I know an engineer that designs the blades and has worked on maintenance in the past too. They actually do use a mechanical system to regulate the speed on most modern windmills. There are brakes as well as mechanisms to adjust the pitch of the blades to gather more/less wind. If you see a bunch of windmills, watch, they are always the same speed.
The blades are mostly fiberglass and balsa wood. I'm not sure that many useful materials could be taken out of them. The posts are steel, but if I had to guess from my own industry they get abandoned in place when they are end of life. It likely costs more to decommission them than the materials are worth, and spending expense $ on such projects looks bad to pretty much any financial report for a public traded company, so it never gets done.
I'll have to ask sometime. I have a feeling that's one of those problems that seems complicated but would have some stupidly simple solution that would make me feel dumb for not thinking of it.
Generating 50 cycle electricity mechanically requires something to spin magnets near conductors at some multiple of 50 hertz.
That would require a complex mechanical drive, which would be both expensive and unreliable.
Instead it would be done with power electronics. MOSFETs and capacitors.
Capacitors are expensive and have a limited life. You replace the power electronics periodically and amortize the replacement cost over every watt generated.
It would be possible to design the power electronics to be reconditioned. That is the way it used to be done in the 60s and 70s. An older design like this would use huge, heavy coils, which last a long time and (depending on the design) can be re-wound.
Yep, for the pinnacle of electro-mechanical systems in this regard, you'd probably be looking at early radio sets - for example the Alexanderson alternator - https://en.wikipedia.org/wiki/Alexanderson_alternator - basically a giant multi-polar generator set up to generate current at VLF frequencies.
And those things were horrendously expensive maintenance nightmares.
I know an engineer that designs the blades and has worked on maintenance in the past too. They actually do use a mechanical system to regulate the speed on most modern windmills. There are brakes as well as mechanisms to adjust the pitch of the blades to gather more/less wind. If you see a bunch of windmills, watch, they are always the same speed.
The blades are mostly fiberglass and balsa wood. I'm not sure that many useful materials could be taken out of them. The posts are steel, but if I had to guess from my own industry they get abandoned in place when they are end of life. It likely costs more to decommission them than the materials are worth, and spending expense $ on such projects looks bad to pretty much any financial report for a public traded company, so it never gets done.
Yeah, the constant-speed thing has been available since ... well, since steam engines, really, hasn't it? The early ones had regulators for that.
Matching the phase of the grid was the major bit of concern, unsure how you'd do that mechanically.
I'll have to ask sometime. I have a feeling that's one of those problems that seems complicated but would have some stupidly simple solution that would make me feel dumb for not thinking of it.
Generating 50 cycle electricity mechanically requires something to spin magnets near conductors at some multiple of 50 hertz.
That would require a complex mechanical drive, which would be both expensive and unreliable.
Instead it would be done with power electronics. MOSFETs and capacitors.
Capacitors are expensive and have a limited life. You replace the power electronics periodically and amortize the replacement cost over every watt generated.
It would be possible to design the power electronics to be reconditioned. That is the way it used to be done in the 60s and 70s. An older design like this would use huge, heavy coils, which last a long time and (depending on the design) can be re-wound.
Yep, for the pinnacle of electro-mechanical systems in this regard, you'd probably be looking at early radio sets - for example the Alexanderson alternator - https://en.wikipedia.org/wiki/Alexanderson_alternator - basically a giant multi-polar generator set up to generate current at VLF frequencies.
And those things were horrendously expensive maintenance nightmares.
I am Imagining one of those built to serve a one megawatt turbine ...
It would be the stuff of legends. I imagine the belts would fly off within the first day.