On the renewable energy front, here is a look at some data from The Economist on wind energy around the world:
(From the Economist): "THE first wind farms sprouted in California in the early 1980s, thanks to generous tax credits. Today's machines typically have a capacity of 1.5-2.5 megawatts, or 30 to 50 times that of early turbines. Although wind generates only about 1% of all electricity globally, it provides a respectable portion in several European countries: 20% in Denmark, 10% in Spain and about 7% in Germany. Capacity in America jumped by 45% last year to reach nearly 17 gigawatts (GW). China has nearly doubled its capacity every year since 2004. Globally, wind power installations are expected to triple from 94GW at the end of 2007 to nearly 290GW in 2012, according to BTM Consult, a Danish market-research firm."
click to enlarge
Graphic courtesy of the Economist
When you look at the % of total energy production that countries like Denmark and Spain are able to produce via wind energy, it does give one hope that similar (if not greater) percentages can be achieved here. Overall I think the key to achieving feats such as this is the understanding that it's a slow multi-year evolution and we'll probably need to use multiple sources of renewable energy to meet our needs, as opposed to some of the current thinking that seems to be along the lines of: "it's too hard, why bother?", "it will never work", "coal works now", etc.
Better yet, at the end of the day the only thing that matters is that our current energy sources are running out, so we have no choice but to begin the transition towards renewable energy sources now.
The Economist.com: "Daily Chart: Blow Hard" -- December 5, 2008.