Formula One comes to Wind Turbines

[NickW + 2,714]

https://www.anakatawindpower.com/

Interesting. Formula One design comes to wind power. Winglets and aerofoils bring 10% performance improvements. Can be retrofitted to existing turbines with a payback period of 2 years. 

Retrofitting the entire global fleet could add 90-100 TWh to annual output from wind. 

 

[footeab@yahoo.com + 2,187]

Just 100% no.  These guys are abject ignorant fools.  I was in the industry for several years.  If turbines were not mounted on a tower and it was not spinning then they would be correct. But, wind turbines are mounted on a tower, it is spinning, and surface roughness of the landscape matters. 

Wind turbine limits are due to RPM*mass = tensile loads, and tower loads.  Instead of increasing torque and increasing tower load, increase tower height and create a higher CF while keeping the construction process easy and simple assuming you have the excess tower capacity. 

The reason higher lift is NOT used on wind turbines is because POWER = torque(lift) x RPM, but to create this extra lift always creates a DRAG penalty = tower forces.  Now high lift devices such as gurney flaps etc could probably be built on the ocean turbines as their pedestal rotor height is not as high as those on land and therefore the tower forces are lower.  Likewise they do not care about thrown ice chunks weighing a ton(literally)

What these F1 ignorants have not taken into account is ICE.  All those VG's, serrated edges HOLD ice.  This is a MASSSIVE, MASSIVE NO NO NO NO NO NO!!!!    Even normal smooth skinned turbines can easily build up several cm of ice  and when it lets loose literally a TON of ice can be shed and thrown a half kilometer.  This ice thrown also creates MASSIVE insanely large dynamic vibration loads at the rotor hub which destroys the bearings.  Adding VG's while excellent for beautiful blue sky conditions is horrific under ice conditions on a spinning mass.  On a straight wing wing, it just means higher ice loads and can be dealt with by flying into/out of clouds or landing.  No such options for a wind turbine and no, heating the leading edges is not viable on a wind turbine.  We looked into a mechanical "flexing solution" to shed ice but could not adequately make it work over long periods of time without damaging the structure. 

For these SAME ice load condition problems slats/flaps have not been installed on wind turbines even though under sunny blue sky conditions for lower wind speed days they would be AWESOME.  Slats/flaps have crevices, etc and hold ICE.  LIkewise those crevices etc FREEZE up and then you have the problem of ONE side, or part of ONE side deploying flaps while the other blades are frozen shut or vice versa. 

Likewise their winglets due to iceing are also a gigantic  NO GO!  1 ton of ice traveling at 200 km/h hitting the winglet... uh yea, not going to be a happy day. 

Wind turbine guys are not stupid.  There is nothing new about winglets, VG, serrated edges.  These have all been around for going on a hundred years now.  Just stupid F1 boys finally found out about this stuff a couple decades ago and now think they are hot stuff. 

EDIT: PS: Find some wind turbines that are guaranteed to NOT have icing problems then don't bother with this half assed approach, build in slats, flaps permanently or semi permanently for the large number of low wind speed days.... of course once again... this assumes the tower is free(oh wait, it is not and is the costliest portion as higher height = higher CF and entire problem of wind is intermittency/variability which is easiest solved by greater tower height)

PPS: Everyone is working on deicing solutions.  Many claim to have them, but only work in VERY mild icing conditions such as Vestas blown hot air. 

Edited December 21, 2019 by footeab@yahoo.com

[NickW + 2,714]

2 hours ago, footeab@yahoo.com said:

Just 100% no.  These guys are abject ignorant fools.  I was in the industry for several years.  If turbines were not mounted on a tower and it was not spinning then they would be correct. But, wind turbines are mounted on a tower, it is spinning, and surface roughness of the landscape matters. 

Wind turbine limits are due to RPM*mass = tensile loads, and tower loads.  Instead of increasing torque and increasing tower load, increase tower height and create a higher CF while keeping the construction process easy and simple assuming you have the excess tower capacity. 

