Comment by biren34 | Hacker News Reader

Comment by biren34 | Hacker News Reader

I have real problem with this discussion of "cheap" when it comes to wind and solar.

1. The marginal cost per kWh is calculated based on amortizing upfront costs over 20+ years, and those schedules have often proven to be quite optimistic.

2. The marginal cost per kWh is only a small piece of the puzzle when it comes to intermittent power sources.

The proper cost needs to attribute the cost of matching supply and demand. The supposedly easy answer is storage, but storing electricity is hard. Grid scale batteries are quite expensive and general deployment would cause a very real spike in the cost the raw materials. With proper accounting, the cost of renewables are not cheap at all, as proven by Germany and California.

3. The renewables industry likes to downplay the sheer volume of fossil fuels required to manufacture the parts. The energy ROI on this is quite poor, and in many cases, we would have been better off skipping the intermediate step and burning the oil and gas directly.

>3. The renewables industry likes to downplay the sheer volume of fossil fuels required to manufacture the parts. The energy ROI on this is quite poor, and in many cases, we would have been better off skipping the intermediate step and burning the oil and gas directly.

I'm assuming you're referring to Ferroni and Hopkirk (2016) which claimed ERORI of ~0.8-1.7.

You should be aware that their work has been pretty thoroughly picked apart - the rebuttal produced immediately after the above, by 27 international scholars, suggests a ERORI of 7-8. It has likely improved since that time.

https://www.sciencedirect.com/science/article/pii/S030142151...

I'll have to take a look. Thanks!

> The renewables industry likes to downplay the sheer volume of fossil fuels required to manufacture the parts. The energy ROI on this is quite poor, and in many cases, we would have been better off skipping the intermediate step and burning the oil and gas directly.

Is this from electricity (which could be renewable in future), or is there an actual hard requirement for carbon in terms of burning very hot materials to generate heat in the manufacturing process or something?

Some of it is in base materials and some of it in smelting requirements (though I'm not 100% sure how much of that could be replaced by electricity).

Most of it is in the mining, refining, and transport of the massive quantities of metals needed to manufacture and install the combination of generation, transport, transformation, and storage equipment + the second/third order equipment to manufacture the electrical equipment.

Our supply chains are dependent on fossil fuels for all of this, and we're a long long way off from replicating even a fraction of it with a purely electrical version.

If we do choose to pursue that goal (which I think is worthwhile), the renewables still lack the energy ROI to make it feasible. We can do it, but it pretty much requires wide scale adoption of nuclear for the thermodynamics to work out.

You know there is a fatal flaw in your third argument. Maximum resource cost is bounded by the cost of the renewables. Yet their cost is going down despite producing the same or even more energy. This is completely incompatible with your premise of ERORI always staying below 1.

If burning oil and gas directly was more efficient then it would be impossible for costs to go down beyond a certain point and subsidies would have to grow over time as more and more renewables are deployed.

The reality is that the opposite happened. Countries jumped onto renewables as they became cheaper [0] and subsidies are shrinking across the board.

So whatever your source is, it either had an agenda or it is simply incompetent.

[0] please don't tell me that they didn't become cheaper when the submission article is entirely about renewables becoming cheaper

You're ignoring the differing resource costs. China can freely consume domestic, brown coal for manufacturing purposes, in a significantly cheaper way than any Western country.

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