Have a read of a fantastic book 'without hot air' free online by Professor David Mackay of Cambridge University.
David MacKay: Sustainable Energy - without the hot air: Home
The book is a fair analysis of the real choices that face us regarding renewable energy.
Reading this it is clear that the principle of pumped storage has considerable merit and relevance to making real use of wind power. It is also clear that the scale of the challenge is massive and hyperbole from SOI claiming energy independence within 5 years does not help their case. To even get to 20-40% use will be a major achievement.
What we really need is a real proposal from SOI with real costs and also clearly stating where all the wind turbines are to be located to make sense of their proposal.
We then as a nation need to decide whether or not to go this route and we also need to look seriously at other options dispassionately (nuclear etc..) and make sense of a future where fossil fuel use will have to decline. Personally I would prefer both nuclear and wind/pumped storage as together in my view this would give a proper spread of energy sources.