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Energy Usage Growth - History and Future

  1. Jan 17, 2010 #1


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    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.
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  3. Jan 17, 2010 #2


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    Hi Russ,
    Interesting about the energy situation and "development plateau" as you call it. That's a nice explanation you provided regarding why energy consumption might level off. I can't say I've given it much thought, though I've often considered the production of energy to be one of the more important issues facing engineers.

    Reading through your OP, and looking at the graphs provided on the link, the question that came to mind was how much energy per capita is being used? Has it continued to rise? Level off? Go down? I found a graph http://www.google.com/publicdata?ds...=energy+consumption+per+capita+united+states" that shows that in the US, it has leveled off since the 1970's.

    What this means for our energy situation seems fairly obvious. The plateau is measurable and has existed for a few decades in the US. However, there are many more people worldwide who are using a tiny fraction of the energy that people in the US are using. And those people want to have a standard of living equal to the US, with energy consumption being a part of that. So it is in those developing countries that we'll find the exponential growth of energy. But in the end, we can probably assume that the per capita consumption of energy in those countries shouldn't exceed that in the US today, and should even be less given improvements in efficiency. That's still a lot of energy sources that need to be developed, but even in the US, there are legitimate plans to provide all the energy needs from renewable sources such as wind, solar and other means.
    Last edited by a moderator: Apr 24, 2017
  4. Jan 19, 2010 #3
    There are some nice charts at

    https://publicaffairs.llnl.gov/news/energy/energy.html [Broken]

    that show energy production and use 'flowpaths.' While not intended for predicting the future, they are an interesting representation of current use. They show production, use, and energy rejection graphically. The big picture all on one page.
    Last edited by a moderator: May 4, 2017
  5. Jan 25, 2010 #4


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    More comprehensive list of US energy indicators here from the EIA, back to 1950 through 2006 or 2008:

    Interestingly, US spending per capita on energy doubled from 1970 to 1980, doubled again from 1995 to 2006 in nominal, non-inflation adjusted dollars.
  6. Jan 25, 2010 #5


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    There will likely be a few like http://www.google.com/publicdata?ds...ARE:QAT&tstart=-315619200000&tunit=Y&tlen=46" that, given the income, will exceed current US consumption.
    Last edited by a moderator: Apr 24, 2017
  7. Jan 25, 2010 #6


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    I agree with this conclusion except in the area of transportation energy costs, due to the reliance on oil imports. China and India are growing fast, but I expect they'll be largely self sufficient for electric power and heating. For transportation, they and everyone else will need to import oil, driving the price up faster than otherwise robust economies can handle. Absent some big changes in transportation energy methods or supplies, I'll predict the US will see $7/gallon gasoline before you can make the next 5 year update of the History and Future of Energy.

    (I think most everyone knows my preference for a solution. :wink:)
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