Why do wind turbines have such low durability compared to hydraulic turbines?

[etudiant]

It is a puzzle to see so many of the wind turbines that are idle.
Even in active wind farms, such as at Altamount Pass, it is usual to see at least 20% of the turbines idle. Older installations are usually idle as well.
Why is this?
Hydraulic turbines routinely run flawlessly for decades with very little downtime. Is it not surprising that wind turbines appear incapable of matching this?
It does seem a huge economic burden to idle these units. These are expensive structures, stuffed with precision mechanisms.

 

[jim hardy]

Why is this?

two reasons come to mind.

1. Wind power sells for a premium. If the utility can make it cheaper with coal than the windfarm sells it to them, that's what they will do. Unless gov't is forcing them to buy it.

2. A single steam plant might have the electrical output of 500 to 1000 windmills.
So you just can't afford the same level of staffing for a windmill.

A one megawatt windmill makes electricity enough to sell for perhaps fifty or a hundred dollars an hour. It can't suppport the interest payments on loans to build it AND a big maintenance staff. If one is offline it's not a lot of revenue lost.
Probably they wait until there's enough "Fix Me's" to justify calling out the service crew.

The Altamont wind farm consists of about 4,800 small wind turbines with a capacity of 576 megawatts

Wow those ARE tiny , only 0.12 megawatts apiece. The whole windfarm amounts to half a big steam plant.

 

[mheslep]

It is a puzzle to see so many of the wind turbines that are idle.
Even in active wind farms, such as at Altamount Pass, it is usual to see at least 20% of the turbines idle. Older installations are usually idle as well.
Why is this? ...

Altamount is one of the oldest (major) wind farms in the US. If it uses 1990's wind turbine tech it may not be illustrative of the reliability of turbines built today.

 

[etudiant]

Altamount is one of the oldest (major) wind farms in the US. If it uses 1990's wind turbine tech it may not be illustrative of the reliability of turbines built today.

Absolutely true, Altamount was one of the first sites used because it is also one of the best sites available. So it will have old turbines, but that still leaves the question of why so many of them are not replaced, but left idle when the wind continues to blow . I'd have thought that there would be a push to use the resource, not to waste it.
Yet that phenomenon, lots of idle turbines, is apparent wherever wind farms are found.
I've seen it in several places in Europe as well.
Can anyone from industry help explain what is going on?

 

[AlephZero]

Companies don't build wind farms to make electricity. They build them to make money.

If you get a huge governmemt subsidy for building a new wind farm, and peanuts from the electricty it generates, it's not your problem that the system is "stupid". You just build it and take the money.

 

[jim hardy]

I'd have thought that there would be a push to use the resource, not to waste it.

the resource is tax credits.
It's largely foreign banks financing US windfarms and transmission lines, as well as lots of other infrastructure. It draws foreign money into US which i guess makes government happy.

Put on your accountant's hat - when the balance sheet no longer justifies running the darn thing because there's no production tax writeoff, you abandon it.
This page says the tax credit generally goes ten years
http://dsireusa.org/incentives/incentive.cfm?Incentive_Code=US13F

An older Nuke plant that's no longer paying interest on the loan to build it can make electricity for about what the windpower production tax credit amounts to.
A utility that's run by accountants might do better buying an old Nuke than a windfarm.
That's why gov't is mandating certain % electric generation be renewables, it creates a market for them.

You need to read C Northcote Parkinson's 'Law of Delay' to become properly cynical about the oxymoron '(insert corporate or government) wisdom'.

 

[jim hardy]

Please don't take me for anti- green.

What we as good citizens should do is reduce our use where we can.

A flat plate solar water heater will work in most of the US and heating water is a big chunk of your electric bill.

Somebody neeeds to make a solar airconditioner for the sunbelt, perhaps a sealed ammonia or steam system that runs in batch mode sized for the 12 hours of sunlight.

 

[mheslep]

Companies don't build wind farms to make electricity. They build them to make money.

If you get a huge governmemt subsidy for building a new wind farm, and peanuts from the electricty it generates, it's not your problem that the system is "stupid". You just build it and take the money.

