A FORMER Labour cabinet minister is set make a fortune when the country switches to using low-energy light bulbs.

Lord Barnett, who was Treasury chief secretary two prime ministers during the 1970s, is a shareholder in Mercury Recycling Group, which is expected to see its value soar during the switch over from conventional lighting.

The company specialises in the safe disposal of mercury found in the new “eco” bulbs and already has contracts with schools and local authorities.

By the end of 2011 traditional incandescent bulbs will be phased out for the new “green” alternative as Britain heads an EU-wide switch over. The government has also signed up to a Europe-led directive on the disposal of hazardous waste.

Joel Barnett, 85, has 2.4m shares in Mercury and is the company’s non-executive chairman. He was an original investor when the company was founded in 1995 and has a 7% stake. The group floated on the stock market in 2001.

Lord Barnett’s stake is currently worth £300,000 but could rise dramatically as more low-energy light bulbs are used.

The Environment Department advises the public to take the new bulbs to council recycling plants, to be picked up by contractors — such as Mercury Recycling Group — and sent to specialist plants for recycling.

Anticipating rapid growth the company has opened a new centre in Trafford Park, Manchester, where the toxic mercury will be removed. A company report said the strict recycling measures were “bringing increased sales every month”.

Mercury have already seen sales rise by 10% in the 2007 calendar year to 2.7m and the company registered pre-tax profits of £445,000.

In the first six months of last year, sales rose from 1.3m to 1.5m and operating profit increased by 34% to £312,000.

Lord Barnett, denied that he had used knowledge of government plans to influence his investing. “I have never spoken in the House of Lords on an issue in which I have got an interest,” he told the Mail on Sunday.

“I have not the faintest bit of parliamentary or ex-ministerial knowledge of anything except that I could see it was an industry that had a great potential.”

Lord Barnett served under James Callaghan and Harold Wilson and was made a life peer in 1983.

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