If the project succeeds, it would give Montana's burgeoning wind energy industry room to grow _ an expansion that to date has been limited by a lack of lines to move power out of the state.

Toronto-based Tonbridge Power Inc. already is building a $215 million transmission line that will carry wind power along a 200-mile (322-kilometer) route between Lethbridge, Alberta and Great Falls. The company now is considering a 100-mile (160-kilometer) link between that line and another in southern Montana that connects to electricity markets in the Pacific Northwest.

The new project would be known as the Green Line. Tonbridge CEO Johan van't Hof said Friday it would likely carry only wind power.

Tonbridge would allocate at least 500 megawatts of capacity to the North American subsidiary of Dublin wind developer Gaelectric.

Gaelectric vice president Van Jamison said that equates to about $1 billion worth of wind energy projects. The company has about 100,000 to 150,000 acres under long term lease in the Great Falls area for future wind farms, he said.

"This is hand-in-glove," he said of the plans for the Green Line. "Both pieces have to come together. Otherwise, you end up with a transmission line with no one to use it, or a wind farm with nowhere to send the power."

Gaelectric also has been negotiating a potential deal with another Canadian company, TransCanada, that has proposed a $3 billion transmission line from central Montana to Southwest markets.

Jamison said those negotiations were continuing and that his company could eventually develop enough wind power generation that it would need both lines. He said the company has leases on land across the state, but declined to give an overall figure.

Gaelectric and Tonbridge have committed to spending a combined $500,000 on a yearlong feasibility study for the Green Line. If the project moves ahead, completion is forecast for 2013.

Van't Hof said it was too soon to predict how much the Green Line would cost or whether it would qualify for stimulus money.

Tonbridge started construction this week on its other transmission project, known as the Montana Alberta Tie Line, or MATL. The line got a major boost from the Obama administration in September when the U.S. Department of Energy announced it would provide up to $161 million in loans using federal economic stimulus money.

Contracts are in place with three companies _ Wind Hunter, NaturEner and Invenergy _ that want to use the line's 600 megawatts of capacity for several planned wind farms.

NaturEner, which owns the 210-megawatt Glacier Wind Farm in Glacier and Toole counties, announced plans in September for an $800 million, 309-megawatt wind farm north of that project.