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>To estimate the impacts of wind power, Keith and Miller established a baseline for the 2012‒2014 U.S. climate using a standard weather-forecasting model. Then,

by chki 8y ago

>To estimate the impacts of wind power, Keith and Miller established a baseline for the 2012‒2014 U.S. climate using a standard weather-forecasting model. Then, they covered one-third of the continental U.S. with enough wind turbines to meet present-day U.S. electricity demand. The researchers found this scenario would warm the surface temperature of the continental U.S. by 0.24 degrees Celsius, with the largest changes occurring at night when surface temperatures increased by up to 1.5 degrees. This warming is the result of wind turbines actively mixing the atmosphere near the ground and aloft while simultaneously extracting from the atmosphere’s motion. I am confused: How does the warming work exactly and is this actually a global climate effect? Because this part of the article makes it sound to me as if it's just a very localised change of temperature caused by the exchange of different air layers, which can't be right? Because you couldn't really compare that to climate change on a global scale.

qaq 8y ago
Given climate fluctuations is 0.24 even meaningful? Also hard to imagine 100% being wind power.
- beat 8y ago
  It's good science to analyze the long tail, even if we will never be on the long tail, because those extreme questions can have meaning in less extreme conditions.
pjc50 8y ago
It is indeed a change in local surface temperature - that is, if you have a thermometer there, it will read 0.24 degrees higher (average across 24h) than it would if there wasn't a nearby wind farm. And yes it's apparently due to atmospheric mixing. I imagine it would have similar effects on crops, evaporation, etc as a global temperature rise. The next question: should this be subtracted from the measurements of any weather station suitably close to a wind farm?
ams6110 8y ago
The example is clearly hypothetical only. We're never going to cover one third of the continental US with wind turbines. The more important information to me is that neither wind nor solar have the power density that has been claimed. For wind, we found that the average power density — meaning the rate of energy generation divided by the encompassing area of the wind plant — was up to 100 times lower than estimates by some leading energy experts ... For solar energy, the average power density (measured in watts per meter squared) is 10 times higher than wind power, but also much lower than estimates by leading energy experts. Then you have the separate problem that the wind doesn't always blow and the sun doesn't always shine, so you need a huge storage infrastructure (batteries, presumably) alongside the wind and solar generating infrastructure. IMO nuclear is the only realistic alternative to coal to provide reliable, zero-emission "base load" power generation. Wind and solar could make sense in some use cases but not in general.
- bilbo0s 8y ago
  >IMO nuclear is the only realistic alternative to coal to provide reliable, zero-emission "base load" power generation... Yeah, but no one wants to pay for it. Which is why you'll see more wind and solar with hydro-storage, and even more geo-thermal energy plants in the future. Even with all the extra infrastructure, it still comes in at less than 2 or 3 cents a kwh long term. Whereas even if you take a very optimistic long term view on nuclear, it's just REALLY hard to get down below 3 cents. So for nuclear sources to get higher in the dispatch stack, government must take on more of the costs. But then, of course, if government is taking on more of the costs, then you're still paying more than 3 cents. Probably a lot more. You'd just pay it in extra taxes instead of a utility bill. So, yeah, I guess that's why energy is a hard problem. No easy solutions really. Just hard to balance pros and cons to every known technology at this point. (Maybe someday someone will figure out this whole fusion thing and we'll be able to consign all these other, less refined, technologies to history's dust bin?)
  - u320 8y ago
    You're not going to be anywhere close to 3 cents in a 100% renewable system without hydro. Cheapest solar price in the US is 2.3 cents but that is in one of the sunniest places in the world, subsidised, and no storage.

by chki 8y ago

qaq 8y ago

Given climate fluctuations is 0.24 even meaningful? Also hard to imagine 100% being wind power.

beat 8y ago
It's good science to analyze the long tail, even if we will never be on the long tail, because those extreme questions can have meaning in less extreme conditions.

pjc50 8y ago

It is indeed a change in local surface temperature - that is, if you have a thermometer there, it will read 0.24 degrees higher (average across 24h) than it would if there wasn't a nearby wind farm. And yes it's apparently due to atmospheric mixing. I imagine it would have similar effects on crops, evaporation, etc as a global temperature rise. The next question: should this be subtracted from the measurements of any weather station suitably close to a wind farm?

ams6110 8y ago

The example is clearly hypothetical only. We're never going to cover one third of the continental US with wind turbines. The more important information to me is that neither wind nor solar have the power density that has been claimed. For wind, we found that the average power density — meaning the rate of energy generation divided by the encompassing area of the wind plant — was up to 100 times lower than estimates by some leading energy experts ... For solar energy, the average power density (measured in watts per meter squared) is 10 times higher than wind power, but also much lower than estimates by leading energy experts. Then you have the separate problem that the wind doesn't always blow and the sun doesn't always shine, so you need a huge storage infrastructure (batteries, presumably) alongside the wind and solar generating infrastructure. IMO nuclear is the only realistic alternative to coal to provide reliable, zero-emission "base load" power generation. Wind and solar could make sense in some use cases but not in general.

bilbo0s 8y ago
>IMO nuclear is the only realistic alternative to coal to provide reliable, zero-emission "base load" power generation... Yeah, but no one wants to pay for it. Which is why you'll see more wind and solar with hydro-storage, and even more geo-thermal energy plants in the future. Even with all the extra infrastructure, it still comes in at less than 2 or 3 cents a kwh long term. Whereas even if you take a very optimistic long term view on nuclear, it's just REALLY hard to get down below 3 cents. So for nuclear sources to get higher in the dispatch stack, government must take on more of the costs. But then, of course, if government is taking on more of the costs, then you're still paying more than 3 cents. Probably a lot more. You'd just pay it in extra taxes instead of a utility bill. So, yeah, I guess that's why energy is a hard problem. No easy solutions really. Just hard to balance pros and cons to every known technology at this point. (Maybe someday someone will figure out this whole fusion thing and we'll be able to consign all these other, less refined, technologies to history's dust bin?)
- u320 8y ago
  You're not going to be anywhere close to 3 cents in a 100% renewable system without hydro. Cheapest solar price in the US is 2.3 cents but that is in one of the sunniest places in the world, subsidised, and no storage.