Wind turbines

[oil pan 4]

So what’s the carbon foot print of a wind turbine with 45 tons of rebar & 625 yards of concrete?
Its carbon footprint is massive – try 241.85 tons of CO2.
Here’s the breakdown of the CO2 numbers.
To create a 1,000 Kg of pig iron, you start with 1,800 Kg of iron ore, 900 Kg of coking coal 450 Kg of limestone. The blast furnace consumes 4,500 Kg of air. The temperature at the core of the blast furnace reaches nearly 1,600 degrees C (about 3,000 degrees F).
The pig iron is then transferred to the basic oxygen furnace to make steel.
1,350 Kg of CO2 is emitted per 1,000 Kg pig iron produced.
A further 1,460 Kg CO2 is emitted per 1,000 Kg of Steel produced so all up 2,810 Kg CO2 is emitted.
45 tons of rebar (steel) are required so that equals 126.45 tons of CO2 are emitted.
To create a 1,000 Kg of Portland cement, calcium carbonate (60%), silicon (20%), aluminium (10%), iron (10%) and very small amounts of other ingredients are heated in a large kiln to over 1,500 degrees C to convert the raw materials into clinker. The clinker is then interground with other ingredients to produce the final cement product. When cement is mixed with water, sand and gravel forms the rock-like mass know as concrete.
An average of 927 Kg of CO2 is emitted per 1,000 Kg of Portland cement. On average, concrete has 10% cement, with the balance being gravel (41%), sand (25%), water (18%) and air (6%). One cubic metre of concrete weighs approx. 2,400 Kg so approx. 240 Kg of CO2 is emitted for every cubic metre.
481m3 of concrete are required so that equals 115.4 tons of CO2 are emitted.
Extra stats about wind turbines you may not know about:
All this stands on a concrete base constructed from 45,000 Kg of reinforcing rebar which also contains over 481 cubic metres of concrete (that’s over 481,000 litres of concrete – about 20% of the volume of an Olympic swimming pool).
Each turbine blade is made of glass fibre reinforced plastics, (GRP), i.e. glass fibre reinforced polyester or epoxy and on average each turbine blade weighs around 7,000 Kg each.
Each turbine has three blades so there’s 21,000 Kgs of GRP and each blade can be as long as 50 metres.
Each and every wind turbine has a magnet made of a metal called neodymium. There are 2,500 Kg of it in each turbine.
The mining and refining of neodymium is so dirty and toxic, involving repeated boiling in acid, with radioactive thorium as a byproduct.
China is saving all their byproduct thorium. This is why they are developing thorium nuclear reactors.

That doesn't include mining for the steel and concrete raw and finished product transportation, all the electrical infrastructure needed to connect them to the grid.

I like wind power.
Just don't give it a free pass and pretend like it never produced any pollution.
Not so great.

[Frank Lee]

I still say conservation is best but Duhmerica ain't having it.

[Ecky]

Other types of power plants also use concrete and steel. Maybe the ratio of concrete and steel to power production is a little better for coal or nuclear or hydro.

[Frank Lee]

The Hoover dam weighs 6,600,000 tons. It took 3,250,000 cubic yards of concrete to build the dam itself.

.

[RedDevil]

Nobody believes the production of windmills goes without pollution.
Nor does the production of any other power generating device.

As for the steel, just today Tata Steel announced its HIsarna ironmaking plant has successfully reduced CO2 production by 50%.
The HIsarna process combines two stages in the reduction process in one and can run continuously.
Cheaper and cleaner steel. That may lead to a shift toward full iron and away from concrete construction.
It won't solve all the worlds problems at once, but it is a step in the right direction. It would shave several tons of CO2 off your equation.

[roosterk0031]

The concrete is in the foundation of the towers. They made a partial concrete tower here in Iowa a few years ago. Video of the construction.

https://www.youtube.com/watch?v=qXN1UAv1anQ

One of my cousins used to service them, till a co-worker fell to his death.

[NeilBlanchard]

There is even more concrete and steel, and copper, and electronics, and water - used in nuclear power plants. It takes a lot of energy to mine and refine, and enrich, and transport nuclear fuel.

It takes 10-20 YEARS to build a nuclear power plant. The spent nuclear fuel has to sit in pools of water for a decade or more - and the water has to be pumped, and then processed afterward; because it is contaminated and radioactive.

A lot of energy is used to decommission a nuclear power plant - and it will probably take another 10-20 years to do this. It will take a lot of energy and steel and concrete to build the dry casks - which last only 100 years. Rinse and repeat, for a very long time.

++++++++++++++++

Wind power uses no fuel. So, it has a much lower energy overhead, and the foundations can be reused.

[RustyLugNut]

Originally Posted by NeilBlanchard

There is even more concrete and steel, and copper, and electronics, and water - used in nuclear power plants. It takes a lot of energy to mine and refine, and enrich, and transport nuclear fuel.

It takes 10-20 YEARS to build a nuclear power plant. The spent nuclear fuel has to sit in pools of water for a decade or more - and the water has to be pumped, and then processed afterward; because it is contaminated and radioactive.

A lot of energy is used to decommission a nuclear power plant - and it will probably take another 10-20 years to do this. It will take a lot of energy and steel and concrete to build the dry casks - which last only 100 years. Rinse and repeat, for a very long time.

++++++++++++++++

Wind power uses no fuel. So, it has a much lower energy overhead, and the foundations can be reused.

You are absolutely correct about the nuclear power plant costs. But those plants should run for 40+ years and produce Giga Watts of power near constantly. Wind turbines will not last 40 years and will need replacement well before that. Also, due to the dispersed nature of wind energy, you will need a large number of them dwarfing the mass of the nuclear power plant.

As I've pointed out in other posts, the sheer volume of renewables results in titanic bulk. Though low grade in pollution, the sheer mass of it all results in tremendous pollution that is distributed around the environment instead of concentrated.

And if people weren't so frightened of nuclear power, generating plants could be built in 7 year time-frames using modern designs and techniques. The same can be said for waste disposal as modern designs produce a small fraction of current designs. Modular molten salt reactors will be smaller and fast neutron reactors will be more thermally efficient. The fact that current plants will need waste stored on site is a good thing because, as Oil Pan4 pointed out, much of the old fuel waste can be burned in new Generation 4 reactors. Siting new reactors on old power generating facilities leverages the existing distribution network. That was the plan all along. Upgrades of nuclear cores doesn't have to be as upsetting as they are now. NIMBYs are killing any possibility of this happening economically.

[NeilBlanchard]

What pollution results from renewable energy?

Distributed energy generation is a BIG advantage.

[redpoint5]

Well, the whole first post in this thread discusses the pollution and impact of building a single wind turbine.