Energy-saving light bulbs not so efficient

PUBLISHED : Saturday, 16 May, 2009, 12:00am
UPDATED : Saturday, 16 May, 2009, 12:00am

Most energy-saving light bulbs sold in the city are of a lower wattage than claimed and some are not as energy efficient as they should be, a Consumer Council study has found.

The consumer watchdog conducted tests on 20 models of compact fluorescent lamps, also known as energy-saving bulbs, to examine performance and safety.

All but three samples were found to have a lower wattage than indicated on their packaging, which meant they were not as bright as they should be. In five samples, the difference between the actual and claimed wattage was 15 per cent or more.

The biggest discrepancy was seen in a Starwise Industrial light bulb, which claimed 11 watts but was measured as only 4.4 watts, a shortfall of 60 per cent.

Ron Hui Shu-yuen, vice-chairman of the council's publicity and community relations committee, said consumers were being misled if the actual wattage was lower than indicated on the packaging of the bulb.

'Lamps with higher wattage are usually priced higher in the market. It's actually a kind of cheating if these lamps fail to live up to what they have claimed,' he said.

Meanwhile, tests showed that the lumen output - an indicator of the level of illumination - in half of the bulb samples fell significantly after being used for 2,000 hours.

'It's normal to see a certain degree of reduction in lumen output after a period of usage,' Professor Hui said, adding that a dramatic drop after a short period of use would force consumers to replace the bulbs. 'It's an extra cost for consumers.'

To evaluate a bulb's energy saving features, the council measured the amount of light produced for every watt. Nine of the 20 samples were 'excellent' or 'good'. Three - Ikea, Sunshine and B&Q - fared poorly. In separate safety tests, four samples failed international standards.

The council has passed the test results to the Customs and Excise Department, where a spokeswoman said follow-up action would be taken.

'Customs will take legal action if there is evidence of a breach of the Trade Descriptions Ordinance ... by applying fake descriptions on products,' she said. The penalty is a maximum of five years' jail and a fine of HK$500,000, she added.

Several compact fluorescent lamp producers responded to the council's survey yesterday, vowing to improve product quality.

A spokesman for Starwise said the bulbs tested had been made by a mainland factory and the company would stop using the manufacturer. Sunshine said it had stopped making the type of bulb tested before the survey was released.

However, a B&Q spokesman said the voltage used to test bulbs differed from that used by the council, and had revealed no problems.