The government has given permission for a major new gas pipeline that will supply a £400m power station to be built on the edge of Plymouth.
The power station site has already been cleared for work to start
The pipeline will cross several local authority boundaries on its journey from Ottery St Mary in the east to Lyneham in the west.
Certain sections of the pipeline will use existing pipes that can be adapted to take higher pressure gas.
But much will be freshly dug, with most of the work happening in 2007.
Planning consent for the pipeline has been given by the Department for Trade and Industry.
BBC South West business correspondent Neil Gallacher said: "Preparatory works at the site of the gas station itself are already well under way at Langage.
"Now consent has formally been given for the other main aspect of the development: the high pressure gas pipeline that will feed the power station.
"This will be constructed by the National Grid, formerly Transco."
At least 300 jobs are expected to be created in the construction of the power station and a business park is planned on 80 acres around it.
The station, to be run by Centrica, could start commercial operations in the winter of 2008/09, providing electricity for one million homes and employing about 40 people long-term.
The plant got planning permission six years ago, but questions about its economic viability delayed the start.