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Wind turbines are dirty sources of energy.

They do not supply consistent baseload energy.

Turbines are just giant machines built off the backbone of oil and natural gas.

Humanity doesn't make turbines with renewable energy.

Trucks move steel. Earth movers navigate. Cranes push up structures.

All of this requires diesel fuel.

These figures aren't accurate, but precise enough.

Diesel ships transport critical turbine cement, steel, and plastics.

A 5 Megawatt turbine requires 900 metric tons of steel.

150 Tons - concrete foundations 250 Tons - rotor hubs and nacelles 500 Tons - towers

Let's play with some scenarios w/ conservative back of the napkin calculations:

If wind was 25% of global demand by 2030 *(w/ capacity factor of ~40%)

2.5 Terawatt hours of wind turbines require 500M tonnes of steel. (w/o towers, wires, transformers. etc…)

30-40 gigajoules/ton are required for Turbine steel.

500M tonnes of coal to make this much steel.

60 meter foils. (theat each weigh ~20 tons) make up the 4 MW turbines.

Glass fiber reinforced resins are made of hydrocarbons.

Glass is made with natural gas furances.

The rotor’s mass of such a turbine is ~20 metric tonnes. (About 75 million metric tonnes of oil)

Coal makes iron.

Coal + petro make kilns.

Naphtha and Liquefied natural gas make synthetic plastics for fiberglass.

Diesel makes ship fuel.

PS: In 2016, the global volumetric production of steel was ~1500 Million tonnes. (+/- 10%)

The wind turbine hydrocarbon based lubricants industry is fast growing ---- https://www.globenewswire.com/news-release/2019/02/20/173857...

This is often repeated, and is incorrect. life cycle analysis of wind turbines suggests that the carbon and energy pay off is anywhere from 1/2 to 2 years, after which point, the turbine is a net win compared to fossil fuels sources. In this context, life cycle analysis includes all of the embedded energy used to manufacture and operate the wind turbine. See, for example, https://www.ourenergypolicy.org/wp-content/uploads/2014/06/t...

There is absolutely nothing wrong with putting up a renewable energy source using hydrocarbons if alternative sources of materials and transportation are not available.

If it were up to you then we'd all wait until renewable energy would be able to produce all of those goodies and move them around but then it would never happen in the first place.

This is called a transition. You could make the same arguments for electric vehicles and they'd be just as broken.

For those interested in actual analyses of the lifecycle emissions from various energy generation types, NREL has a fantastic review of the literature here:


Needless to say, it's a bit more precise.

While you’re numbers are wildly off base, that post represents a critical misunderstanding of what’s involved.

Using hydrocarbons to make stuff has zero direct impact on climate. CO2 requires carbon to end up in the air not turbines.

PS: Global annual electricity demand is ~21,000TWh. 25% of that is 5,250 TWh. A 5 MW turbine at 40% average output produces 5 * 0.4 * 24 * 365 = 17,520 MWh so you want 300,000 of them.

Using hydrocarbons to make stuff has zero direct impact on climate. CO2 requires carbon to end up in the air not turbines.

Where do you think CO2 ends up when you use hydrocarbon to make steel or aluminum?

I was referring to his comment ‘The wind turbine hydrocarbon based lubricants industry is fast growing.’ Talking about this as if it was a significant issue is completely failing to understand what’s involved.

Anyway, it depends on what you’re doing, if your for example using coal to add carbon to iron to make steal the it ends up in the steel. If you’re burning it to make heat then it ends up in the air.

The average CO2 intensity for the steel industry is 1.9 tons of CO2 per ton of steel produced. Taking into consideration the global steel production of more than 1,3 billion tons, the steel industry produces over two billion tons of CO2.

That’s ~5% of global emissions per year, though looking at a number per decade and comparing it to a number per year is rather big difference.

I think with steel you can guesstimate about 4-5kwh per kg. The energy has to come from somewhere. Right now it comes from coal and nat gas.

Reducing the carbon intensity of steel and also concrete production are things that being worked on. Companies in those industries aren't willing to be martyrs but unlike fossil fuel companies they aren't hostile either.

I'm suspicious of some of your numbers. For example, what does this line mean: "The rotor’s mass of such a turbine is ~20 metric tonnes. (About 75 million metric tonnes of oil)"

Where does the oil come in, and why is the ratio 3.25 million to one?

Sure, wind turbines are large structures that take energy to build. But they are mostly made from steel, one of the most recycled materials. Glass is equally well recyclable. And you make wind turbines once and they need little resources for the rest of their lifespan. Currently their lifespan is 20-25 years, but as the technology matures and new turbines stop being massive improvements over older designs that lifespan will go up. For comparison a coal plant lasts about 40-50 years, and is also a massive heap of steel and concrete.

500M tonnes of steel over 10 years is ~3% of the worldwide steel production, for some context.

It would be more helpful to know how much carbon an average turbine "costs" and how long an average turbine lasts and how much electricity it produces.

I think most people are aware it costs a lot of carbon to make anything, windmills being no exception.

You sound like you might know some of the specifics, so I'm hoping you could inform us further.

If you take that view point what renewable resource doesn't require some product built for it's harvest?

I was told similar things by wind farm engineers.

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