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Comment by ph0rque | Hacker News Reader

"Looking at the bulk of the research, it’s more likely that solar panels, over their lifetime, generate 10-15 times as much energy as it takes to produce them and their associated hardware. That number may be as high as 25. And it’s rising over time." http://rameznaam.com/2015/06/04/whats-the-eroi-of-solar/

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There's also the fundamental mistake that not all energy is equal.

Energy in the form of electricity is far more useful than energy in other forms as it can be used directly. With other forms it will generally need to be converted first, with massive efficiency losses which are ignored by EROEI proponents.

So for example while oil might be said to have an EROEI of 14.5, it loses 80% of that when used for the common purpose of turning a cars wheels, giving only a 2.9. generally those who quote EROEI numbers would claim this makes industrial society a literal impossibility.

All analysis I've seen indicates pretty much the opposite. Electricity is way less useful than diesel fuel. Our civilization critically runs on diesel and no one has figured out an even theoretically viable way to substitute in batteries where diesel is used in logistics, resource extraction, and pumping.

These claims are based on simplistic spread sheet models. We have REAL WORLD DATA. The real world experience throughout europe and the USA shows net losses. I repeat: if it worked the plants would be profitable and they would be going up without tax subsidies. Do you dispute this? Does the legal environment somehow prevent entrepreneurs throughout the western world from selling solar power into the grid?

Nothing prevents anybody from selling solar power. Lots of solar farms are live and many more are being built.

https://en.wikipedia.org/wiki/List_of_photovoltaic_power_sta...

(note how the biggest ones are all new)

If you think tax subsidies have anything to do with EROI (i.e. EROEI) you are very confused. This is calculated on the basis of Wh/Wh. Simple dimensional analysis shows that $ doesn't show up at all in the calculation.

Of course tax subsidies are useful to bootstrap on a $ cost basis, but with current costs and rate of falling costs even that will soon become unnecessary (let's get rid of fossil fuel subsidies to make this "real world data" comparison fair though).

Cash flows are in fact a reasonable proxy for energy in many cases. Manually tallying up the uses of energy and materials is a handwaving exercise at best, but net losses of cash in the energy industry indicate with certainty that you not yielding net energy to society as an enterprise.

> they would be going up without tax subsidies.

They don't even build Walmarts without tax subsidies these days.

Can you review this [1] and ELI5 why solar seems to work in China, but the Sun doesn't shine enough to make the economics work in the west according to your research?

[1] https://en.wikipedia.org/wiki/Solar_power_in_China

> I repeat: if it worked the plants would be profitable and they would be going up without tax subsidies

Right, so on that basis these bids below the grid rate indicate that they now work?

Bids are speculations.

Bidders are very frequently unable to actually deliver. See pretty much any highway project ever.

Agreed on that.

Can you link real world data?

Are externalities (CO2 output) taken into considerations in your unsourced REAL WORLD DATA!!~!

I would have bought a house without a tax subsidy.

But there is one, so I'm sure as hell taking it.

> if it worked the plants would be profitable and they would be going up without tax subsidies.

No, it's the other way around: fossil fuels are subsidized by governments to the tune of $4.8 trillion a year, so solar needs to be subsidized as well to be able to compete.

http://www.imf.org/external/pubs/cat/longres.aspx?sk=42940.0

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