General comments

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srbarbour's picture
Status: Silver Member (Offline)
Joined: Aug 23 2008
Posts: 148
General comments

Excellent chapter, Chris. What follows is more a run through rather than complaints. No, even better, think of them as side notes.

Consumption of resources: It is important to note that many resources, like copper or steel, are quite unlike oil. Where oil, as an energy resource at least, is truly 'consumed' mined iron and copper remain 'intact' to be reused and recycled. Indeed, most of these metals are recycled at incredibly high percentages because it is much cheaper to recycle them than to extract more. This deviation is quite important because, where as with oil or coal we have to continually work in order to 'tread water', with iron or copper the huge costs of extraction are mostly relevant because of continuous expansion.

Hence, the consequences of depletion are quite a bit milder.

Uranium Mining: While uranium is currently being consumed quite quickly, there are two things to note about nuclear energy:

1) Nuclear energy is about 6-7 magnitudes more energy dense than most chemical energies. Meaning it can be several magnitudes harder to extract and still provide plenty of energy.

2) Current reactors use uranium in a very inefficient manner. Consider, as we currently use uranium, reserves have been estimated as being able to fuel the entire world for about 100 years. However, if Uranium is used efficiently this number expands to as much as 10,000 years.

Unexpectedly, this shift in usage is very easy to accomplish, as it essentially makes use of existing nuclear reactions -- specifically the neturons produced -- to 'up breed' existing Uranium-238 into Plutonium. If ever you read an old '50's' article about the infinite promise of nuclear energy a plutonium based nuclear energy system is what they were imagining.. Why didn't it happen? *cough* Nuclear Proliferation *cough*.

There was quite a good Scientific American article -- that appears to be the one -- on the subject not too many years back. It is highly recommended reading for anyone really interested in the potential of nuclear power.

As a final side note, while I understand saying 'energy can't grow'. It would probably be more accurate to say 'energy must grow differently'. There is quite a bit of renewable energy out there, and other sources can also help tide us over. However, if we want to escape the clutches of (reasonably) finite energy sources, we are going to have to put our wallets down. That and likely swallow a lower short-term or even long-term economic growth rate (due to lower energy-investment to return ratios).

Once again, an excellent chapter Chris.



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