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Comment by yeureka | Hacker News Reader

I recently read, and recommend a book titled "Here Comes the Sun" by Bill McKibben. There's a passage where a calculation is made of the amount of minerals that have to be mined in order to build renewable energy to cover all current energy needs. This quantity is huge. However it is equivalent in mass to the amount of fossil fuels that are extracted every year. The major difference is that the equipment for renewable energy will last decades whereas the fossil fuels are burned and need to be dug up constantly, for ever.

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Solar panels etc. will last decades and can and will be recycled afterwards. Further, most materials needed for renewable energy infrastructure (iron, lithium) are highly abundant on earth. Most of the suppliers work to use cheaper (=more abundant) materials in their products, replacing lithium with sodium in batteries and silver with copper in solar panels. Wind turbine blades are produced now using re-solvable resins.

Not only are older solar panels recyclable, but efficiency gains in panel construction mean that multiple newer panels can be created with the resources from older panels.

And iron (steel) is the most recyclable material we have.

Wind turbines are not recyclable[1]. Besides, the foundations use a massive amount of concrete (nowadays often extracted from the seabed, with all the problematic ecological consequences involved), that stays forever in the ground.

[1] https://www.sciencedirect.com/science/article/abs/pii/S23527...

Existing wind turbines turbines are not recyclable - new wind turbines are.

Except, that's not even true. Some existing wind turbines are not recyclable.

Except that's not entirely true either! The tower portion of the turbine is usually steel, and easily recyclable! The nacelle, too. It's the base and the blades that can't be recycled.

Except that's not entirely true either! Existing turbine blades are made (mostly) of fibreglass, which is made of the fibre and the resin. The fibres aren't reliably as strong when recycled (which makes them not-very-useful when recycled), but the resin is just fine. And of course, if the blade is e.g. carbon fibre, then you can either re-use it or just burn it.

So, you statement should be that some (components of) existing wind turbines cannot be profitably recycled with current technology.

The wind turbine's concrete base doesn't need to be smashed up or ignored, incidentally - it can be re-used. Concrete is much sturdier than the e.g. gearbox.

None of this is economically profitable, which is why right now it ends up in massive landfils. The concrete base is reinforced with steel beams and weights so much that you can't move it.

Also sorry but I would require a citation for "new wind turbines are recyclable". That the tech exists doesn't mean that all installed turbines have it.

The linked article is misrepresented.

Two points regarding blade recycling techniques taken straight from the top of the article:

- Cement co-processing and chemical dissolution are primary viable methods, yielding $27.57/ton and $199.71/ton returns respectively.

- Chemical recycling achieves top circularity (PCI=0.7) and notable carbon reduction (−0.475 t CO₂/ton).

Chemical recycling is not yet ready for industrial use; cement co-processing is.

Concrete recycling is actually a pretty big deal. For most of building history here the standard material to put behind basement walls, retaining walls, and so on, for drainage was crushed scoria. Now it's crushed concrete. Some amount of effort but you're recycling existing stuff, and they recover the reinforcing steel as well.

Cement co-processing is not exactly recycling as the original material (fiberglass) can't be reused for its initial purpose.

Who cares? Those blades and that concrete are totally inert and just sit in the ground after their useful life. The ground already has lots of rocks in it.

It defeats the "renewable" designation, since it is quickly consumed and thrown away. Compare this with hydropower, where a dam can last centuries.

But if you repower the wind mill, the foundation can serve for the next turbine

Curious you're so worried about "ecological consequences" but only when it's window power.

The problem is that those power sources are marketed as "renewable" (they aren't as they quickly end in landfills), are intermittent, require fossil fuels for when the wind doesn't blow, and are not profitable.

One could also say that they change heavily natural landscapes, but this is a matter of taste.

> they aren't as they quickly end in landfills

Do you also lead a zero-plastic, zero-waste lifestyle?

> are intermittent, require fossil fuels for when the wind doesn't blow

Batteries.

> are not profitable.

Let the businesses worry about that.

One point that gets very little coverage is that fossil fuels are a limited resource. Once they used they are gone.

The materials for renewable energy are still in a usable form.

The finiteness of fossil fuels isn't real in a practical sense.

The globe burnt about 8.8 billion tons of coal in 2024. Which is a huge amount. This is the peak, most estimates are that we will reduce from there.

