Wind power: Difference between revisions
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The best places for wind turbines [[/Geography|aren't usually near where people live]]. In most cases, the distance is far enough that power lines wouldn't even be viable. {{qn}} | The best places for wind turbines [[/Geography|aren't usually near where people live]]. In most cases, the distance is far enough that power lines wouldn't even be viable. {{qn}} | ||
This might not be an issue if | This might not be an issue if hydrogen (as described above) is the main solution for the [[energy storage]]. Instead of power lines, the wind turbines would generate [[hydrogen gas]] which would be [[transportation of hydrogen gas|transported]] and used for [[energy]] elsewhere. | ||
We'd need to estimate the full [[EROI]] of such a system, to make sure it's [[Term:viable|viable]].{{rn}} | We'd need to estimate the full [[EROI]] of such a system, to make sure it's [[Term:viable|viable]].{{rn}} |
Revision as of 16:16, 3 November 2023
Wind power is a possible option for renewable energy.
Wind turbines convert wind to electricity.
A lot of people incorrectly call wind turbines "windmills". But in fact windmills are a much older technology, which use the wind to mill grains mechanically (no electricity involved).
Considerations
#Intermittency | Needs energy storage |
#Geography | Major limitation |
#Rare earth magnets | [RESEARCH needed] |
#Cement | Not a significant problem |
#EROI | Manageable |
#Land use | Manageable |
#Noise | [RESEARCH needed] |
#Recyclability | [RESEARCH needed] |
Intermittency
Wind power is even more intermittent than solar. There can be months where the wind blows strongly, and months where it barely blows at all. Also, wind turbines can't function when the wind blows too hard.
[suitable wind speeds]
Most wind turbines can only generate power when wind speeds are between 3.5 m/s and 25 m/s.
[1]
This intermittency usually gets "filled in" with natural gas power plants, but that's not good enough if we want to phase out fossil fuels.
Having multiple wind farms might somewhat reduce the intermittency. But in practice, this doesn't seem to help much.[2]
Scaling up energy storage is already a challenge, even for solar which only needs about a day's worth of energy storage in general. Wind might need several weeks worth
Maybe wind energy could be stored via hydrogen, which doesn't have a fixed capacity the way batteries do.
Geography
The best places for wind turbines aren't usually near where people live. In most cases, the distance is far enough that power lines wouldn't even be viable. [QUANTIFICATION needed]
This might not be an issue if hydrogen (as described above) is the main solution for the energy storage. Instead of power lines, the wind turbines would generate hydrogen gas which would be transported and used for energy elsewhere.
We'd need to estimate the full EROI of such a system, to make sure it's viable.[RESEARCH needed]
Rare earth magnets
To build a wind turbine
This section needs more research to determine which rare metals are needed, in what quantities, and whether there would be enough global mineral reserves to scale up wind power enough to replace fossil fuels or not.
Cement
The footing of a wind turbine requires a lot of concrete - a potential concern because cement production releases CO2. However, it turns out that the amount of CO2 is not very significant:
McGraw-Hill Encyclopedia of Science and Technology. "Volume generally assumed for the density of hardened concrete is 150 lb/ft^3. (2400 kg/m^3)"
Read more: https://hypertextbook.com/facts/1999/KatrinaJones.shtml
SUSTAINABLE CONCRETE FOR WIND TURBINE FOUNDATIONS www.bnl.gov › isd › documents
"Turbines in the 1 to 2 MW range typically use 130 to 240 m3 of concrete for the foundation"
https://css.umich.edu/factsheets/wind-energy-factsheet
(calculation loading)
Compared to burning gasoline
This is pretty reasonable considering that a wind turbine's lifespan is about 20 years.[3]
EROI
Energy return on investment: About 19.
In other words: wind turbines, over their entire lifespan, produce about 19 times as much energy as it takes to make them.[4] There would still need to be some fossil fuels invested into wind power to "get the ball rolling".
Maybe there are some other wind turbine designs that have a better EROI. [RESEARCH needed]
Land use
Per unit of energy, wind needs far more land than solar
- This is per megawatt capacity (peak), not per average output.
- Stats can vary tremendously based on how windy the location is.
- This stat is based on 172 different wind projects scattered throughout the USA.
- Consider variance: (34.5 +/- 22.4) hectares/MW
- This is the total land use, including the spacing between turbines in a wind farm.
- This is much bigger than [wind.rq_land_disturbed] which is just the land directly impacted by constructing the turbine itself.
Citation:
Land-Use Requirements Of Modern Wind Power Plants In The United States
(Paul Denholm, Maureen Hand, Maddalena Jackson, and Sean Ong)
Page 16
Does not include the fuel used in generating electricity. See [energy.tes] for that.
Citation: "Key World Energy Statistics 2020" IEA
- Page 47 - Simplified energy balance table - World energy balance, 2018
https://css.umich.edu/factsheets/wind-energy-factsheet
(calculation loading)[discussion needed]~ wind.rq_land
is based in the status quo of wind projects, which are probably on land that's more windy than average. If wind turbines were to be on average crop land, the energy productivity may be less. Then again, there's also pasture and barren land where wind turbines could be placed too, and there's also offshore wind. ~ If all countries were developed, we'd need more than just energy.tfc
- but then again, we don't need to get all our energy from wind; rooftop solar also has a lot of productive potential.
There should be no need to destroy natural habitats to build wind farms.
Noise
This section has not been filled in yet.
Recyclability
This section has not been filled in yet.
References
- ↑ DASH, Meteorologically Defined Limits to Reduction in the Variability of Outputs from a Coupled Wind Farm System in the Central US [Online], Available: http://dash.harvard.edu/bitstream/handle/1/10981611/Meteorologically%20defined%20limits%20to%20reduction%20in%20the%20variability%20of%20outputs%20from%20a%20coupled%20wind%20farm%20system%20in%20the%20Central%20US_1.pdf?sequence=6
- ↑ David JC McKay, Sustainable energy - without the hot air [Online], Available: http://www.inference.phy.cam.ac.uk/withouthotair/c26/page_187.shtml
- ↑ United States Environmental Protection Agency (EPA) - Renewable Energy Fact Sheet: Wind Turbines - epa nepis
- ↑ Hall, C., et al. (2013) EROI of different fuels and the implications for society. Energy Policy (64), 141-152.