this post was submitted on 13 Sep 2024

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It's a pretty solarpunk fact that small, distributed wind turbines use steel more efficiently than big centralised ones (solar.lowtechmagazine.com)

submitted 1 month ago by [email protected] to c/[email protected]

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The most steel-intensive power source – by far – is the modern wind turbine. The steel intensity of a wind turbine depends on its size. A single, large wind turbine requires significantly more steel per megawatt of installed power than two smaller wind turbines.

The link is from the-most-solarpunk-website and is mostly about steel in general, but I wanted to pull out that one fact.

Wind and solar energy are not "good for the environment"; they pollute; it's just that we hope they pollute less than the alternative. One major reason they pollute is because they require a lot of steel to build. But the household-scale or village-scale ones use less

de Decker is citing: Topham, Eva, et al. “Recycling offshore wind farms at decommissioning stage.” Energy policy 129 (2019): 698-709.

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[–] [email protected] 20 points 1 month ago (1 children)

They use steel more effectively, but use other resources like wind, land, labor, and electronics less effectively, and all of which are harder to recycle. It also didn’t mention household or village scale as much as was still comparing very large grid scale systems, which is important as once you get much smaller than that energy efficiency falls off a cliff.

Finally, while a detailed look into a specific resource can be very interesting, it’s important to take a holistic look at how energy sources compare and not just evaluate on one figure.

Ultimately, as our ability to manufacture steel is not currently a major constraint to decarbonization, more important limitations like installation and maintenance costs are going to be dominant at least for the next few decades. Similarly as the low hanging fruit like electricity generation make up less and less of our collective GHG emissions, we’ll have more resources like plentiful wind energy to throw at problems like decarbonizing steel, as its still a problem will have to solve sooner or later.

[–] [email protected] -3 points 1 month ago* (last edited 1 month ago) (3 children)

They use steel more effectively, but use other resources like wind, land, labor, and electronics less effectively, and all of which are harder to recycle

Wind is a renewable resource. Saying wind is not easy to recycle is incoherent.

Electronics is the only one of the four you mentioned where recycling is a relevant concept.

As for wind farms being an effective use of land, that's just obviously wrong. You can't even have livestock near them.

As for less labour-efficient, I'd've thought that's part of solarpunk: being less capital-intensive/more labour-intensive.

[–] [email protected] 9 points 1 month ago

Sonori is completely right here, and it feels in bad faith to critique the semantics of their comment rather than the substance of them.

One of the things that is difficult about solarpunk is that there is a huge divide between where we currently are and where we want/need to be. Smaller turbines for a more distributed power grid is a part of a great future to look towards! But it's not the reality of our power demands now, which necessitate larger turbines and more steel production to meet any of our climate goals. Speaking coherently through that divide can really lead to mismatched expectations and miscommunications.

[–] [email protected] 6 points 1 month ago* (last edited 1 month ago) (1 children)

Precisely, good stable wind blowing when we need power is not something we have an unlimited amount of, like times we can recycle steel. The steel in todays wind turbine is the steel in a thousand years from now’s turbine, where as the co2 that got pumped into the atmosphere because that turbine wasn’t enough is also the co2 killing people in a thousand years. The higher you get a turbine above the ground, the less turbulence it will see, and the more constantly it will be in the right range to generate power.

The more you can count on it, the less battery and hydro you need to cover when the winds not blowing, and thusly the less space and turbines you need.

As for labor efficiency, i’ve always though of the goal of solarpunk to be a world where we’ve settled out into a way of life that can be maintained long term and where people are free to do what they want and help out where they can instead of worrying about if they’ll earn enough from the megacorp to have heat and food next month.

While you still need someone to do dangerous and unpleasant things like climbing turbines, ideally you’re only asking as few people as possible to do so as you need.

And given that even in that future people will still be paying the price in lives for the GHGs we emit today, we owe it to them and possibly us if we live long enough to shrink the river of co2 we’re putting out as fast as we can, as every fossil plant that is replaced by clean energy today is decades of that’s plants cost gone.

