Harnessing the power of hurricanes

[ScienceNostalgia101]

Inspired by my own thread on forest fires.

 

https://energyeducation.ca/encyclopedia/Betz_limit

 

So basically, the Betz limit suggests that a theoretical maximum of 59.3% of energy could be extracted from wind at a time. That leaves 40.7% or more still in the wind.

 

So, wind retains at least 0.407 times its maximum energy; which, by E=mvv/2, suggests it retains 0.638 of its speed. Does that mean that with a long enough row of closely-packed, highly-efficient wind turbines designed to handle hurricane-force winds, you could reduce the wind speeds from 120 km/h to about 77km/h, storing the excess energy until the power lines are repaired?

 

Alternatively, what if one build a GIANT wind turbine... and/or made it horizontal instead of vertical. (Ie. Flat to the surface... or close-to-flat, given Earth's curvature.) If it were hundreds of kilometres wide, would any hurricane that passed through it turn horizontally aligned blades and convert the kinetic energy to storable electrical energy that way?

Edited August 12, 2018 by ScienceNostalgia101

[John Cuthber]

Hurricanes + forest fires have similar problems. They are rare, and you don't know where they will happen.
Also they produce so much energy that it's difficult for us to consider controlling it.

 

[Phi for All]

https://www.forbes.com/sites/jenniferhicks/2012/11/06/cubas-two-wind-farms-survive-hurricane-sandy/#3bfa8f267ad1

Quote

Before Hurricane Sandy hit the East Coast of the US, she actually hit the Caribbean first. Two of the hardest hit islands were Haiti and Cuba. Thousands of houses were destroyed in the Eastern part of Cuba around Santiago de Cuba, the country's second largest city, and power supplies in the area were and still are affected by the hurricane.

However, in the province of Holguín, there were two wind farms installed in 2008 and 2010 one with six 850 kW turbines and the other with six 750 kW machines. Both of those wind farms were hit by hurricane Sandy with wind speeds of up to 110 miles per hour and neither of them had any major damage and continued to provide electricity for the local grid.

 

[mistermack]

Once you've harnessed it, what do you do with it? 

Find a way to STORE wind energy cost-effectively and you can order your yacht.

[Phi for All]

8 minutes ago, mistermack said:

Once you've harnessed it, what do you do with it? 

Find a way to STORE wind energy cost-effectively and you can order your yacht.

https://www.scientificamerican.com/article/wind-power-turbine-storage-electricity-appliances/

Quote

Wind farms typically generate most of their energy at night, when most electricity demand is lowest. So a lot of that "green" energy is wasted.

So the big question is: How do you bottle that power for air conditioners and other appliances that are busiest during the day?

There are many companies moving to fill the energy gap. Using federal loan guarantees and $4 billion in "smart grid" stimulus cash, they are working on utility-scale storage units that they hope will help balance intermittent renewable sources like wind and solar and let electric grid operators match power supplies with demand.

It's being done. If people stop looking at each renewable as non-viable, and looked at solar/wind/geothermal together, they'd see we're already cost-effective enough to move away from fossil fuels fairly quickly.

[mistermack]

15 minutes ago, Phi for All said:

https://www.scientificamerican.com/article/wind-power-turbine-storage-electricity-appliances/

It's being done. If people stop looking at each renewable as non-viable, and looked at solar/wind/geothermal together, they'd see we're already cost-effective enough to move away from fossil fuels fairly quickly.

Yeh, I'm aware of the potential and keen to see progress. Flywheels have a lot of potential, but I don't think the economics is there as yet. Going from memory, they are very good, for projects that need a lot of power in a hurry, like fusion research etc. But it's money that makes the world go round. If they get profitable, people will dive in. It's frustrating that most methods seem to be only just economic, with the right subsidies and grants. But like I said, find one that's CLEARLY economic, and you can order the yacht and start learning to sail.

[Phi for All]

36 minutes ago, mistermack said:

If they get profitable, people will dive in. It's frustrating that most methods seem to be only just economic, with the right subsidies and grants.

Actually, solar is so efficient now that the electricity produced by it is too cheap to attract people interested in maximum profit. This is why private solar companies will never be the solution. The most efficient thing we could do now is develop a public solar and wind utility to flood the market with cheap, not-for-profit based electricity. MANY manufacturing opportunities could become reality for investors if powering your products is no problem.

