As a physicist, my belief is that one of the reasons that intelligent energy policies have not gained sufficient traction is that we are allowing those with political agendas (vs scientists) to define some key energy terms. And as a golfer, I know that a wager can be won or lost at the first tee — where the terms and conditions are agreed on.
Outside of “fiscal responsibility” probably the most significant misused concept that we have unwittingly gone along with is the term “renewable energy”. Giving some critical thought to this moniker is no academic matter, as the majority members of the U.S. Senate’s Energy Committee are currently pushing for a national Renewable Portfolio Standard (RPS), or what is now called the Renewable Electrical Standard (RES). Their decision as to what is a “renewable” will have profound technical, economic and environmental consequences on the United States.
To my knowledge there is no “official” definition of this bandied about term. When asked, the meanings proffered vary quite a bit, but the key difference between a renewable and non-renewable is usually the rate of replenishment. “Renewable is an energy resource that is replaced in a reasonable amount of time (our lifetime, our children’s lifetime),” the thinking goes.
Such a word as “reasonable” is subjective — not scientific. Who determines what s a reasonable amount of time, and what is it: 100 years? 500 years? 1,000 years? 2,500 years? Longer?
The reason the definition of renewable is focused on time, derives from the concern that we may exhaust some electrical energy sources, relatively soon. But how much is enough to have? For instance, if we have 100 or 250 years of some particular fuel, would the replenishment rate really be that important?
Clearly, within the next 100 years of use, there will be some profound changes made regarding the efficiency and applications of said fuel’s implementation—in ways we have little understanding of today.
Look at the well-reasoned expectations that were had in 1950 about what would happen in year 2000. The message is that almost ALL of the best guesses were wrong. In the same vein, prior technology predictions by experts (like Einstein) have also proven to be significantly off the mark. Who among us will stand to say that we
have a better understanding of technology than did Einstein?
In that light, let’s look at the case for nuclear being “renewable.” First we should answer how much longer will our nuclear fuel supply last. Consider:
a) This source says: “The Organization for Economic Cooperation and Development (OECD) and the International Atomic Energy Agency (IAEA) in 2008 jointly produced a report saying that uranium resources are adequate to meet nuclear energy needs for at least the next 100 years at present consumption levels. More efficient fast reactors could extend that period to more than 2,500 years.”
It is absurd to say that a 2,500 year supply doesn’t qualify this as renewable.
b) In addition, there are several proven alternatives to uranium as a source. One example is Thorium (which is much more plentiful than uranium). [Read the end of this for a superior discussion about “The Sustainability of Mineral Resources” (and specifically uranium).
c) Bernard Cohen (Professor Emeritus of Physics at Pittsburgh University) has stated that breeder reactors have enough raw material energy source to last us over a Billion years. That’s Billion with a “B”.
When considering these sample facts, an important thing to keep in mind is this quotation from some scientists at an excellent University of Michigan site: “Only 40 years ago, nuclear energy was an exotic, futuristic technology, the subject of experimentation and far fetched ideas.”
Hard as it might seem to believe, most of this nuclear development has occurred in just the tiny space of 50± years — so having any fuel supply that lasts 100± years could cover an enormous amount of new development.
Some definitions of “Renewable” include a reference to “power derived from natural sources” (e.g. here). Of course that is amusingly non-descriptive since essentially all sources of electrical power are based on natural materials, and that includes nuclear. To read more about this I’d strongly recommend Bill Tucker’s excellent book Terrestrial Energy, or the more condensed discussion he wrote here.
Another factor sometimes appearing in the definition of “Renewable” is a reference to a power source’s ability to reduce CO2 (i.e. to be a “clean” source). That same University of Michigan site (above) has this very informative graph about how (worldwide) we have been able to reduce CO2 since 1973.
Now, for the sake of comparison, let’s quickly look at the flip side of this question, at the poster child for renewables: wind energy. The indisputable fact is that an indispensable part of wind power electricity production is the requirement of LARGE amounts of land. For instance, best estimates are that wind energy requires more than a thousand times the land that nuclear does, to generate the equivalent amount of 24/7 power.
BUT, that essential element of wind energy generation (land) is not renewable by anyone’s standards as it is not “replaced in a reasonable amount of time.” Before a source is labeled as “renewable” shouldn’t ALL of its major components be renewable? Otherwise, it would be like having all the materials to assemble a car, but no tires.