The reason higher lift is NOT used on wind turbines is because POWER = torque(lift) x RPM, but to create this extra lift always creates a DRAG penalty = tower forces.  Now high lift devices such as gurney flaps etc could probably be built on the ocean turbines as their pedestal rotor height is not as high as those on land and therefore the tower forces are lower.  Likewise they do not care about thrown ice chunks weighing a ton(literally)

What these F1 ignorants have not taken into account is ICE.  All those VG's, serrated edges HOLD ice.  This is a MASSSIVE, MASSIVE NO NO NO NO NO NO!!!!    Even normal smooth skinned turbines can easily build up several cm of ice  and when it lets loose literally a TON of ice can be shed and thrown a half kilometer.  This ice thrown also creates MASSIVE insanely large dynamic vibration loads at the rotor hub which destroys the bearings.  Adding VG's while excellent for beautiful blue sky conditions is horrific under ice conditions on a spinning mass.  On a straight wing wing, it just means higher ice loads and can be dealt with by flying into/out of clouds or landing.  No such options for a wind turbine and no, heating the leading edges is not viable on a wind turbine.  We looked into a mechanical "flexing solution" to shed ice but could not adequately make it work over long periods of time without damaging the structure. 

For these SAME ice load condition problems slats/flaps have not been installed on wind turbines even though under sunny blue sky conditions for lower wind speed days they would be AWESOME.  Slats/flaps have crevices, etc and hold ICE.  LIkewise those crevices etc FREEZE up and then you have the problem of ONE side, or part of ONE side deploying flaps while the other blades are frozen shut or vice versa. 

Likewise their winglets due to iceing are also a gigantic  NO GO!  1 ton of ice traveling at 200 km/h hitting the winglet... uh yea, not going to be a happy day. 

Wind turbine guys are not stupid.  There is nothing new about winglets, VG, serrated edges.  These have all been around for going on a hundred years now.  Just stupid F1 boys finally found out about this stuff a couple decades ago and now think they are hot stuff. 

EDIT: PS: Find some wind turbines that are guaranteed to NOT have icing problems then don't bother with this half assed approach, build in slats, flaps permanently or semi permanently for the large number of low wind speed days.... of course once again... this assumes the tower is free(oh wait, it is not and is the costliest portion as higher height = higher CF and entire problem of wind is intermittency/variability which is easiest solved by greater tower height)

PPS: Everyone is working on deicing solutions.  Many claim to have them, but only work in VERY mild icing conditions such as Vestas blown hot air. 

There seems to be plenty of studies out their supporting the use of winglets to increase power output. 

Taking that you are correct on the icing issue there are plenty of turbines around the world operating in ice free conditions. 

[footeab@yahoo.com + 2,187]

27 minutes ago, NickW said:

There seems to be plenty of studies out their supporting the use of winglets to increase power output. 

Taking that you are correct on the icing issue there are plenty of turbines around the world operating in ice free conditions. 

Winglets for a wind turbine... depends what one means by winglet.  Most have them already and have done so for several decades.  Winglets are used to decrease induced drag.  Wind turbines work at low CL, and exceedingly high AR, so winglets will not help much other than noise reduction(not insignificant) as this means one may be able to site said turbine closer to homes or increase RPM. 

If someone can create a RELIABLE(most are not reliable and unbalanced blades are an even WORSE problem), cheap solution to de-icing, then northern turbines(vast majority in the world) can run during winter when often they are idled due to icing problems.  Lobbing a half or 1 ton block of ice through someones house is not exactly a welcome Christmas present. 

Obviously if someone can figure out the icing problems, then adding on LE slats, VG's, flaps, massively increasing CL for low wind speed days(common) then what most consider winglets, will become more useful.

[NickW + 2,714]

1 hour ago, footeab@yahoo.com said:

Winglets for a wind turbine... depends what one means by winglet.  Most have them already and have done so for several decades.  Winglets are used to decrease induced drag.  Wind turbines work at low CL, and exceedingly high AR, so winglets will not help much other than noise reduction(not insignificant) as this means one may be able to site said turbine closer to homes or increase RPM. 

If someone can create a RELIABLE(most are not reliable and unbalanced blades are an even WORSE problem), cheap solution to de-icing, then northern turbines(vast majority in the world) can run during winter when often they are idled due to icing problems.  Lobbing a half or 1 ton block of ice through someones house is not exactly a welcome Christmas present. 

