# Wind Energy

Recently when driving in Western Illinois near the Iowa border I noticed a vast field of wind turbines off Route 20. On the way back to Chicago I got off the highway and started driving on the rural dirt roads to get a closer look.

These are the wind turbines near Lena, IL. The turbines are part of the “EcoGrove” project. A firm called EcoEnergy was the project manager for this effort, and here is the web site describing the project. The project has a capacity of 100 MW and the turbines are between 1.5 and 2.5MW each… so there are at least 40-50 wind turbines at the site. The project cost \$200M (per the web site). Per the wind FAQ’s section of their site:

How big is a wind turbine?
EcoEnergy’s turbines typically measure 262 feet (80 meters) to the hub height (where the blades meet) and rotor diameters in the range of 246 to 295 feet (75 to 90 meters)..

As you can see from the photos, these wind turbines are huge. They were all turning slowly the day I was there in the wind, with three blades.

Because they don’t produce all the time, aren’t wind turbines an inefficient way to get our electricity?
Wind turbines actually generate electricity most of the time (65 to 80 percent), though the output amount is variable.

This is a strange question. You are wondering what the total output of wind energy is, and this just answers whether or not the turbine is generating any energy at all.

Wind turbines are actually extremely efficient. One of the simplest ways to measure overall efficiency is to look at the energy payback of an energy technology, or the amount of energy consumed in producing additional energy. The energy payback time for wind is similar to or better than that of conventional power plants. A recent University of Wisconsin – Madison study calculated that the average energy payback of Midwestern wind farms is between 17 and 39 times as much energy as they consume (depending upon average wind speeds at the site). Nuclear power plants generate only about 16 times as much energy as they consume and coal plants generate just 11 times as much energy as they consume.

This is another strange question and answer. I guess it makes sense that a wind turbine creates a high multiple of the energy that it consumes, because the marginal cost of fuel (wind) is zero. The issue is that this power is variable in time (possibly off-peak) and in quantity.

In general, wind energy in Illinois makes sense because most of Illinois is damn ugly. It is flat with cornfields and not much to look at. Actually the area near Lena, IL where these turbines are located is probably one of the prettiest parts of Illinois (admittedly, not saying much). But I don’t necessarily think that the wind farm is bad on the horizon, it is actually pretty cool. I don’t think that the wind farms significantly impact the farm economy; they take up some amount of land but not a lot of total acreage.

The issue too is cost efficiency. \$200M was spent for 100 MW of capacity, and this “capacity” is when the wind is blowing at a consistent rate best for the turbines. I don’t know what the practical capacity of a wind farm is, it obviously depends on specific circumstances, such as how windy it is. We also would need to understand the useful lives of the gear; they had some trouble with blades made in India but likely they have this figured out in the most recent wind farms.

At least in Illinois we have a decent transmission corridor and it is located near some urban areas in Iowa. We probably will be seeing more of these wind farms in the future.
Cross posted at LITGM

### 25 thoughts on “Wind Energy”

1. The math on a lot of alternative energy sources just doesn’t add up. Total electric power production in the US is around 1 Terawatt, to meet that demand with the windmills mentioned above we’d need well upward of one and a half million turbines of the above kind taking into account the average capacity factor for wind power (0.3, the same as achieved by this project). All of this would cost roughly \$7 trillion to deploy.

Extrapolating from large scale photovoltaic power plant projects (such as the Topaz solar farm) it would cost \$8 trillion (and an area the size of Washington state) to replace our entire electric power generation with solar power.

Even then, without massive, and expensive, changes to the power grid both wind and solar power generation would result in massive, routine black outs and brown outs.

Both solar and wind power are obviously not a workable solution for base power generation in the US, not at current costs and levels of technology.

2. From the FAQs: “No power plant – fossil fuel, nuclear or wind – generates energy at 100 percent “nameplate capacity” 100 percent of the time.”

This is true–usually no need to run the plant at full output at 3AM; however, a fossil or nuclear plant can generate energy at 100% **at the time it is needed**. This is far from true of a wind plant.

3. Nuclear plants take several minutes (around 30) to regulate their power output. This lag is being compensated by gas or water turbines right now. On demand power is no requirement for large scale power plants. Another concept that is being discussed is to buffer the output of wind turbines by means of compressed air (stored underground in depleted oil/ gas fields). Each turbine works on a compressor and the electrical power is then generated by a gas turbine working on the compressed air (and a small amount of fuel). Since gas turbines can be regulated pretty quickly, this would make a power plant that provides reliable constant output while at the same time being able to cover peaks in demand.
But even without buffering wind power has some good points for it: The real power of wind power is not that it’s green but the fact that the low investment volume of Wind turbines puts power generation back into the hands of entrepreneurs. Where I’m from (Northern Germany) communities start to install municipal wind parks to provide themselves with power while reclaiming the market for their people. The low maintenance/ fuel costs compared to other small scale power plants make wind power an extremely calculable investment. Another aspect to consider: The fuel can not be withheld by a foreign country. And the fact that the turbines of a wind park are spread over a large area makes it hard for terrorists to take a whole plant down with a single strike.
One last thing: In my hometown they just set up two 5 MW turbines. These things are really awesome to look at.

