this post was submitted on 22 May 2024
37 points (91.1% liked)

Climate - truthful information about climate, related activism and politics.

5293 readers
716 users here now

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.

Recommended actions to cut greenhouse gas emissions in the near future:

Anti-science, inactivism, and unsupported conspiracy theories are not ok here.

founded 1 year ago
MODERATORS
top 7 comments
sorted by: hot top controversial new old
[–] NataliePortland@lemmy.ca 5 points 6 months ago (2 children)

There’s a tornado but the turbine is still moving so slow? You’d think they would be capitalizing on all that free wind!!

[–] admiralteal@kbin.social 6 points 6 months ago* (last edited 6 months ago) (1 children)

Those blades are way, way, way bigger than you think they are. They are moving extremely fast even at normal speeds. That 15ish rpm converts to around 1.5 rads/s. Modern windmill blades are something like 70m long -- so we're talking speeds of 100m/s or north of 350 kph / 220 mph.

Pretty comparable speeds to the windspeeds of the tornadoes in question during routine operation. Of course, there's a lot more intensity with a tornado, but windmills are actually designed to let most of the air pass them unimpeded because it makes them work more efficiently.

Of course, their energy production will be deliberately curtailed under high winds because the generators and infrastructure hooking them up can only handle so much -- they'll brake the blades, or rely on back-emf from the motors, or some combination of those factors to prevent them from over-generating.

Of course, unlike typical wind being harvested by the windmills, the tornado's airflow is far from laminar, meaning that even with their highest intensity, they will be losing a lot of efficiency in driving those blades.

...the tornado, of course, will simply knock them down.

[–] NataliePortland@lemmy.ca 3 points 6 months ago

Thank you for the detailed answer. I was really just making a joke, but I still do appreciate how much I have learned here.

[–] sinkingship@mander.xyz 5 points 6 months ago

Usually in a tornado you have a lot of debris flying around. The faster the blades go, the higher the probability to hit debris and damage the expensive blades.

[–] Skanky@lemmy.world 4 points 6 months ago

Is it really that necessary to scream that much? Constantly?

[–] DMCMNFIBFFF 1 points 6 months ago (1 children)
[–] silence7 2 points 6 months ago* (last edited 6 months ago)

There is other footage which shows more going down; scroll down for the lower video.

This is incredibly rare:

Turbines are now built to withstand events like tornadoes, hurricanes and typhoons because of advances in technology since the early designs of the 1990s. They have built-in mechanisms to lock and feather the blades, changing their angles, when winds reach 55 miles per hour. That reduces the surface area of the blades pointed toward the wind.

“You will lose a blade here or a blade there,” during windstorms, Mr. McLachlan said. But a complete knockout is unusual, he said.

I don't think I've seen anything like this since a hurricane took out a whole wind farm in Hawaii in the 1990s. Quite frankly, the loss of homes and lives is a much bigger deal.