Wind turbine farm owned by PacifiCorp
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Green investment 'needs to treble'

Scientists are calling for a big shift to renewable energy as a solution to the problems caused by global warming.

Scientists from around the world are calling for a big shift to renewable energy as a solution to the problems caused by global warming.

The Intergovernmental Panel on Climate Change is expected to recommend at least a trebling in the use of wind and solar power.

Matt McGrath reports.