this post was submitted on 26 Jul 2024
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Discussion of climate, how it is changing, activism around that, the politics, and the energy systems change we need in order to stabilize things.

As a starting point, the burning of fossil fuels, and to a lesser extent deforestation and release of methane are responsible for the warming in recent decades: Graph of temperature as observed with significant warming, and simulated without added greenhouse gases and other anthropogentic changes, which shows no significant warming

How much each change to the atmosphere has warmed the world: IPCC AR6 Figure 2 - Thee bar charts: first chart: how much each gas has warmed the world. About 1C of total warming. Second chart: about 1.5C of total warming from well-mixed greenhouse gases, offset by 0.4C of cooling from aerosols and negligible influence from changes to solar output, volcanoes, and internal variability. Third chart: about 1.25C of warming from CO2, 0.5C from methane, and a bunch more in small quantities from other gases. About 0.5C of cooling with large error bars from SO2.

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Wind turbines rarely fail. So why did Vineyard Wind's fall apart? (grist.org)
submitted 5 months ago by [email protected] to c/[email protected]
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[–] [email protected] 1 points 5 months ago (1 children)

True that, and very well explained I might add.

Now, if I were on their engineering team, I'd probably try a combination of magnetic and roller bearings. Use magnetic bearings to support the weight, while securing everything in place with radial bearings.

That way, the mechanical bearings don't have to support the weight, magnets can take care of most if not all of that, saving undue wear and tear on the mechanical bearings.

I dunno, just a thought.

[–] [email protected] 2 points 5 months ago* (last edited 5 months ago) (1 children)

Actually, magnetic bearings experience wear as well.

So called "permanent" magnets gradually lose their charge over time through interactions with opposing magnetic fields, heat, and mechanical stresses. Neodymium, for example, loses about 0.1% of it's field strength per year even when it isn't being used for anything. This is why you can't use magnets to make perpetual motion machines:

Magnets are basically batteries that store energy in the form of a magnetic field, eventually they run out of charge and need to be re-magnetized.

This makes passive magnetic bearings really tricky to design, so most of those in use are active types that also employ sensors and electromagnets to ensure stability. These electronics also degrade over time, so usually a mechanical bearing is a better choice unless the use-case requires a frictionless axle.

[–] [email protected] 1 points 5 months ago

Everything degrades over time, that's a given, nothing lasts forever. But if they relieve the weight from the mechanical bearings with magnets, then they might last quite a bit longer before needing service.