Frankly, I'm sick of private businesses that need public subsidies in order to turn the profit their stockholders want.

[mistermack]

There are states that don't need to rely on private enterprise though, and they don't have a great record. If any country has a chance of doing what you suggest, it's China, as those in charge can take direct control if they want. 

They also have the incentive, with mainly dirty fossil fuel reserves, and pollution problems. So it's most likely that the biggest developments will be coming from there.

[Phi for All]

21 minutes ago, mistermack said:

There are states that don't need to rely on private enterprise though, and they don't have a great record.

Do you have any data on that, or are you relying on what private utilities tell you about public utilities of the past? In my experience, we had plenty of electricity and natural gas from our public utility, and now we get to pay 40% more (adjusted for inflation) since it was deregulated and purchased by a private company. 

[StringJunky]

1 hour ago, Phi for All said:

Actually, solar is so efficient now that the electricity produced by it is too cheap to attract people interested in maximum profit. This is why private solar companies will never be the solution. The most efficient thing we could do now is develop a public solar and wind utility to flood the market with cheap, not-for-profit based electricity. MANY manufacturing opportunities could become reality for investors if powering your products is no problem.

Frankly, I'm sick of private businesses that need public subsidies in order to turn the profit their stockholders want.

I can see solar panels being on almost every new build roof .Autonomy of energy supply is the way to go... when the domestic battery storage is cheap enough. I think the newly developed photovoltaic stuff is embedded in plastic film that can be wrapped around or laid out on anything. 

[mistermack]

1 hour ago, Phi for All said:

Do you have any data on that, or are you relying on what private utilities tell you about public utilities of the past? In my experience, we had plenty of electricity and natural gas from our public utility, and now we get to pay 40% more (adjusted for inflation) since it was deregulated and purchased by a private company. 

I'm not arguing for private enterprise, I'm not a fan of it for monopolies. But public ownership has it's problems too. 

I can't speak for the US, but in the UK, it's the unions that are the problem. (in my opinion). Public ownership gives them huge power to hold the country to ransom, and that's why the UK has historically split the sector up into myriads of private companies. Fragment and rule seems to be the tactic. We've had the UK working a 3 day week in the past, during a miners strike. And power generation unions have had similar power in the past. 

I can't see why they can't draft laws to control it, but there doesn't seem any appetite over here to go back to increased public ownership. We had a gut full in the sixties and seventies and eighties. And we still have similar problems with firefighter unions and train drivers. Anywhere where people have a monopoly, they like to turn the screw, on both sides of industry.

But really, the ownership doesn't affect how the economics of the various technologies stack up against each other.

[J.C.MacSwell]

4 hours ago, Phi for All said:

https://www.forbes.com/sites/jenniferhicks/2012/11/06/cubas-two-wind-farms-survive-hurricane-sandy/#3bfa8f267ad1

 

"However, in the province of Holguín, there were two wind farms installed in 2008 and 2010 one with six 850 kW turbines and the other with six 750 kW machines. Both of those wind farms were hit by hurricane Sandy with wind speeds of up to 110 miles per hour and neither of them had any major damage and continued to provide electricity for the local grid."

Am I going out on a limb suggesting they were probably shut down during the storm , not damaged, and then restarted afterward?

[Phi for All]

2 hours ago, J.C.MacSwell said:

Am I going out on a limb suggesting they were probably shut down during the storm , not damaged, and then restarted afterward?

Way out. From what I read, the wind farms were designed to run in hurricane mode. Even this article mentions the turbines were still running and providing power with 110 mph winds.

[J.C.MacSwell]

8 minutes ago, Phi for All said:

Way out. From what I read, the wind farms were designed to run in hurricane mode. Even this article mentions the turbines were still running and providing power with 110 mph winds.

Where did you read it? (I know the quote implies it, but could be taken as a little ambiguous)

From a quick search:

https://www.windpowermonthly.com/article/1161711/turbines-left-broadly-unaffected-hurricane-sandy

"Sandy was a category 2 hurricane as it tore through the Caribbean and ripped into Cuba on 25 October, with winds of nearly 50 metres per second (m/s). Two small wind projects in Cuba's hard-hit Holguin province were not seriously damaged and were soon providing electricity again to the grid, the government reported."

