SaskPower says it's working with two private companies on "clean coal" technology that could allow it to pump a proposed power plant's greenhouse gases underground.

The Crown-owned company hopes to build a 300 megawatt, $1.5 billion power plant somewhere in Saskatchewan by 2011.

On Monday, it said it's teaming up with some international power and gas firms, Babcock & Wilcox Canada and Air Liquide, to develop the technology that could allow it to sequester 90 per cent of the plant's carbon dioxide (CO2) — 8,000 tonnes a day.

The gas, which scientists believe is the main contributor to the "greenhouse effect" that's warming up the planet, would either be stored in underground caverns or used by oil companies to help extract oil from nearly-depleted reservoirs. Part of the technology will involve removing nitrogen from the combustion air in the boilers.

Although there are many CO2 sequestration projects at various stages of development around the globe, SaskPower says this would be the first "near-zero emissions" plant of its kind to be built on a commercial scale.

SaskPower uses coal to generate more than half of its electricity, a practice environmental activists have criticized.

The company says over the next two to three decades, it will be making major decisions about refurbishing or replacing virtually its entire generating fleet.

The proposed "clean-coal" plant is still at the feasibility stage, however.  SaskPower says it will make a decision on whether or not to proceed by mid-2007.