Expanding the Definition of Renewable
I often cringe at the simplistic associations words pick up. "Natural" is totally benign. "Renewable" usually means solar and wind power. I could continue to make such associations, positive and negative, with lots of words we see and use frequently--organic, ecological, sustainable, GMOs, nuclear, fossil.
As I have noted previously, particularly with respect to nuclear power, the truth is usually more complex. In particular, I have pointed out numerous times that the "renewability" of solar and wind power applies only to the direct energy source--the sun and the wind. Actually getting the energy out of these sources on the scale required for modern society requires, among other things, materials such as rare earths that are not in infinite supply.
I was delighted to find an article recently that expanded my vision. While I have been focusing only on the non-renewable elements of solar and wind energy production, James Conca, who writes for Forbes, recently looked at a a future where uranium might effectively become a renewable energy source.
He was talking about the potential to extract uranium from seawater. Admittedly, this is a technology that is not here today, so perhaps this is not only a different side of the picture than I've been focusing on, but it also reflects a different period of time. Therefore, as with all projections about technologies that have not yet been built and tested, we have to be careful about how much we credit it.
As Jim points out, there is a lot of ocean, and the continued leaching and weathering of rocks will replenish whatever we extract from the seas. Perhaps the biggest sticking point is whether this process will be economical. One guesses that there is a good chance that it will be economical, since the price of fuel is not a major component of the price of running a nuclear power plant. However, this does remain to be proven.
Likewise, of course, proponents of solar and wind power will correctly point out that costs have come down dramatically in recent years, and that there is research underway on methods to improve the efficiency of solar cells, develop better energy storage options, and perhaps find materials that are in greater supply. Again, we are talking about something in the research phase, and we do not know today whether the most optimistic of the projections will be realized.
The truth is that advances are likely in all energy technologies, but it is sometimes difficult to know how to incorporate such advanced technologies into our planning about the future. We can't count on every predicted advance to be realized, but we can't count everything out, either.
But Jim's article did get me to thinking about the way the word "renewable" is used in talking about energy today. I have long chafed at the use of the word renewable for energy technologies because the term doesn't acknowledge the reality that non-renewable materials are used to extract the renewable energy. Now, I will also chafe at the fact that the term doesn't recognize the fact that the total supply of uranium potentially makes nuclear energy as renewable as solar and wind.
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