I've put a bunch of effort on this forum into discussing what I consider one of the most important issues facing the US and mankind in general: where to get/how to use energy. I'd like to discuss the history of and projections for future energy use. Here's an article with some charts. Unfortunately, they only go back about 60 years, but they provide a good start. http://wilcoxen.maxwell.insightworks.com/pages/804.html My feeling is that the energy situation is mitigated somewhat by us reaching a bit of a development plateau, when it comes to energy. Prior to the 20th century, what was our biggest energy need? Heat? The 20th century saw several major developments that increased our energy consumption: transportation, air conditioning and computers. Transportation: by the turn of the century, commercial transportation had already switched to fuel-powered, with steam ships and trains. But the first half of the 20th century saw essentially every household in the US getting a car. And then air travel took off. There wasn't much air conditioning before the second half of the 20th century, but in that timeframe it became ubiquitous commercially and residentially. Computers, of course, took off in the mid-1980s and not only did the computers themselves proliferate but their energy consumption grew as well. Today, their energy consumption has plateaued since manufacturers are loath to provide water cooling or refrigeration for personal computers. These three sectors represent a huge fraction of our energy usage (how much exactly, I'll have to work on qantifying) and they have all plateaued and may in fact see significant drops in the near future as efficiency becomes more important. One measure of this can be seen in the "energy per dollar of GDP" graph, where a dollar of gdp today requires half the energy it did 60 years ago. The total energy consumption graph may reflect my 3 big consumers above. Total consumption stagnated from about '71 to '86. Now that may be partly due to the economy, but I bet a large part is also due to the lack of growth in the areas I highlighted. By the late '80s, though, computers started getting big and energy usage was growing again. Now, it may be leveling off (according to wiki, as of 2005 it was still about 100 quad). All of the major users I listed above were predictable. Full market penetration took several decades at least, but in 1982 (for example), it was forseeable that in 20 years, there'd be more PCs than people in the US. In the 19-teens, when rich people had cars, it was forseeable that eventually everyone would. In the 1930s and '40s when rich people could fly it was forseeable that eventually everyone would. Etc, etc. Today, there aren't any such energy hogging technologies on the horizon and I believe that signals a development plateau where energy use is concerned. So what does this mean for our energy situation? It gives hope that exponential growth in energy consumption isn't going to come back. It makes the issue easier to deal with because it means that planning for the future includes mostly just reallocating how energy is produced, not also finding ways to produce exponentially more. Though I think politics is still in the way of the proper solutions (and that's an issue for another thread...), I think from a scientific/engineering standpoint our energy issues are not as severe as I had feared say, 5 years ago when I started the sticky'd thread about our energy situation.