A $370 million plan to feed Victoria's booming renewable sector into the national energy grid would deliver almost double the benefit by driving down electricity bills and stabilising the network.

The Australian Energy Market Operator's recommendation of a planned upgrade to transmission networks in the state's west, to be released on Friday, has found major works to capture about 6000 megawatts of wind and solar power would be critical to driving down energy costs.

The mass connections, through upgrades to transmission lines and new sub-stations across the region, would extend out to 2025 by linking the network from the south coast near Terang to solar farms on the Victorian-NSW border.

The project would also ease the strain on the nation's ageing coal-fired fleet, as well as improving export capacity through the Victoria-NSW interconnector, resulting in major savings in NSW and Queensland.