The governors of western states including California, Nevada, Utah and Wyoming have reportedly agreed to build an estimated $20 billion electricity transmission system.

The so-called Frontier Line system would supply areas such as California, Las Vegas, and Salt Lake City from nearby energy producing states. Montana may also join the effort, which would see infrastructure built across the western US.

The project is expected to need as much as $5 billion in investment on transmission lines and associated equipment and a further $15 billion in generation for as much as 12 GW. Up to 6 GW of this would be sourced from coal-fired capacity and the remainder from wind.

A committee is being formed to develop feasibility and financing plans for the project, which may be operational by 2011.