Re: @45RPM
Ignoring the manufacturing energy cost of everything we import (which is basically everything we use, from solar panels to TVs), as well as industrial use, the UK uses 100 million tonnes of oil equivalent per year for domestic and transportation needs, with one "tonne of oil equivalent" containing around 11MWh. Assuming that all of that needs moving to "CO2 neutral" sources, we need something like 1000TWh of energy per year.
Also assuming an avarage output of 5W/sqm, or 5MW/sq km, for solar (the reported value for a solar farm in Bavaria), you'd get 44GWh per year per sq km of solar. You'd only need to cover 1/10th of the UK in solar panels for this to work!
Solar panels have an energy payback time of around 2 years, which means we can easily estimate how much power it would take to manufacture that 23,000 sq km of panels - it's just twice the total annual output, or 2,000TWh. I'm sure China will gladly burn the approx. 280 million tonnes of coal needed to manufacture that lot, it's only 0.2% of their reserves. Obviously, once we covered 1/10th of the UK in solar panels, we'd have to dedicate a fairly large amount of that energy output to manufacturing new solar panels, as they only last a decade or two.
As my somewhat flippant back-of-the-envelope maths shows, "a nice mix of energy sources and reducing the standby power of our devices" does not even come close to a fraction of the scale of the problem.
Biting the hand that feeds IT
