sha Tsui Centre, the program is run by a computer placed behind the facade. But Lo hopes that by next year he will be able to control the lights from a remote location.

Settings for incandescent lights, however, are limited to turning the power on or off.

Later this month, Lo will plug in the LED mesh, which is being draped over Hongkong Land's five pedestrian bridges in Central.

'This is a new product which creates a see-through screen which you won't notice during the day,' he says. 'But at night when it is turned on, you can see a graphic design.'

A board member of the Microwave Media Art Group, Lo is better known for his multimedia installations and artistic displays for concert halls than decorating facades of commercial buildings.

So the Christmas lights project was a new challenge for his firm, Lo says. 'It was time-consuming and commercial, but the way we've designed and executed it is quite artistic, I think. Best of all, it is much better for the environment.'

The festive lights at Sun Hung Kei Centre will be switched on in early December, just ahead of the fifth East Asian Games. You can get an early peek when it begins testing the lights next week, if the weather clears, a spokeswoman says.

Some shopping complexes have already switched on their seasonal displays, with Harbour City and Times Square the first to do so. This year, Harbour City only strung lights along the boulevard leading to the mall entrance and around the door.

Andy Tong Siu-wing, the designer behind the display, says the Harbour City entrance features 200,000 LED bulbs mixed with other types of lights and mechanical features, such as figures of fairies and balloons.

'This year the atmosphere was gloomier because of the economy, so we made the decorations brighter and more spectacular,' says Tong. 'Lighting up the buildings is a tradition. It's done every year to create more photo opportunities, which in turn brings more customers to the malls.'