Running the numbers

170 t coking coal

At 27,000 MJ/t for coking coal, thats 4590,000 MJ per windmill.

Running at 2MW, or 2 MJ/s the windmill needs to run for 2,295,000 seconds to cover its energy. That is equivalent to 26.5 days.

At 20% utilisation, the windmill will have recovered its energy in 132 days.

Dont trust, verify

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Discussion

you forgot the 260 tons of steel and the 300 tons of iron

also the cost of demolition which is excessive, lot of highly toxic waste

and the disastrous effect on the environment: hundreds of birds killed each

Iron is the ore used to make steel, it is not two ingredients, but two steps. The energy for this conversion comes from 170 t of coking coal.

At 11.5MJ/t to mine the iron ore, it takes 3450 MJ to mine the ore. Thats 0.5 hours of windmil generation.

Coal is probably similar.

The coking coal is produced from metallurgical coal. 1.5 to make 1 t of coke. Some energy is lost in the conversion. That would make the windmill an extra 33% more time to recover.

The issue of matching demand is more significant. The wind doesn't always blow when you need to power, but in terms of return on energy invested it's a pretty short payback