I guess the 20 Mw of installed PV were also used to produce the wind turbines? And those cranes used for the installation I am sure were using only bio-diesel, along with the plug in electric trucks were just sitting around waiting to deliver it all to site.

Of course we have been able to amke shiny metal things for a few thousand years but you seem to think aiming them is easy. It is not easy now, even with our modern control systems to line up thousands of highly polished mirrors ot concetrate enough sunlight on one spot to capture it. Accurately lining up these things requires some pretty hi tech control systems, X and Y axis servo motors for each mirror and an army of cleaners to keep all the dust, grime, bird shit and other crap off them so that they keep working at the design efficiency. Any dulling of the polished surface will reduce the effectiveness considerably as the sunlight scatters in all directions rather than the predictable angles required.

As far as PV goes, this is great for isolated, small scale, low deamnd installations. Even if isolated means your suburban house with a 20KW system on the roof, it is still of limited value to industry , even if you do supply the grid. The power grid is currently designed for a one flow of power. It is not equipped to upload massive amounts of unregulated, PV generated power from every household that wants to do their bit. You may be able to share a bit with your neighbours within the same local distribution grid, but you are not going to supply anything to the aluminimu smelter that is turning out new wind turbine blades. The smelter and other heavy industries need high security power supplies to stay in business. You can't just turn some of these things off, becuase the wind stops or the clouds roll in.

The most reliable form of solar energy conversion is hydro-electricity. If we could combine itermittent wind and other solar technologies to pump water up hill rather than rely on the rain to get it there, we will ahve gone a long way to closing the loop. The biggest problem is having big enough storages to create the scale necessary to keep our curretn industrial apparatus all going.

But hey, if you've got all th answers, theres no shortage of suckers out there waiting to invest.