Obviously if someone can figure out the icing problems, then adding on LE slats, VG's, flaps, massively increasing CL for low wind speed days(common) then what most consider winglets, will become more useful.

Which is why in most countries planning laws stipulate minimum distances between houses and the turbines. Also mitigates potential noise complaints. 

 

I understand all modern turbine blades deployed in temperate and cold climates have wire heater elements in the blades and sensors to switch them on and off as needed. 

Edited December 21, 2019 by NickW

[footeab@yahoo.com + 2,187]

5 hours ago, NickW said:

I understand all modern turbine blades deployed in temperate and cold climates have wire heater elements in the blades and sensors to switch them on and off as needed. 

Which is what everyone has been doing for a long time.  And... It works until it doesn't.  It is the failure modes which are the problem. 

Failure mode: Winter storm blowing 60kmh, massive icing conditions, turn on system right?  Right.  Now your turbine is cranking max power, max RPM, stopping it in a 60kmh is well.... near impossible, and say one portion of your electric deicing turbine blade fails and lets assume your sensor for current actually catches it(assuming you have such a failure mode system)....  You are still up Shit creek without a paddle.  You then have to be able to shut down equally the other blades sections as well, switching sensors etc.  It is why pumped hot air is usually tried since if the hot air blower dies, or heating element dies, all 3 blades stop receiving hot air equally which means your entire rotor hub bearing is not scrapped(whole turbine at that point) due to dynamic massive vibration due to deicing imbalance.  Of course hot air blowers have the drastic problem of pumping cold by the time the outer reaches of blade the hot air is passed over meaning ice build up at extreme edge which creates the worst problems.  Which correspondingly means the temp near root has to be VERY high which means titanium/steel conduit to hold the hot air so your fiberglass, carbon resin matrix's do not go through glass transition temperature, or creep temp. 

Yes, both the 787/A350 use embedded resistive elements in their leading edges.  In their Aluminum leading edges, not fiberglass.  Boeing tried going with a heating blanket and using carbon fiber leading edge slats.  Failed due to weight/efficiency problems.  Not sure in the A350's case.  Weight as a driving factor is a larger problem on a giant wind turbine due to moment of inertia increasing by the square of radial distance unlike an airplane stationary wing.   

Not an easy problem: If you have extra tensile load available, do you increase blade length and then power collected goes UP by the SQUARE of extra length to operate ALL of the year, or do you put tons of weight into deicing so you can operate during a couple winter months at a reduced power output(shorter blades + dumping bucket loads of power into heating + much greater up front costs and increased installation time, thus your ROI is.......  All about the ROI.  I have not done current trade off $$$/CF study in a couple decades now for wind turbines, but when we did the cost based analysis, our conclusion was put all that weight into greater blade diameter or put that $$$ into increased tower hub height.  Increased tower hub height won. 

[Douglas Buckland + 6,308]

Damn! Footy seems to really know what he’s talking about! What a welcome change.

I had never even considered the effects of icing on these windmills!

[footeab@yahoo.com + 2,187]

3 hours ago, Douglas Buckland said:

Damn! Footy seems to really know what he’s talking about! What a welcome change.

I had never even considered the effects of icing on these windmills!

Yea.  Spent most of my life in the Aeronautics side of engineering.  Only recently have I started a side business in O&G services support side of things and it shows eh?  😃 

PS: Surprised someone hasn't gone with "biplane" wind turbine.  Would solve quite a few problems.  Creates others of course, but... no one is brave enough to be first. 

[Ward Smith + 6,615]

19 hours ago, footeab@yahoo.com said:

Which is what everyone has been doing for a long time.  And... It works until it doesn't.  It is the failure modes which are the problem. 

