This update of David MacKay’s numbers suggests that it may be possible to eliminate CO2 emissions (at least in the UK) without relying on an extended period of nuclear power use.
But on the other side of the coin we have a more pessimistic view of wind power prospects.
Sources:
Can solar and wind power Britain? An update of David MacKay’s numbers
BP’s renewables boss calls U.S. offshore wind industry ‘fundamentally broken’