4. Any steam plant (nuclear/coal/gas) will take several minutes or even hours more for a large increase in output, but loading patterns over the course of the day follow a generally predictable curve and power output can be planned to follow it. Again, this is not true of wind.

C Trapp..can you tell us the current subsidy for wind power in Germany? I’m pretty sure it’s substantial, but don’t remember the exact numbers.

5. Are there any power generating windmill farms that are not government owned or government subsidized?

6. C. Trapp,

Nuclear plants take several minutes (around 30) to regulate their power output.

Yes, but (1) at least nuclear power plants can increase their output at will. Wind and other weather based power sources cannot. If power needs go goes up suddenly, the nuclear plant just needs to turn up a dial to eventually compensate. Weather based power is almost always maxed out i.e. it is producing as much power at any given time as weather will allow. (2) Any technique that can be used to buffer weather-dependent power can be used even more efficiently to buffer the output of nuclear power plants.

I would also note that you are comparing hypothetical future technology that will give a boost to weather-dependent power but comparing that fantasy technology to real-world actually working nuclear power. How does weather-dependent power stack up against hypothetical future nuclear technology?

The low maintenance/ fuel costs compared to other small scale power plants make wind power an extremely calculable investment.

Obviously not. Otherwise, there would be no need for massive subsidies of weather-power. Weather-dependent power doesn’t save anyone money because it can never replace the capital investment needed in conventional sources to take up the slack when the weather turns bad. At best, it saves some fuel cost but the capital cost can easily offset that.

7. C. Trapp wrote:

The low maintenance/ fuel costs compared to other small scale power plants make wind power an extremely calculable investment.

Shannon Love wrote:

Obviously not. Otherwise, there would be no need for massive subsidies of weather-power.

The word C. Trapp used was calculable, not profitable and he/she/disembodied-brain-in-a-jar is absolutely correct about that. The output, over time, of a given wind power installation in a given site is very calculable, based on the wind patterns for that site.

The fact that EcoEnergy studiously avoids quoting those oh-so-calculable numbers suggest that they know we won’t like them. Instead they quote obviously irrelevant statistics like overall up-time and energy payback. Guess what, potato batteries have much better up-time and energy payback than wind farms. Maybe we should cover the Midwest with them instead?

8. Did some research:

Capacity factors for wind farms in the US generally run in the range of 25% to 40%, with the highest values, not surprisingly, coming from Oklahoma and Nebraska. I found record of another wind farm in Illinois that has a capacity factory of about 25%.

These numbers are actually better than I would have expected. I’d be very interested to learn where in this range EcoEnergy expects their new site to perform. To bad they didn’t have the guts and honesty to publish those numbers along with their pseudo-data.

For comparison, total capacity factor for US nuclear plant was calculated at 92% in 2002. I didn’t find any more recent numbers than that.

9. Hey Jay, great photos. Now someone else is a better photographer than me.

As far as Germany, I find it HILARIOUS that the Germans would worry for one second about their fuel or money being withheld by a foreign country, since a huge percentage of their natural gas comes from a pipeline that the Russians usually hold hostage every year. They could have built more coal or nuclear plants to not be so dependent upon Russia but instead they use the quick n’ easy natural gas and a smattering of feel-good wind power and then wonder every year why they are dependent upon the most mercurial and dangerous large scale de-facto dictatorship in the world.

I’m not for or against wind, if it makes sense. Probably doesn’t make too much sense in Illinois given our likely low capacity factor. It could make a lot of sense elsewhere, or at least a bit of sense.

10. I remember when Lady Bird Johnson led the attack to tear down billboards to beautify America. Now the liberals are covering up that lovely landscape with thousands of windmills. I drive from Pittsburgh to San Francisco once a month (its faster than flying and much more pleasant) and I think these windmills uglify our country.

Can we get the billboards back to cover up the windmills? BTW billboards are good for small business and good for economic growth.

11. If you ever fly out of Denver to Chicago, you will very likely fly near one of the largest wind turbine areas in the country. The turbines, as noted are huge, and the Colorado turbines run from near Julesberg, Colorado to near Fort Collins. Each turbine has a large red light on the top, and at night you can see the vast expanse of turbines. Quite an amazing sight.