Failure mode: Winter storm blowing 60kmh, massive icing conditions, turn on system right?  Right.  Now your turbine is cranking max power, max RPM, stopping it in a 60kmh is well.... near impossible, and say one portion of your electric deicing turbine blade fails and lets assume your sensor for current actually catches it(assuming you have such a failure mode system)....  You are still up Shit creek without a paddle.  You then have to be able to shut down equally the other blades sections as well, switching sensors etc.  It is why pumped hot air is usually tried since if the hot air blower dies, or heating element dies, all 3 blades stop receiving hot air equally which means your entire rotor hub bearing is not scrapped(whole turbine at that point) due to dynamic massive vibration due to deicing imbalance.  Of course hot air blowers have the drastic problem of pumping cold by the time the outer reaches of blade the hot air is passed over meaning ice build up at extreme edge which creates the worst problems.  Which correspondingly means the temp near root has to be VERY high which means titanium/steel conduit to hold the hot air so your fiberglass, carbon resin matrix's do not go through glass transition temperature, or creep temp. 

Yes, both the 787/A350 use embedded resistive elements in their leading edges.  In their Aluminum leading edges, not fiberglass.  Boeing tried going with a heating blanket and using carbon fiber leading edge slats.  Failed due to weight/efficiency problems.  Not sure in the A350's case.  Weight as a driving factor is a larger problem on a giant wind turbine due to moment of inertia increasing by the square of radial distance unlike an airplane stationary wing.   

Not an easy problem: If you have extra tensile load available, do you increase blade length and then power collected goes UP by the SQUARE of extra length to operate ALL of the year, or do you put tons of weight into deicing so you can operate during a couple winter months at a reduced power output(shorter blades + dumping bucket loads of power into heating + much greater up front costs and increased installation time, thus your ROI is.......  All about the ROI.  I have not done current trade off $$$/CF study in a couple decades now for wind turbines, but when we did the cost based analysis, our conclusion was put all that weight into greater blade diameter or put that $$$ into increased tower hub height.  Increased tower hub height won. 

Hmm, my friend's airplane had inflatable "boots". All weather capability (also heaters in the propeller). Where on the turbines does the ice accumulate? I'd guess leading edges but until five minutes ago I never spent one minute thinking about it. 

[footeab@yahoo.com + 2,187]

1 minute ago, Ward Smith said:

Hmm, my friend's airplane had inflatable "boots". All weather capability (also heaters in the propeller). Where on the turbines does the ice accumulate? I'd guess leading edges but until five minutes ago I never spent one minute thinking about it. 

Yes, leading edge if operating, but the problem is a bit different as often no wind fog conditions create icing on whole turbine.  Then you also have the problem of the no wind ice rain which runs down the bottom blade creating massive ice buildup on bottom blade tip compared to the "up" blades creating massive balance problem.  Big airplanes have deicing sheds where whole wing is pressure washed... I do not see any pressure washers on turbines....

[Jan van Eck + 7,558]

You could bnuild a propeller blade that had a tube running down the center, then a large series of little side runs with weep holes.  Then at the center part there is this pump that pushes vast quantities of industrial alcohol out through the tubes to soak the entire blade in alcohol, to prevent the ice buildup.  That would certainly rejuvenate the alcohol market, for sure!

Or perhaps the better approach is to forget all that and go back to sailcloth blades, as they had 500 years ago in Holland.  The windmill has four blades, with each a cross-hatch backing frame, and then a sailcloth that unfurls over the backing to be the turning force.  The sailcloth acts the same as a sail on a sailboat, with a pressure differential across the front and back.

Edited December 23, 2019 by Jan van Eck

[NickW + 2,714]

18 hours ago, footeab@yahoo.com said:

Yes, leading edge if operating, but the problem is a bit different as often no wind fog conditions create icing on whole turbine.  Then you also have the problem of the no wind ice rain which runs down the bottom blade creating massive ice buildup on bottom blade tip compared to the "up" blades creating massive balance problem.  Big airplanes have deicing sheds where whole wing is pressure washed... I do not see any pressure washers on turbines....

Isn't this why cold and temperate climates are built with control software that turns the rotor slowly (1-2 rpm) in still conditions to prevent uneven ice build up?

and the manufacturers have cold option packs for their turbines. 

Ex is Vestas. I'm sure Siemens, GE, Nordex, Enercon etc have similar option packages. 

https://www.vestas.com/en/products/options_and_solutions#!vestas-cold-climate-solutions

[Ward Smith + 6,615]

1 hour ago, NickW said:

Isn't this why cold and temperate climates are built with control software that turns the rotor slowly (1-2 rpm) in still conditions to prevent uneven ice build up?

and the manufacturers have cold option packs for their turbines. 

