However,
he doesn't pay much attention to renewables, other than saying CSP is worth
looking at. His data shows that biofuels and shale gas are all hopeless in
EROEI terms, as is PV solar, well below his EROEI cut off point for
profitability of 15, and wind is not much better- he puts it a just under 15.
There
are higher estimates. For example, Gagnon’s study 'Civilisation and energy
payback' in Energy Policy 36 (2008) 3317-3322 and Danny Harveys excellent work
on EROEIs. Gagnon quotes
EROEIs for wind power, with 35% load factors, of ~18 for Offshore and 34 for
Onshore. Harvey’s 2010 book ‘Carbon Free Energy Supply’ ( Earthscan) , using
more recent data, puts the EROEI for wind at 40-80, and it’s likely they will
improve on that with new technology.
It’s
worth noting however that hydro does much better, with EROEIs of 200 or more,
due to the long life of the plant. Nothing else can compare. Harvey puts CSP at
8-40. But PV is now getting better (Harvey puts it at 10-25) with new less
energy intensive cell technology, and wave and tidal stream power may follow
the path of wind to lower EROEIs, while nuclear will get even worse, as lower
grade fuel has to be processed. Gagnon puts current PWRs at 14-16, while Harvey
quotes 17-19 for the current world average uranium ore grade of 0.2 - 0.3%, but
for an ore grade of 0.01%, it drops to 5.6 for underground mining and to 3.2%
for open pit mining, and could be as low as 2 for in situ leaching techniques. So
nuclear could become even worse than coal which Harvey quotes as 5-6.7 and even
gas plants, at 2.2. Renewables can do much better than that, not least since
they don’t need fuel. They offer power sources for a new and sustainable
economic and energy system. If we are to return to some sort of growth,
that may be where it will be. So maybe our banker friend, and the rest of us,
can breath easier. www.tullettprebon.com/strategyinsights/index.aspx
Tim
Morgan is not the first to warn of industrial and economic collapse due
to falling EROEIs. See for example 'Energy and the Wealth of Nations’, Charles
A. S. Hall and Kent A. Klitgaard, Springer, 2011. And of course Barry Commoner
said it all in the 1970s, though he put it in terms of capitalism running out
of capital faced with the increasing cost of energy technology.
Proponents of simpler conserver lifestyles, like Ted Trainer, who don’t
see renewables being able to support anything like current ‘Western’ living
standard, also say similar things. And it certainly wouldn’t hurt (much) to
adopt a more sustainable approach to consumption, as Tim Jackson has argued in
his seminal ‘Prosperity without
Growth’.
Some
say this will be forced on us. For example in his 2007 World Energy and
Population (WEAP) blog report, Paul Chefurcha said that oil would peak round
about now, while gas, and then coal, would peak around 2025. Shale gas and oil
may extend that a little, but, more interestingly, he also claims that nuclear
won’t get off and running and although renewables will, their growth will stall
and collapse around 2090 or so, since there wont be enough fossil/ nuclear
energy or the high level of technology and manufacturing capacity needed to
sustain expansion. The result is further societal and population collapse.
This
particular doom scenario seems unlikely, or, rather, unnecessary. If we invest our remaining fossil (and
fissile) fuel in building up renewables capacity, we will create a base for
further renewables growth, up to maybe a sustainable steady state, which will
then only need small energy inputs for upgrades and replacement. However it
could also provide a surplus, to allow for more growth, if that’s what we
want/need, up to the final planetary limit of renewable energy availability,
which is some way off, even given land use constraints. There is an awful lot of
desert for CSP/CPV and sea for offshore wind, wave and tidal. The only (!) uncertainty is- will we
invest fossil energy in this, or just burn it off, for no long-term
benefit. Chefulka is not
confident. He thinks we are doomed
by our willful short termism and greed for more. Certainly, as the WEAP study
makes clear, and as the Optimum
Population Trust also always says, what would help, is less economic growth
expectations, or at least less people! www.paulchefurka.ca/WEAP/WEAP.html
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