[Phi for All]

8 hours ago, J.C.MacSwell said:

Where did you read it? (I know the quote implies it, but could be taken as a little ambiguous)

Most of these articles we're seeing mention that the wind farms can be switched to "hurricane mode", which generates less electricity but "soon provides" full power again.

https://yes2renewables.org/2014/01/20/wind-turbines-survive-hurricanes-what-a-blow-to-doubters/

Quote

 

On the afternoon of October 28, the Jersey Atlantic Wind Project stood right in Sandy’s projected path, and authorities at Infigen, which operates the five turbines just outside Atlantic City, weren’t quite sure what to expect. No other U.S. wind turbine project has taken a direct hit from a tropical storm of Sandy’s strength.

But the operators punched a few keystrokes on their computers, put the turbines into “hurricane mode,” and hoped for the best. They got it. Sandy’s wind speeds dropped below hurricane status just before landfall, but the Infigen turbines still withstood sustained winds of 65 mph [105 kph] or so, with gusts reaching much higher, as the center of Sandy passed right over them. The turbines were undamaged, said Matthew McGowan of Infigen, and were soon generating 1.5 megawatts of electricity again.

 

This study also implies that wind farms operate during hurricanes, since leaving them on removes energy from the storm.

http://www.climatecentral.org/news/offshore-wind-farms-could-protect-cities-from-hurricanes-16813

Quote

They concluded that the wind turbines could have sapped Katrina of so much energy that wind speeds would have been reduced by up to 50 percent at landfall and the hurricane's storm surge could have been reduced by about 72 percent, Jacobson said. It also would have generated 0.45 terawatts of wind power.

 

[Sensei]

@Phi for All@J.C.MacSwell

 

https://www.energy.gov/eere/articles/wind-turbines-extreme-weather-solutions-hurricane-resiliency

"Recent hurricanes Irma and Maria inflicted a lot of damage on infrastructure, including energy infrastructure. Wind turbines, whether they are land-based or offshore, have built-in mechanisms to lock and feather the blades (reducing the surface area that’s pointing into the wind) when wind speeds exceed 55 miles per hour. Basically, the wind turbine is essentially in “survival mode,” waiting for the storm to subside, so it can safely go back to producing energy."

https://www.energy.gov/eere/articles/how-do-wind-turbines-survive-severe-storms

"Every wind turbine has an anemometer that measures wind speed and a wind vane to keep track of the wind’s direction. See if you can find them toward the end of the scene of this 360° Wind Turbine Tour video.

When the anemometer registers wind speeds higher than 55 mph (cut-out speed varies by turbine), it triggers the wind turbine to automatically shut off. "

 

[zapatos]

This article seems to suggest that turbines shut down in hurricanes.

Quote

The diagram below shows the power output of a turbine against steady wind speeds. The cut-in speed (typically between 6 and 9 mph) is when the blades start rotating and generating power. As wind speeds increase, more electricity is generated until it reaches a limit, known as the rated speed. This is the point that the turbine produces its maximum, or rated power. As the wind speed continues to increase, the power generated by the turbine remains constant until it eventually hits a cut-out speed (varies by turbine) and shuts down to prevent unnecessary strain on the rotor.

https://www.energy.gov/eere/articles/how-do-wind-turbines-survive-severe-storms

Edit: Cross posted with Sensei

Edited August 13, 2018 by zapatos

[J.C.MacSwell]

22 minutes ago, Phi for All said:

Most of these articles we're seeing mention that the wind farms can be switched to "hurricane mode", which generates less electricity but "soon provides" full power again.

https://yes2renewables.org/2014/01/20/wind-turbines-survive-hurricanes-what-a-blow-to-doubters/

This study also implies that wind farms operate during hurricanes, since leaving them on removes energy from the storm.

http://www.climatecentral.org/news/offshore-wind-farms-could-protect-cities-from-hurricanes-16813

 

"Hurricane mode" is feathered (not turning and not producing power) so as not to expose the blades to 8 times times the energy going through the disc for every doubling of wind speed.