Ex is Vestas. I'm sure Siemens, GE, Nordex, Enercon etc have similar option packages. 

https://www.vestas.com/en/products/options_and_solutions#!vestas-cold-climate-solutions

Hmm, so when it's cold and the wind isn't blowing, the turbines consume energy to keep the blades turning fast enough to dissuade ice from forming? Am I missing anything here? No wonder Trump admitted he didn't understand wind energy. I'm guessing if more people knew more about it, they wouldn't understand either.  

[NickW + 2,714]

4 minutes ago, Ward Smith said:

Hmm, so when it's cold and the wind isn't blowing, the turbines consume energy to keep the blades turning fast enough to dissuade ice from forming? Am I missing anything here? No wonder Trump admitted he didn't understand wind energy. I'm guessing if more people knew more about it, they wouldn't understand either.  

That small energy consumption is deducted off the turbines net annual electricity production. 

[footeab@yahoo.com + 2,187]

2 hours ago, NickW said:

Isn't this why cold and temperate climates are built with control software that turns the rotor slowly (1-2 rpm) in still conditions to prevent uneven ice build up?

and the manufacturers have cold option packs for their turbines. 

Ex is Vestas. I'm sure Siemens, GE, Nordex, Enercon etc have similar option packages. 

https://www.vestas.com/en/products/options_and_solutions#!vestas-cold-climate-solutions

No.  Slow RPM just means not enough wind to produce power, but they(the operators) think wind will pick up and therefore let the turbine free wheel so when the wind does pick up, the turbine will already be close to operating condition.   Otherwise the turbines are locked down(brakes), turned out of the expected wind direction, with blades set rotated in "spoiler mode". 

Deicing systems... everyone has had them for very long time, pulled directly off the civilian aircraft industry and they do not work under operating conditions unless an absolutely god smacking amount of power is dumped.  On a civilian aircraft they have engines producing immense amounts of waste heat so they just piped it.  Turbines have gotten good enough less and less waste heat to the point where imbedded electrical resistive wires are used, but then only in extreme conditions where the #1 deicing system is CLIMB out of the damned clouds, or Descend.  The blown hot air is just literally a back up.  On a civilian airliner the only true part which has a true deicing system are the pitot tubes(all 5 of them).  Now back to a spinning blade and de icing: It is ONLY to be used at full stop once the storm has blown through and icing conditions are not present so they can resume normal operation.    Otherwise, you can easily pick up a couple centimeters of ice in a matter of a couple of 10s of minutes due to spinning through the gunk.  Why I mentioned the active flexing solution I was part of and working on.  We were trying for an active system that would work WHEN it was operating. 

[Ward Smith + 6,615]

Found CNN hatchet job and wanted to address it here

Quote

Trump referred to wind turbines as "a bird graveyard" telling the crowd that if they "go under a windmill someday, you'll see more birds than you've ever seen ever in your life." 

Facts First: Research suggests that while wind power does contribute to bird deaths, more birds are killed by cats or other types of power plants.

So, "facts first" can't address the argument, but like a lot of folks here, plays whataboutism instead. Plus I'd add the types cats kill are primarily little garbage birds that are non native and over populous. Not like cats kill eagles and owls who are attracted to the carnage from those cuisanarts of the sky. 

Then there's something about eagles and facts first  CNN wants us to ignore their last paragraph. It was also interesting to discover they get to kill 4200 eagles. 

Quote

Trump claimed that wind turbines leave a large carbon footprint, specifically that the manufacturing of wind turbines results in "tremendous amount of fumes and everything." 

Facts First: Wind power has the smallest carbon footprint compared to other energy sources, according to the Department of Energy. A 2014 study additionally found that after operating for five to eight months, the average wind turbine will have offset the energy expended during its manufacturing.

The same study noted that "wind turbines produce energy with virtually no emissions." According to the Department of Energy's National Renewable Energy Laboratory, coal-powered electricity releases about 20 times more greenhouse gas per kilowatt-hour than wind.

More whataboutism and a non sequitur by comparing coal power generation to wind power when the topic at hand was construction. 

