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0 pointsbryanlarsen16d ago0 comments

A quick Google shows EREOI of solar panels at 10-30 depending on study.

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The PV manufacturers themselves say its 4. Those studies you mention say you could make them at 10-30 in theory if you could somehow purify the poli-silica differently. If we made PVs in the west with natural gas (and carbon recapture), perhaps it could get to that number (but perhaps not). However, PVs aren't made in the west and the poli-silica isn't purified with gas but instead using coal. That's why those numbers are different. And for reference, we could have made those PVs in the west, however politicians chose not to.

ben_w16d ago

> The PV manufacturers themselves say its 4.

You've not cited anything for this so far as I can see, but this claim is obviously false.

Reason being, the entire system in my driveway will have paid for itself in one year, including delivery cost and inverter and the aluminium stand it's mounted on (the small bit of aluminium in the stand is the most energy intensive part of the whole kit), and the weakest part of that system still has a lifespan of 25-40 years, and even that as a % reduction in output from peak not as a hard cut-off.

Even if 100% of the cost was energy, even with the 5x price differential between where I am (Domestic Germany) and where they were made (Industrial China, where the low energy cost is… ah… due to renewables, because coal's really expensive :P), it's obviously not an ERoEI of 4 even on the low end of that lifespan.

Given all that and doing the maths, what I will need to replace and when (or rather, kids whose mother I have yet to meet will need to replace when I'm in a retirement home), the ERoEI is at a minimum 14 even if 100% of the cost of replacement panels is energy.

The cost is almost certainly less than 100% energy. Every step of the industrial process wants its own profit margin.

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