Seven Sustainable Technologies | John Michael Greer

Jan. 14, 2014 (Archdruid Report) -- Last week’s post on the contemporary culture of apocalypse fandom was also, more broadly, about the increasingly frantic attempts being made to ignore the future that’s looming ahead of us.

Believing that the world as we know it is about to crash into ruin, popular as it is, is only one of several strategies put to work in those attempts. There’s also the claim that we can keep industrial civilization going on renewable energy sources, the claim that a finite planet can somehow contain an infinite supply of cheap fossil fuel -- well, those of my readers who know their way around today’s nonconversation about energy and the future will be all too familiar with the 31 flavors of denial.

It’s ironic, though predictable, that these claims have been repeated ever more loudly as the evidence for a less comfortable view of things has mounted up. Most recently, for example, a thorough study of the Spanish solar energy program by Pedro Prieto and Charles A.S. Hall has worked out the net energy of large-scale solar photovoltaic systems on the basis of real-world data. It’s not pleasant reading if you happen to believe that today’s lifestyles can be supported on sunlight; they calculate that the energy return on energy invested (EROEI) of Spain’s solar energy sector works out to 2.48 -- about a third of the figure suggested by less comprehensive estimates.

The Prieto/Hall study has already come in for criticism, some of it reasonable, some of it less so. A crucial point, though, has been left out of most of the resulting discussions. According to best current estimates, the EROEI needed to sustain an industrial civilization of any kind is somewhere between 10 and 12; according to most other calculations -- leaving out the optimistic estimates being circulated by solar promoters as sales pitches -- the EROEI of large scale solar photovoltaic systems comes in between 8 and 9. Even if Prieto and Hall are dead wrong, in other words, the energy return from solar PV isn’t high enough to support the kind of industrial system needed to manufacture and maintain solar PV. If they’re right, or if the actual figure falls between their estimate and those of the optimists, the point’s even harder to dodge.

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