Quote

"You know what they don't tell you about windmills?" Trump told the crowd, "After 10 years, they look like hell. You know, they start to get tired, old. You got to replace them. A lot of times, people don't replace them. They need massive subsidy from the government in order to make it." 

Facts First: The government does not provide subsidies for wind turbine repair or replacement. Though wind farms receive a tax credit if they produce a certain amount of energy within their first decade, this subsidy will be phased out by 2020. Furthermore, the average lifespan of a wind turbine is 20-25 years, not 10. 

 

Property value

 

Trump claimed, "If you own a house within vision of some of these monsters, your house is worth 50% of the price."

Facts First: This is not the first time Trump has claimed proximity to a wind turbine impacts property values. However, several major academic studies found no statistically significant decrease in the average property value due to wind turbines in the US.

While some properties may see a decrease in value when turbines are constructed nearby, a 2016 studythat analyzed home sales within 10 miles of wind turbines and over 15 years in one state found "no unique impact on the rate of home sales near wind turbines." 

Ben Hoen, one of the authors of the study and a researcher at the Lawrence Berkeley National Laboratory, told CNN that the study also found a "majority of those living within a half a mile (from wind turbines) do not believe their property value has been inversely impacted."

Yes wind is subsidized. Are there wind farms no longer operating? Yes. Did they last 25 years? Not even close. 

The next point is even funnier. I can name certain high powered senators and congressmen from New England states who adamantly refused to allow wind farms offshore where they might see them. But yeah, I'm sure they weren't concerned with their property values. 

Gotta love those CNN "fact" checks

[Enthalpic + 1,496]

Super hydrophobic / ultra-low friction coatings could be used. 

[Douglas Buckland + 6,308]

58 minutes ago, Enthalpic said:

Super hydrophobic / ultra-low friction coatings could be used. 

Hmmm...bet hey hadn’t thought about that yet...😂

[footeab@yahoo.com + 2,187]

5 hours ago, Enthalpic said:

Super hydrophobic / ultra-low friction coatings could be used. 

Said coatings are VERY soft.  They get destroyed by particles(rain, dust, hail, snow) hitting at 200kmph or 300kmph very rapidly which creates massive amounts of drag. 

One funny solution was to use lasers which interact only at the frequency of ice.  On the face of it, it sounds pretty good.... uh, lots and lots of different compositions of ice... big no go, but even assuming you could accurately predict the water form on the blade, who is to say some did not get jammed into a crack somewhere and when said laser hits it, said crack literally "blows up" making it larger....

[NickW + 2,714]

16 hours ago, Ward Smith said:

Found CNN hatchet job and wanted to address it here

So, "facts first" can't address the argument, but like a lot of folks here, plays whataboutism instead. Plus I'd add the types cats kill are primarily little garbage birds that are non native and over populous. Not like cats kill eagles and owls who are attracted to the carnage from those cuisanarts of the sky. 

Then there's something about eagles and facts first  CNN wants us to ignore their last paragraph. It was also interesting to discover they get to kill 4200 eagles. 

More whataboutism and a non sequitur by comparing coal power generation to wind power when the topic at hand was construction. 

Yes wind is subsidized. Are there wind farms no longer operating? Yes. Did they last 25 years? Not even close. 

The next point is even funnier. I can name certain high powered senators and congressmen from New England states who adamantly refused to allow wind farms offshore where they might see them. But yeah, I'm sure they weren't concerned with their property values. 

Gotta love those CNN "fact" checks

In the US the tax production credit is being phased out as of 2020. Generally Onshore wind doesn't need any subsidy anymore. 

Turbines typically have a life of 25-35 years. I don't know about the US but in Europe smaller 1990's turbines get taken down and replaced with larger more efficient turbines as its easier to get planning consent for an existing site. The old turbines are then redeployed, often on Industrial parks where planning issues don't typically arise. My wifes firm have a 500KW mid nineties model on site which is estimated to have another 10-15 years working life. The investment is moderately profitable and is not subsidised in any form. The electricity produced simply offsets what would otherwise be imported. 

[footeab@yahoo.com + 2,187]

On 12/24/2019 at 10:05 AM, NickW said:

he investment is moderately profitable and is not subsidised in any form. The electricity produced simply offsets what would otherwise be imported. 