In the US the two, wind power generation and the subsidy are connected, hence the name "Production Tax Credit". The operator is given a subsidy per kWh generated. No power, no subsidy.

 

[mheslep]

the resource is tax credits.
It's largely foreign banks financing US windfarms and transmission lines, as well as lots of other infrastructure.

Do you have a source handy for that claim on "largely" "foreign" finance or wind turbines?

It draws foreign money into US which i guess makes government happy.

Put on your accountant's hat - when the balance sheet no longer justifies running the darn thing because there's no production tax writeoff, you abandon it.
This page says the tax credit generally goes ten years
http://dsireusa.org/incentives/incentive.cfm?Incentive_Code=US13F

Sure, though the relevant question with wind turbines or any other enterprise is what's on the balance sheet. Is it the case that these old 1990's turbines break as fast as they can be fixed, or is any maintenance on any tower (new or old) cost prohibitive?

An older Nuke plant that's no longer paying interest on the loan to build it can make electricity for about what the windpower production tax credit amounts to.

Even with zero PTC the wholesale price of electricity in California is 3-4 cents/kWh, and these wind turbines don't need a large staff of well paid security guards and operators, nor refueling every three years. So the question is can a wind turbine be maintained annually when it makes 3-4 cents/kWh at 30% capacity factor.

 

[mheslep]

Another relevant point: the US spills (ie throws away) 1-3% of its total wind generation because the operators occasionally find themselves in a situation where they have surplus power, but the load point and predictability are such that they can not gamble on idling a fossil plant to use the wind generation and then have the wind die. I have no idea if this explains the observation of many idle wind turbines reported above. It would not surprise me to find that, when operators are forced to idle turbines during a surplus, they concentrate the shut downs in areas of high maintenance cost, i.e. the oldest turbines.

Wind Curtailments.
The above suggesting that some wind farms are built knowing that on day one of operation there is insufficient transmission to deliver peak output of the wind farm should it occur.

 

[jim hardy]

Do you have a source handy for that claim on "largely" "foreign" finance or wind turbines?

not all in one place.
The way i got into it was this

a friend is developing a windfarm and has courted several investors.
When i tracked them they were all backed by European banks, largely Spanish , some Italian one French.
Tracking the other investments on the bank's sites i found they are building toll roads, transmission lines, dams here...

One almost has to go company by company.
You'll notice GE is the only US manufacturer of wind turbines.
Look at Vestas, Nordex, Alstrom, Siemens, and see who's financing the farms using their turbines.


http://www.renewableenergyworld.com/rea/news/article/2012/05/foreign-dominance-of-us-clean-energy-market-spells-trouble-for-america

Further, foreign countries are investing here in the U.S. Of the 26 banks that were actively investing in clean energy in America in 2010, only six of them were U.S. based. However, what concerns Third Way the most is not that foreign countries are increasingly investing in clean energy, both in their own countries and in America; in fact, this is seen as a vote of confidence for the U.S. market, not to mention the whole industry. What is worrisome is that it appears as though the outsiders are seeing a gold mine in the U.S. clean energy economy while the American Congress sits idly by doing nothing, says Third Way.

http://www.sustainablebusinessoregon.com/articles/2010/09/iberdrola_plans_6b_investment_by_2013.html

Iberdrola Renewables, the U.S. division of Spain-based Iberdrola Renovables SA, made waves at an energy conference this week by announcing plans to invest $6 billion in energy generation by 2013.

Frank Burkhartsmeyer, vice president of strategic planning for Portland-based Iberdrola U.S., spoke on a panel about large energy projects at the World Energy Congress in Montreal Wednesday and outlined his company's plans to add 3,000 megawatts of power capacity over the next three years. His comments attracted the attention of Bloomberg News.

"Demand is growing but there are three factors that influence supply as we see it: the quality of the wind source, predictable, supportive renewable energy policy, and the ability to get power to customers," Burkhartsmeyer said, according to Bloomberg.

Bolstered by the stimulus package, Iberdrola is on track to reach the $6 billion investment goal, according to Iberdrola spokeswoman Jan Johnson.