From your quote:

"Sandy’s wind speeds dropped below hurricane status just before landfall, but the Infigen turbines still withstood sustained winds of 65 mph [105 kph] or so, with gusts reaching much higher, as the center of Sandy passed right over them. The turbines were undamaged, said Matthew McGowan of Infigen, and were soon generating 1.5 megawatts of electricity again."

As impressive as this might sound, they were feathered/not turning at the 65mph quoted...which is barely over 1/5 of the wind energy going through the disc than it would be at the 110mph wind speed claimed by the writer of your original post for the Cuban turbines.

Edited August 13, 2018 by J.C.MacSwell

[Phi for All]

Well thanks for the corrections, all.

I suppose it's not enough that they survive when other forms of power generation fail. To be considered viable, apparently they need to be able to operate fully in all weather before folks appreciate them fully. What a shame these limited devices have to "feather" (sounds like a snowflake thing to do) and can't operate at full capacity during a hurricane!

[Sensei]

@Phi for All

There is alternative design, vertical axis wind turbine.

https://en.wikipedia.org/wiki/Vertical_axis_wind_turbine

There should be made experimental offshore field of traditional wind turbines, mixed with vertical wind turbines, and performed experiment how well they will survive/behave in hurricanes/storms.

If test will prove they are better in such unfriendly weather environment, they should be used instead of traditional design.

 

[zapatos]

4 minutes ago, Phi for All said:

Well thanks for the corrections, all.

I suppose it's not enough that they survive when other forms of power generation fail. To be considered viable, apparently they need to be able to operate fully in all weather before folks appreciate them fully. What a shame these limited devices have to "feather" (sounds like a snowflake thing to do) and can't operate at full capacity during a hurricane!

It would be surprising to me if the only thing keeping someone from considering wind turbines "viable" is that they don't shut down for that fraction of time during its life when a hurricane is hitting it.

[J.C.MacSwell]

3 minutes ago, Sensei said:

@Phi for All

There is alternative design, vertical axis wind turbine.

https://en.wikipedia.org/wiki/Vertical_axis_wind_turbine

There should be made experimental offshore field of traditional wind turbines, mixed with vertical wind turbines, and performed experiment how well they will survive/behave in hurricanes/storms.

If test will prove they are better in such unfriendly weather environment, they should be used instead of traditional design.

 

Interesting (though no doubt expensive) idea as you might match the power of the mix to maintain the grid power the field normally generates, effectively at least for smaller hurricanes.

[mistermack]

Feathering would of course reduce the load on the main bearings, but not to zero, so it would make sense to not have it turning while such a big load is going through it. And of course, with a hurricane blowing, it's not a bad thing to have no power going through the cables till it's blown over. It's still impressive that they could run afterwards. 

I can't really see a wind farm making much of a dent in a hurricane's power. Even the biggest turbines only reach 700 feet at the top, whereas a hurricane can be the size of France, and reach an altitude of about 45,000 feet...

[ScienceNostalgia101]

On 8/13/2018 at 10:54 AM, Sensei said:

@Phi for All

There is alternative design, vertical axis wind turbine.

https://en.wikipedia.org/wiki/Vertical_axis_wind_turbine

There should be made experimental offshore field of traditional wind turbines, mixed with vertical wind turbines, and performed experiment how well they will survive/behave in hurricanes/storms.

If test will prove they are better in such unfriendly weather environment, they should be used instead of traditional design.

 

You mean something like this?

 

 

That's kind of what I had in mind when I said "horizontal instead of vertical." I didn't mean the axis was horizontal, I meant the blades, instead of going up and down, went from N to E to S to W... or in the other direction, depending upon how the hurricane approaches it.

 

As for other wind turbines, even if they have to shut down for full-blown hurricanes, doesn't that still mean they can sap the energy of developing hurricanes? (Ie. Ones that haven't yet achieved hurricane force winds but might not at all if wind turbines sap their energy sooner?)

Edited August 16, 2018 by ScienceNostalgia101

[ScienceNostalgia101]

Bumping because of Hurricane Lane. (It's been a week and a day since the other post.)

 

Another question now; if they had enough rows of offshore wind turbines, harvesting about 3/5 of the wind energy at every row, would they be able to prevent hurricanes from forming in the first place?