Yup: If you import energy it is like paying for it twice. So break even price is actually 2x domestic.  So, if you pay 15c/kWh, then 30 is break even.  Now if you produce enough already....

EDIT: No, the blades do not have a 25-->35 lifespan.  Tower?  Sure.  Blades main bearings?  No. 

Edited December 25, 2019 by footeab@yahoo.com

[Ward Smith + 6,615]

Interesting discussion on Quora concerning break-even analysis

[NickW + 2,714]

On 12/26/2019 at 6:50 AM, Ward Smith said:

Interesting discussion on Quora concerning break-even analysis

Interesting in at the time of reading in that the figures for the PTC are grossly exaggerated and the post contains no real detail just some random figures about how much coal and oil is required to produce a turbine with no reference to the actual turbines size. 

So the guys claim is that it takes 140 tonnes of coal to produce the steel (assumes its all coming from Iron Ore) for a turbine tower. He doesn't state the size so I will assume 1.5 MW which is a common GE sized unit over the last decade

Assume that unit has a capacity factor of 33% (can be ramped up and down to give different figures) it will produce 4.35 gwh per annum

How much coal does that displace in a conventional coal fired  power station?

Assume its bituminous coal with a calorific value of 30mj/KG

Power station has a conversion efficiency of 33%

1550 tonnes of coal per year. 

Ok - I know there are other energy inputs but this demonstrates that the energy payback is within the first year or possibly 2 (if assuming its a poorly sited turbine) 

 

 

 

[Ward Smith + 6,615]

15 hours ago, NickW said:

Interesting in at the time of reading in that the figures for the PTC are grossly exaggerated and the post contains no real detail just some random figures about how much coal and oil is required to produce a turbine with no reference to the actual turbines size. 

So the guys claim is that it takes 140 tonnes of coal to produce the steel (assumes its all coming from Iron Ore) for a turbine tower. He doesn't state the size so I will assume 1.5 MW which is a common GE sized unit over the last decade

Assume that unit has a capacity factor of 33% (can be ramped up and down to give different figures) it will produce 4.35 gwh per annum

How much coal does that displace in a conventional coal fired  power station?

Assume its bituminous coal with a calorific value of 30mj/KG

Power station has a conversion efficiency of 33%

1550 tonnes of coal per year. 

Ok - I know there are other energy inputs but this demonstrates that the energy payback is within the first year or possibly 2 (if assuming its a poorly sited turbine) 

You realize of course that unlike a wind turbine, the nameplate capacity of a coal plant ACTUALLY equals its output. A one gigawatt coal plant can easily produce 1GW day in, day out, 24 hours a day. Conversely, a 1.5 MW wind turbine might NEVER produce 1.5 MW, in its entire lifetime! Well, it might for 15 minutes of about one 24 hour period. I used to post a link directly into the Bonneville Power website, which had direct data of their windmill production figures. They had it on an hourly basis, and you could graph the output in watts. Unfortunately, I suppose I directed too many people there so they took it offline. The reason I sent folks there was because they never touched nameplate capacity. Real wind turbines, real world along an excellent wind corridor. 

[NickW + 2,714]

17 hours ago, Ward Smith said:

You realize of course that unlike a wind turbine, the nameplate capacity of a coal plant ACTUALLY equals its output (1). A one gigawatt coal plant can easily produce 1GW day in, day out, 24 hours a day (2). Conversely, a 1.5 MW wind turbine might NEVER produce 1.5 MW, in its entire lifetime! Well, it might for 15 minutes of about one 24 hour period. I used to post a link directly into the Bonneville Power website, which had direct data of their windmill production figures. They had it on an hourly basis, and you could graph the output in watts. Unfortunately, I suppose I directed too many people there so they took it offline. The reason I sent folks there was because they never touched nameplate capacity. Real wind turbines, real world along an excellent wind corridor. 

1. of course - thats why on the worked example I put a capacity factor of 33% (vary accordingly to the site in question). The annual electricity production is calculated based on a 33% capacity factor. 

2. One of the key points here to add is that while wind is free your 24/7 coal plant will burn a lot of coal that has to be paid for - something in the region of $75-80 a tonne for thermal bituminous coal.