errr i think you misunderstood me
the idea of running dry if that there is nothing to replenish what you take.... so.... if you are taking a finite resource it will be 'running dry'........ I didnt give any sort of opinion on how long this will take, there are many reports saying different thing, it depends which you chose to believe. As you very well stated that prediction is at current usage..... energy demand is increasing substansially!
so yeah i wasnt being alarmist its just a turn of phrase.
Renewable energy is viable, get in touch with a large scale wind company and ask for their finances. The issue is needing up front capital!!!! but once build they will pay back quickly. they are a well established technology and are reliable. you cant use terms like value for money as the comparision is with fossil fuel technologies which have many many associated costs which are never shown..... transport of the fuel etc..... not to mention trying to quantify environmental costs.