Wind Power: Power generation with invisible costs

From a powerpoint I made in 2021 and gave to the IPA Institute of Public Affairs

How Wind Power works
Historically, wind power is older than writing or culture. It was used to power ships from ancient times, or mills for grinding food. Hammurabi’s Codex circa 1750 BC refers to mills doing mechanical work. Netherlands is famous for her Windmills which drained lowlands of water. Nowadays wind turbines may be off shore (very big) or, on shore.
What wind power generates (profit)
A wind turbine has a rating, but that is a maximum output for its’ power, which practically will not be achieved
A turbine cannot safely produce energy in wind speeds below 25 kph and above 88 kph
The local weather gives a rating (%) for effective use of a turbine, typically between 30 and 50% of output
Eg a 1.5 MW operating at 25% efficiency can produce 1500 x 0.25 x 365 x 24 = 3, 285, 000 kWH a year. This assumes 24 hour a day availability which does not happen.
2 million kWH in Victoria averages $560,000 at $0.28 per kWH per year
A lifetime (20 year) return would be $11 million, before costs

Costs of wind power
Wind power costs include production, maintenance and lifetime replacement.
To produce a turbine, materials needed are 8700 kg steel and zinc alloy tower. $US75/ton for elec, coal,
A fiberglass nacelle of 10k kg including gearbox and drive
A 15 m long blade contains over 1100 kg of fiber glass and specially sourced wood
Maintenance of a generator averages $Aud62k a year. This figure is from US and includes insurance, land rent, service, repair, spare parts, admin and power
Wind turbines need to be junked, as they can’t be recycled. $AUD750k based on US costs. A UK off shore windfarm cost 100 million pounds to decommission on average 323 windmills on average. (11000 over 34 farms) or 300k pounds per windmill. The net loss is over a billion pounds over the lifetime of all 11k windmills.

Net returns?
11k windmills in UK have a net return of minus a billion pounds in 2021. That is 100,000 pounds per windmill on average. After they generate power for the grid, they end up costing the taxpayer 5000 pounds each year if they function properly, but much more if they don’t.

Bibliography
https://sciencing.com/wind-turbine-size-vs-power-23676.html
https://www.finder.com.au/average-cost-of-electricity
http://www.madehow.com/Volume-1/Wind-Turbine.html
https://weatherguardwind.com/how-much-does-wind-turbine-cost-worth-it/
https://www.instituteforenergyresearch.org/renewable/wind/the-cost-ofdecommissioning-wind-turbines-is-huge/
http://large.stanford.edu/courses/2016/ph240/martelaro1/
https://www.netzerowatch.com/the-cost-of-wind-power-worse-than-wethought/
https://www.netzerowatch.com/all-news/worlds-largest-offshore-wind-farm-unprofitable-government-funded-report-confirms