Australia alone estimates that it has 147 billion tons of economically recoverable coal. That is Australia alone could supply the entire globe at peak usage for over 16 years. And Australia only has about 14% of the globes coal reserves, we can keep burning coal at this pace for at least the next hundred years. And it a hundred years the scope of what we consider to be economically recoverable will have expanded greatly, further increasing our supply.

We will cook ourselves before we run out of fuel.

A more sci-fi apocalyptic angle on this fact is the argument that fossil fuels, especially easily accessible ones, are necessary to bootstrap a futuristic multi-planetary civilization. They provide the easy energy necessary to support an industrial revolution and the society and technology level necessary for more advanced and renewable forms of energy necessary to really build and sustain an advanced civilization long term.

But because they take so long to form, stumbles along the path of energy advancement mean a planetary civilization could run out of fossil fuels before reaching the level of advancement necessary to move beyond them. At that point, the civilization is essentially doomed since they lack the technological ability to move beyond fossil fuels and they lack the energy resources necessary to develop that technology.

CO2 can be converted to methane. It just isn't profitable to do so yet. After the fossil fuels are depleted, it will be a viable niche for storable energy where renewables aren't practical.

Once fossil fuels run out, most exclusively-fossil-fuel-based activities will simply cease to be economically feasible.

That doesn't contradict your statement, of course. But in the long term the fossil fuel niches will start looking more like today's rocket-fuel niches.

Why is this conversion desirable?

Methane synthesized from excess renewable power can store that renewable power for years, handily fixing the whole "Sun don't shine every day" problem.

It's durable energy storage and can be easily moved around like liquid fuels.

It also would remove CO2 emissions from things like airplanes, which won't be able to be battery powered in the near future, and could renewably replace chemical feedstocks in lots of industrial processes.

But this requires immense industrial capability, probably some serious innovation in absorbing CO2 from the atmosphere because that's basically an unsolved problem right now, and a massive oversupply of solar power which cannot happen under market systems because nobody builds infrastructure to sell power at below market rates.

It might be a 50 year plan.

You swap a plentiful greenhouse gas for another greenhouse gas that is burnable at no net environmental cost.

I don't think you realize how much OIL we still have. The warnings about running out of oil is long long gone.

You're right, it's not infinite, but we are in no crisis now or in the foreseeable future.

"You're right, it's not infinite, but we are in no crisis now or in the foreseeable future."

Have you not heard of climate change influenced by fossil fuel burning, or are you a climate change skeptic?

The general consensus is that climate change is a crisis, now and in the foreseeable future.

Yes of course, but i have not heard of a reasonable action plan given the world's population and basic human nature.

> One point that gets very little coverage is that fossil fuels are a limited resource

Every time someone uses the term “renewable” they are providing coverage to this notion.

It is deeply bizarre you can think otherwise.

The renewable in renewable energy sources is referred to, indeed, the energy sources.

The user was arguing that the materials to exploit them are renewable too.

But it creates enough cash to redirect all ire away to weakly lobbying industries, like aggrarian-sector or other weakly lobbied sectors like nuclear.

Only there is no forever when you're talking about a finite resource, like fossil fuels.

They're talking about our nascent circular economy.

Recycling now recovers >95% of raw minerals (and will continue to improve).

The learning curves for battery and solar tech will more than make up the for the shortfall.

Meaning at some point in the near future (2050 IIRC), humanity will have mined all the lithium it'll ever need.

Also, in the same time frame, it'll be economical to mine our garbage dumps. Further reducing the need to extract raw materials.

"Recycling now recovers >95% of raw minerals"

Not of plastic - recycling rates are decreasing. This is largely due to the excess ethane begin produced as a by-product of US fracking.

The ethane is converted to ethylene, then to polyethylene as a cost below that of collecting, cleaning, and processing used plastic.

True. The situation for both off-gassing and plastic recycling is rather bleak.

Sorry for being vague; I was only referring to economically valuable minerals used in electric batteries.

Aqua Metals has previously said they'll be able to reuse battery quality graphite (from batteries) as well (vs releasing it as CO2). But my recent scan of their progress wasn't very encouraging.

Learning more about Redwood Recycling stack is on my to do list.

Source? These are big claims and the collective shouldn’t rely on your recall as fact.

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