In the preceding posts, I have done some “back-of-the-envelope” calculations of how much land would be required to generate enough electricity using wind and solar energy to cover total energy consumption in the USA or in Missouri. I found that to cover total United States energy consumption would require wind farms on land equal to the size of South Carolina, or solar farms on land equal to almost the size of Texas. Alternatively, it you put solar panels on rooftops, it would require roughly six time as much roof space as exists in the entire country. To cover Missouri’s energy consumption would require wind farms on land equal to the size of Iron County, or solar farms on land equal to about 7% of the state.
I didn’t consider the need for storage, redundancy, peak demand, additional capacity to cover times when the wind wasn’t blowing or the sun wasn’t shining, or losses during delivery of the electricity to customers. All of this means that my estimates are bare minimums, and the actual land required would be larger. How much more? I don’t know.
The International Panel on Climate Change has estimated that we need to reduce GHG emissions 41-72% by 2050 in order to avoid the worst effects of climate change. If the United States were to attempt to meet that goal entirely through converting to renewable energy, then only 41-72% of the land I estimated would be required, plus the extra land required for the reasons cited above. Perhaps the end result would be in the rough vicinity of my estimates.
But the United States doesn’t have to make renewable energy the only possible way of reaching the goal. Other strategies might (and probably should) include reducing how much energy we consume and increasing the efficiency of the energy we do use. These are obvious strategies, they are far and away the most cost-effective ways of reducing GHG emissions, and there are no technological hurdles stopping us from getting started. The only thing stopping us is our refusal to do it. Like smokers with lung cancer who still smoke, we continue to emit GHGs despite their harmful effects.
Two other strategies are also possible, though significantly more controversial: nuclear power and population reduction. Nuclear power is one of the most efficient, most reliable forms of generating electricity that has been invented. It has virtually no GHG emissions. The problem is that, in its brief history, every 20-30 years something somewhere has gone spectacularly wrong, and the consequences have been devastating. Entire regions have been made uninhabitable, the costs have been in the hundreds of billions of dollars, and remediation has been virtually impossible. The Ukraine is still working to seal-off the Chernobyl Generating Station, and that accident was 30 years ago. Nuclear power seems to me something we can’t live without, but something we can’t live with, either.
The other strategy is population reduction. I personally believe that in 100 years human population will be significantly less than it is today. Whether that will come voluntarily or involuntarily, I don’t know. It is seems to be common wisdom these days that Malthus and Paul Ehrlich were completely wrong, and that Malthusian sorts of analyses are all off base. I don’t think so. Malthus and Ehrlich were spectacularly wrong in the specifics of their predictions; the dynamics of population and the world’s capacity to support life were influenced by factors they did not understand. The fundamental logic behind their analyses, however, is that you cannot infinitely increase population in a world with finite limits. Duh! That still seems cogent to me. People use resources and generate waste and pollution. It all puts the earth under stress, and the results show up in hundreds of ways that are plain to see if one only reads the newspapers. We have shown remarkable ingenuity in stringing this along for much longer than Malthus and Ehrlich thought we could. How long we can continue to do so, I don’t know. There are numerous important ecological systems that appear to be nearing tipping points, and unless we take the stress off them, sooner or later they are likely to start collapsing. Or so I believe.
Our population could be reduced through wars, famines, or plagues. These are the historical ways in which human population has been reduced, and these are the methods that nature uses to reduce population among other animals. These would all be terrible disasters, and any sane person would hate to see such a thing happen to the human race.
Planned population reduction has never been tried for an extended period on a global, or even a nation-wide basis. It comes with serious economic and demographic problems that people the world over have been unwilling to face. But they are better than population reduction through war, famine, or plague. I personally believe that if we don’t do this, then nature will do it to us. I don’t look forward to that time, either for myself, or for my child, or for my child’s children.
Climate change is just one of the stresses. Others could be named, such as changes to the ocean, desertification, water scarcity, or the mass extinction of species that is currently occurring. But the last few posts have been on renewable energy, so I’ll end with this:
Reducing GHG emissions through the use of renewable energy would be a big, expensive task. We would have to cover large areas of the country, and we would have to solve a number of thorny technical problems. But in terms of the land available, it is possible. We could do it, especially if we also used the other strategies like reducing consumption and increasing efficiency.
Addendum: This post was written in early August. On October 3, the New York Times published an article saying that this year the carbon dioxide concentration of the atmosphere at Mauna Loa Observatory was measured at greater than 400 ppm., and is likely to remain above 400 ppm. for the immediate future. While 400 ppm. is not a catastrophic tipping point, it is a milestone. Those who had hoped to limit the effects of climate change had hoped to keep the carbon dioxide level below 400 ppm., or at least delay (by decades) the day it was exceeded. Well, we have blown by the milestone faster than almost anybody anticipated. It is not a tipping point, but it is a sign that the world has yet to take climate change seriously, and has yet to make the changes needed to head off its worst effects.
Chernobyl Disaster. Wikipedia. Viewed online 8/4/16 at https://en.wikipedia.org/wiki/Chernobyl_disaster#Economic_and_political_consequences.
Diamond, Jared. 2005. Collapse: How Societies Choose to Fail or Succeed. New York: Viking.
Ehrich, Paul. 1968. The Population Bomb. Sierra Club/Ballantine Books.
IPCC, 2014: Climate Change 2014: Mitigation of Climate Change. Contribution of Working Group III to the Fifth Assessment Report of the Intergovernmental Panel on Climate Change [Edenhofer, O., R. Pichs-Madruga, Y. Sokona, E. Farahani, S. Kadner, K. Seyboth, A. Adler, I. Baum, S. Brunner, P. Eickemeier, B. Kriemann, J. Savolainen, S. Schlömer, C. von Stechow, T. Zwickel and J.C. Minx (eds.)]. Cambridge University Press, Cambridge, United Kingdom and New York, NY, USA. Table SPM.1.
Malthus, Thomas. 1789. An Essay on the Principle of Population. Public domain, viewed 8/4/16 at the website of the Electronic Scholarly Publishing Project, http://www.esp.org/books/malthus/population/malthus.pdf.