The Senoko Power plant in Woodlands uses natural gas instead of oil to produce electricty, a switch that has saved 2.5 million tonnes of carbon annually since 2004 - equal to taking all the cars off the road for a year.

For achieving that mean feat, the firm will be awarded the President's Award for the Environment - the country's highest environmental accolade.

'This is the blue ribbon of environmental awards,' said Senoko president and chief executive officer Roy Adair. 'Needless to say, we're very honoured.'

He will be joined by representatives from fellow winners Alexandra Hospital and Southwest Community Development Council at the award ceremony at the Istana on Tuesday evening.

Launched in 2006, the award recognises individuals, organisations and companies for their green contributions and excellent environmental track record. Three winners are selected every year.

The winners' 'committment to the environment' made them stand out from 25 other nominations, said award selection committee chairman Tan Gee Paw.

Senoko spent $650 million in 2000 to upgrade three of its oil-fire power stations to run on natural gas. Another $750 million will be spent to convert three more plants by 2011.

The company produces about a third, or 3,300MW, of the country's total annual electricity consumption.

The power company has also pumped $7 million into building its own desalination plant in 2004, which provides up to 80 per cent of the power plant's water needs, said Mr Adair.