The evidence says that we will run out of appropriate U.S. land for industrial wind energy before we run out of fossil fuel for electrical power sources. So considering this information, which is the true renewable: wind energy or nuclear power?
First, thanks for your opinion. Second, I’m no expert in this. That said, here is a tentative description of my opinion. Intuitively, I would argue “nuclear is less renewable than wind,” though, nuclear too is renewable, I think (if uranium can be naturally rebuilt). Oil certainly is renewable.
I just had a kebab for lunch and was thinking about your post which I have read before lunch. What follows should be a summary. What if we relate “renewable” with “entropy’s arrow.” Please correct me (as a physicist!), spontaneous processes move from low to high entropy states (i.e. high concentrations to low concentrations). Nuclear is (economically) interesting for us, because it is highly concentrated energy source. By converting it to other energy forms, we increase entropy.
So, what if we think of “renewable” as an energy source’s rate to reverse this process, to point entropy’s arrow in the other direction?
So, in principle, most energy sources are probably renewable. Some are just better then others in the sense that “something” or “somebody” makes sure to reverse entropy’s arrow of the source faster.
Example, nuclear, uranium. If we convert X units of energy, the process will increase entropy, we get electricity, and it will take Y units of time for “something” (e.g. Earth) to reverse this process, i.e. replentish our X units of energy in form of uranium.
Example, solar. We convert the same X units of energy, increase entropy by conversion to electricity. It will take Z units of time for something (e.g. the sun) to reverse this process.
Could it be that Z < Y?, i.e. the case of solar is faster in reversing entropy’s arrow, and so “more renewable” than nuclear?
Just my two cents, during a siesta after my delicious kebab,
[…] nuclear power, from the Center for American Progress. What
There are several (my last count was 29) states and numerous countries that have “official” definitions of the term renewable–BUT NOT ONE OF THEM IS SAME AS ANY OTHER.
I’m responding on an empty stomach, so it might not be as elegant as your comments.
My underlying theme in all my articles is that science, not politics, should be the basis for our decisions.
The term “renewable” has been politically hijacked to serve other agendas. In your first paragraph you provide your “intuitive” view.
This is often where even well-intentioned people go astray. Wind power (for instance) intuitively seems like a good idea. The scientific evidence says that it is anything but.
Message: GO BEYOND INTUITIVE!
I’ll have to ruminate about your entropy observation. Maybe with a Genesee Cream Ale.
BTW, Tom made an excellent point about the arbitrariness of the term “renewable” considering that 29 states don’t have any agreement.
I was shocked to discover that hydro power is NOT considered to be a renewable under the terms of RES:
Such logic demonstrates that thes policy actions being considered have little or nothing to do with the environment no matter what the rhetoric.
Thanks for your reply. I’m indeed new to the environmental field, though perhaps I’ll have a chance to get a bit more into the science soon. My first reaction to your point “scientific evidence says that [wind] is anything but [a good idea]” is: along which dimensions?
I would like to develop a thought, which perhaps explains what I mean by “along which dimensions.” According to , in the US there is a 1.55 x 10exp17 Btu / year flow of wind (and a 7.7 x 10exp18 Btu storage of oil). The problem of wind (and solar), to me, doesn’t seem that it wouldn’t make sense to harness the energy (there is *a lot* of it) but that it’s power density is low which means it is not concentrated (low entropy) and hence (economically) tricky to deliver (to users). And here comes my question “along which dimension(s) is it all but a good idea?” As far as I undersand it, it’s not a bad idea to tap wind because of it’s Btu flow / year, this seems rather attractive. It might be a bad idea, because of it’s low power density, which might make it w.r.t. the state of the art in technology an overall bad idea. I don’t know.
Regarding the arbitraries of the definitions. I absolutely agree with all of you, to have a standard definition not only shows maturity of a field but is, I think, generally a good thing. However, I don’t think, we can trash the entire discussion, because we don’t have an agreement in defining the term “renewable.” As an example, think of the science of complexity. There is no agreement, AFAIK, on what complexity is. We have an intuitive definition, some agree on some characteristics of complex systems, but there isn’t consensus. Does this detract anything from the reality of the problem? Should we stop to think, discuss and research complex systems because there is no consensus on its definition? I don’t think so.
