Wind is not a long term solution, and will never generate 15% of our needs and is very inefficient as far as land use goes.
Within a decade we will be able to shift the majority of oil based energy consumption (ie cars) onto things that depend on electricity. This means that we will need far more capacity, that only nuclear or coal can provide.
Wind is only a stop gap measure due to the (relatively) fast building speeds of the turbines - it will help avoid the blackouts that are forecast until we have nuclear online (the forecast was for 2012, but the recession has probably pushed that back to 2015-18 at least).
If we were to build nuclear NOW, we would have them online by 2015/18 - but we aren't (see reply below).
All I have heard from this government about nuclear is that "we will built it ... at some point", there have been no contracts negotiated or given out, no sites confirmed and no expected completion dates.
Hell, we haven't even planned anything yet - all they have done is talk, talk and talk some more.
By now, in the 13 years of Labour, with 10 years of "boom", we should have multiple new nuclear stations in this country - instead we have no new ones, and no new ones for at least 20 years (the major component manufacturers have their order books filled for over 10 years by the Chinese and Indians)