[–] [email protected] 1 points 1 month ago (1 children)

The steel in todays wind turbine is the steel in a thousand years from now’s turbine, where as the co2 that got pumped into the atmosphere because that turbine wasn’t enough is also the co2 killing people in a thousand years

FYI making steel emits carbon: kinda the main point of the article.

[–] [email protected] 3 points 1 month ago

No shit, in a fossilized economy everything emits carbon, and low co2 new steel production is still in its infancy. Nevertheless it emits far, far less carbon than running a natural gas plant for the same power, and as the article points out, can and is continually reused forever with no new carbon emissions beyond that of the enegy used to transport the material and power the arc furnace.

The startup cost in carbon just means there is a delay in between when a turbine is built, and when it is produceing zero carbon energy. Studies show that even the most steel intensive offshore turbines repay this debt in under a year, and again, this is why we need to be getting as much wind energy online as soon as possible.

If going to a smaller turbine design means that you save four months worth of startup carbon, but means a wind farm only captures two thirds as much wind energy over its three hundred month design lifespan then going with the smaller design will have effectively cost nearly a hundred months worth of output to save four. While that two thirds number is going to very by project constraints, the reduction doesn’t need to be very large to work out to a net carbon savings, even if you couldn’t recycle steel at all.

As things like available project land, projected ongoing maintenance budget, and most often capital availabllity ultimately constrain a given projects size and net generating capacity, it makes sense to go for the larger turbines that more efficiently make use of these limited resources, instead of the practically unlimited in this context supply of steel.

In short, optimizing for steel use is effectively producing kilotons of ongoing co2 emissions to save tons of co2 once.

[–] [email protected] 1 points 1 month ago

Livestock aren't an efficient use of land in the first place, and you can absolutely graze around turbines, at least according to this: https://www.windenergy.org.nz/resources/for-developers-and-landowners/how-to-host-a-windfarm

It appears there are even advantages to crop farming under turbines: https://agupdate.com/agriview/news/crop/wind-farms-impact-crops/article_bb057e6c-e58b-5990-b4d5-62640803121f.html

Obviously can't do any aerial crop dusting around turbines.

[–] [email protected] 9 points 1 month ago (2 children)

Steel can be pretty easily recycled, so it's not too bad all in all.

An addition benefit of using smaller but wider scale turbines is the reduced need for electrical transmission lines. A large chunk of our problems is the transmission lines needing updated/expanded on to handle more electrification.

[–] [email protected] 6 points 1 month ago (2 children)

The larger the wind turbine the better an investment it is.

For better or worse our green transition is primarily capitalist. That matters a lot here.

Wind speeds are significantly higher every meter you get above the ground. The larger the blade the better it performs. Windmills can't cluster together too closely since they induce turbulence...

It all means that bigger is better here.

[–] [email protected] 6 points 1 month ago

It all means that bigger is better here.

I don't disagree with anything you said. I was only pointing out an additional benefit outside of the one the post mentions.

[–] [email protected] -2 points 1 month ago

The larger the wind turbine the better an investment it is.

For better or worse our green transition is primarily capitalist. That matters a lot here.

Wind speeds are significantly higher every meter you get above the ground. The larger the blade the better it performs. Windmills can’t cluster together too closely since they induce turbulence…

It all means that bigger is better here.

I don't see anything punk about this at all, sorry. Reads anti-punk beginning to end.

[–] [email protected] 1 points 1 month ago

Steel can be pretty easily recycled, so it’s not too bad all in all.

All in all, it is roughly 9% of greenhouse gas emissions

[–] [email protected] 7 points 1 month ago (1 children)

That‘s interesting. My understanding was that wind speed/force rises exponentially with heigth and so a 150 high turbine is much more powerful than a 50 m high turbine - and not only 3 times as powerful, as one expects.

[–] [email protected] 2 points 1 month ago

The exponential relationship is between speed and energy, rather than height and speed.

[–] [email protected] 1 points 1 month ago

wind and solar are essentially energy multipliers. I do not know of any wind solar being completely manufactured using wind and solar.