OK, sorry, I might be a bit OT here.
Thanks for reading.
 Kaufmann and Cleveland. Environmental Science.
Not sure what you meant by “trashing the discussion” as I am not doing or advocating any such thing. I am refining the definition to include something that makes scientific sense.
Re why wind is a bad idea: all new alternatives should be independently and objectively assessed to verify that they are technically, economically and environmentally sound. Wind power fails on all three counts. To see more, check out my online presentation “http://www.slideshare.net/JohnDroz/energy-presentationkey-presentation”.
I don’t like the term “renewable” anyway-to brand nuclear with it would be an insult to nuclear.
I think it is fair to say that from a physical, natural-science perspective, minerals are nonrenewable–they cannot be synthetically reproduced by man–or by nature in human time frames.
And from such a physical viewpoint, there can be a fixity estimate from which production/consumption can be subtracted.
But in terms of economics, business, and public policy, fixity/depletion is not a useful way to view the mineral world. In fact, business people and policymakers who see the world in terms of fixity/depletion have been burned time and again.
In the social world, mineral resources are replenished in human time frames. Thus the renewable/nonrenewable distinction must be abandoned as a macro concept. (On the micro level, fields and wells deplete and reach their economic limit.) So the glass is not half full or half empty–there is no glass!
For a fuller treatment of this view, see my essay “Resourceship: An Austrian Theory of Mineral Resources,” at
Sorry, I mean the community shouldn’t stop searching for a definition we can agree on and/or in any way hinder research on non-/less-polluting energy sources (included wind) because there is no consensus on the term.
I agree with you that an energy source should be verified for its technical, economical and environmental soundness. Though, I’m afraid, it hasn’t been done for most of the energy sources we currently use. (Why I say this? Example oil: because of gov. subsidies I question the economical dimension, because of pollution the environmental. Example nuclear: AFAIK, there is no consensus yet on how to store nuclear waste; the risk/cost to store nuclear for thousands of years does, at least for me, question its economical soundness. I have no answers to such questions, perhaps others have.)
Thanks for the link, I’ll check out your slides (slideshare is currently down for maintenance …)
[…] nuclear power, from the Center for American Progress. What’s not renewable about nuclear power?, asks Master Resource—by some estimates, fuel supplies could last 2,500 […]
There’s no such thing as renewable energy. Any interesting use of energy increase the entropy of the Universe. Unseen by solar and wind advocates the sun destroys 4 million tonnes of mass each second by fusing hundreds of millions of tonnes of hydrogen into helium to create the diffuse and unreliable streams of energy here on Earth they wish to tap; nothing is renewed here.
Geothermal energy taps the heat from the steady and inexorable radioactive decay of thorium-232, uranium-235, uranium-238, potassium-40 and their daughter products. These elements were created in dying stars during the intense heat and neutron flux following a few minutes after a super-nova; there nothing renewable here.
Nuclear reactors takes these same elements(save for potassium-40) and concentrate them and then split them into two unequally sized daughter products in a process called neutron-induced fission. There’s certainly nothing renewable here either, but it does squeze a little bit more energy out of a heavy atom than waiting for it to decay into lead.
Coal, oil and natural gas are biomass energy. They’ve been sequestered for so long that they’ve been chemically converted into slightly different fuels but the energy came from fusion in the sun. They’re a little less polluting than fresh biomass, but they release a lot of CO2 that has been sequestered in the Earth and we have every reason to believe that putting it back into the atmosphere will radically alter the Earths climate. Certainly nothing renewable here.
It’s like an ostrich sticking it’s head in the sand(except real ostriches aren’t dumb enough to do that, only fictional ones); if the fuel isn’t visibly being burnt directly by humans, no fuel is consumed and the process is ‘renewable’. Those selling natural gas have a keen interest in steering public policy and advocating ‘renewables’ due to their complete inabillity to operate in a post-carbon grid; the storage and transmission problems are simply insurmountable without natural gas, ensuring a steady demand. Enron and shell, both with large stakes in natural gas, advocated/advocates the use of ‘renewables’ and they do so for reasons of self-interest.
Renewable, just like natural, are buzz-words that are purposely left illdefined and vague. They have no real purpose apart from engendering a good feeling in your stomach.