Iberdrola is the second-largest wind power operator in the United States with an installed capacity of 3,877 megawatts produced at 41 wind farms in 23 states.

http://issuu.com/thirdway/docs/third_way_report_-_fire_sale_the_end_of_american_o/1#download
this is all i could get, it's behind a subscribe-wall..

With Congress seeming to have abandoned the clean energy sector, American companies are fighting for capital, and survival. Others are moving in. Third Way has found that this capital hole is beginning to be filled by funds from outside the United States. Chinese investment in the U.S. market jumped 130% in 2011 and the French took control of the second-largest U.S. solar panel maker. Foreign investment in American clean energy is a great sign for the sector, jobs, and tax revenues. We support it. But we do not want the U.S to lose entirely our leadership in the clean energy sector and see domestic companies competing in a $2.3 trillion global market disappear.

http://www.dallasnews.com/news/washington/20091117-Dallas-investor-Chinese-partners-propose-1032.ece

WASHINGTON - Dallas investor Cappy McGarr said Tuesday that his Chinese partners in a $1.5 billion West Texas wind energy farm proposed last month have agreed to build a turbine manufacturing plant in the United States.

then try to figure out just who owns whom..

http://www.terra-genpower.com/News/Allco-Finance-Group-(AFG)-Announces-the-Sale-of-th.aspx

Allco Finance Group (AFG) Announces the Sale of the Tehachapi, US Wind Development Project

6/17/2008
ASX-listed Allco Finance Group ("Allco") and a consortium comprising the US-based ArcLight Capital Partners and Terra-Gen Power, have today agreed to the sale and purchase of Allco's and its co-investors' US wind energy interests for a total sale price of US$325 million. The interests being sold comprise a circa 3100MW wind development project in Tehachapi, California, one of the largest wind development projects in the world.



Allco and its co-investment partners will realize significant liquidity and profitability from the sale which is part of a previously announced Allco asset sales program.


Nick Bain, Allco's Head of Infrastructure, said, "This sale has delivered to Allco and its co-investment partners a highly profitable outcome in a relatively short time frame, a result of Allco's decision 2 years ago to establish its global wind energy business."



Steen Stavnsbo, Allco's Head of Wind Energy, added "In Tehachapi, we have benefited greatly from our relationship with our development partner, Oak Creek Energy Systems, a subsidiary of Japanese Marubeni Corporation, who has played a pivotal role in the development of the project to date".

Allco seems to be Australian.
Terragen I'm not sure, but they seem entwined with these guys:
http://global-infra.com/ , click on their investments..
http://www.terra-genpower.com/Home.aspx

i think we've achieved globalization.

I'm glad I'm a theta.

old jim

 

[AlephZero]

In the US the two, wind power generation and the subsidy are connected, hence the name "Production Tax Credit". The operator is given a subsidy per kWh generated. No power, no subsidy.

Well, let's not go off topic to the question "if wind power is economically viable, why does the wind industry even need subsidiies"...

But back to the OP's question, another issue is distributing the power form the wind farm to the consumers. That had led to silly situations in Scotlamd for eaxmple, which has good sites for onshore wind farms but low local demands for power. That has led to wind farms being built (and subsidised) that can not be run at full power because the distribution network doesn't have enough capcaity to handle the power being generated, and the distribution companes (which are separate from the generation companies, and don't have the same access to "green energy" subsidies) can't afford to fix the problem using their own finances.

 

[mheslep]

Well, let's not go off topic to the question "if wind power is economically viable, why does the wind industry even need subsidiies"...

But back to the OP's question, another issue is distributing the power form the wind farm to the consumers. That had led to silly situations in Scotlamd for eaxmple, which has good sites for onshore wind farms but low local demands for power. That has led to wind farms being built (and subsidised) that can not be run at full power because the distribution network doesn't have enough capcaity to handle the power being generated, and the distribution companes (which are separate from the generation companies, and don't have the same access to "green energy" subsidies) can't afford to fix the problem using their own finances.

Yes insufficient transmission is a plausible explanation for the reports of idle wind turbines, though I have no specifics from operators showing this to be the case. Doesn't address whether or not the wind farm is economic; it may still be.