Sun Powered

A Japanese near-disaster has many wondering if solar’s time has come

The escalating earthquake-related crisis at Fukushima’s nuclear power plants has beyond adoubt caused panic. Not only has it sparked a new wave of criticism of nuclear energy, it’s become a rallying cry to give solar energy a second thought. Freelance journalist Leila Chan Hiu-lui is one of the few in Hong Kong to experiment with solar energy in her new eco-village house in the New Territories. She’s getting ready to install the familiar large solar panels on her rooftop to generate electricity to light up her garden.

“I would love to play with all kinds of renewable energy. Solar energy is only one of them,” says Chan, who is moving into her new home this month. “Using solar heaters to boil water is what I would like to try in the future.”

While tourists love the sun-kissed beaches of the city, researches have long suggested the abundant and readily available sunshine in subtropical Hong Kong is an asset. Over the past 20 years, Hong Kong has received an average of about 13 MJ/ m2 of solar radiation every day according to the Hong Kong Observatory, compared to only 9 in London.

“Wind energy is less reliable in summer, even water flowing downhill from Victoria Peak is insufficient to generate electricity,” explains Wallace Chan Siu-wai, scientific officer of the HKO. “Relatively solar energy has greater potential. If 10 percent of Hong Kong’s total construction area is installed with solar panels, solar energy could account for about 4 to 5 percent of the city’s energy consumption.”

The most common ways in Hong Kong to exploit solar energy is either generating electricity from solar photovoltaic, or boiling hot water with a solar heater. It’s not hard to spot some of the photovoltaic installations around town, from the solar lamps in Hong Kong Park to the rooftops of public facilities like Science Park, Kowloon Hospital and the Museum of Art.

Last year, Hong Kong’s first standalone solar energy power system was built on Town Island in Sai Kung to tap this natural resource. CLP used more than 100 solar panels to replace three diesel electrical generators, supplying power to the chapel, kitchen and dormitory to a drug rehabilitation centre. However, the use of solar energy is still far from popular in households. A major challenge is the rigid architectural design of most existing residential blocks. “Even squeezing out space for the large panels can be difficult, not to mention whether ceilings can support those heavy panels,” points out the HKO’s Chan. Multiple ownership in residential buildings is another headache, as consensus is hard to reach, and living green does come with a cost. “The cost [of solar energy] is comparatively higher than traditional electricity generation, thus making the payback period longer,” CLP admitted. “Hong Kong’s solar energy market is still at its start-up stage.”A solar energy system worth $3 million was recently installed in a Lam Tin public housing estate. It’s expected to reduce annual electricity bills by $43,000 but will take the government a ridiculous 70 years to break even.

“Technological advancement is the key,” says Chan. “But it takes time, too,” he continues, listing research exploring various possibilities like energyabsorbing paints and a polymeric photovoltaic solar thin film, which could be stuck on walls and windows. “Perhaps one day a heavy solar panel will become as thin as the retina display on your iPhone. Who knows?” Don’t forget: electricity itself was once fantasy.