For the real advocates of wind energy, here is the shocker. They are absolute maintenance nightmares. Because of the variation in the wind, there is correspondingly variation in the turbine gearbox and the drive shaft that turns the generator. Electric generation operates best when the turbine shaft can turn at a relatively constant speed. The wind turbines don’t rotate at a constant speed and the slowdown, speedup, slowdown, speedup chews up the gears. If you want a great investment, invest in the companies that maintain these behemoths.

Oh, and one note for the environmental wackos – all those turbines in Colorado: They are chewing up golden eagles like crazy. Thousands of golden eagles have been killed because they located these turbines in the area called Grasslands National Park which is thousands of acres of native grassland on the Colorado-Nebraska border. Grasslands National is the prime hunting and nesting area for the golden eagle.

12. They are absolute maintenance nightmares.

I always guessed that they would be but was never able to track down maintenance costs. Do you have any figures?

13. Germans concerned about about independence from foreign energy markets sadly are in the opposition right now. The idea of liberating one’s economy from energy imports has been much more consequently been embraced by scandinavian countries. Right now they rely mostly on oil and gas but have taken into account that the supplies are limited. With now other resources at hand, renewables are the logical choice (this may be the reason why Denmark is the technological leader when it comes to wind power). When it comes to the ecological impact, one has to keep the effects of mining and drilling for fossil or nuclear fuels in mind. Wind mills may look ugly and damage habitats but the impact is far less than the one of strip mining for example.
On the sci- fi in pressurized air as buffer: They do it since 1870 (http://en.wikipedia.org/wiki/Compressed-air_energy_storage). Over here the first modern plant has been put to work in 1978 to buffer a nearby nuclear plant. They are proven technology to cover peak demand in areas that lack the mountains to build pump storage hydro power plants.

Btw, a good source for numbers is http://www.nrel.gov.

14. On maintenance costs: I just looked into the book by Robert Gasch and found some numbers on small scale mills (<500 kW): repair and maintenance begin at 15 \$ per [kW a] in the first year and rise to around 37 \$ after 12 years (Actually the data contains an outlier with 45 \$ at year 12 but year 11 and 13 are around 30 \$).

15. C. Trapp,

When it comes to the ecological impact, one has to keep the effects of mining and drilling for fossil or nuclear fuels in mind.

When it comes to windpower one must keep in mind the ecological impact of mining for construction materials, the building of roads and other infrastructure to support a massively spread out power scavenging system as well as the constant need to constantly replace parts owing the relatively high wear on weather-dependent equipment and the fact that such equipment has relatively short operational lifespans. You also have to take in to account that weather-dependent power is much more expensive and thus that it raises the cost of adopting new ecologically friendly technologies.

(Actually the data contains an outlier with 45 \$ at year 12 but year 11 and 13 are around 30 \$)

That outlier is almost certainly the result of weather damage and thus not really an outlier at all but a predictable cost surge in any system exposed to the weather for a long enough time. For example, if we put wind farms on or off the eastern coast of the US it is a dead certainty that over a 20 year operational life every single turbine will be stuck by at least one hurricane or devastating north easterner. It’s like calculating the cost of maintenance of a house in a flood plain. You get long stretches with no unusual cost but you know for certain that eventually the house will suffer major damage.

16. I think what will really happen is that U.S. utilities will purchase a lot of environmental holy water, in the form of solar/wind…but a high % of this capacity will be backed up by the purchase of natural-gas-fired capacity. This is *great* if you’re running (for example) GE Energy: you are in effect getting to sell the same capacity more than once, kind of like the real estate agent in the Ozarks where the land was so steep he could see both sides of the same acre. Not so great, though, if you’re paying electric bills.

17. One intersting marketing ploy that my local utility MG and E is using is that you can “opt” to pay up and do the “right thing” and buy a certain percentage of your power as wind power. Of course there is no way that the utility can regulate which power comes to your house, it is all the same by then.

18. Also, I always wonder how these things handle the snow/ice load and frigid cold in winter here in the upper Midwest. It must take its toll on the equipment.

19. One should look at cost figures with care. They are changing rapidly. Solar has achieved cost parity with coal in 2009 (no subsidy) and looks to get cheaper than cool soon. This is only for regions with very high amounts of yearly sunlight, of course, yet even this was supposed to be over a decade away a few short years ago.

Alternative energy systems stop being an alternative and start being the next big thing when they are the cheapest available solution. We’re rapidly getting there. But even when we get there, the problem that these newly economic forms of energy do not operate 24×7 but depend on environmental conditions remains a problem, one we don’t have a solution for, yet.

When we do get that solution, which I predict will be prior to 2020, I expect that we are going to witness a real switchover. The actual greens will be happy while the luddites will find all sorts of new excuses why these formerly championed power sources are no longer ok.

20. TM Lutas,

Solar has achieved cost parity with coal in 2009 (no subsidy) and looks to get cheaper than cool soon.

It might have passed so meaningless cost per kilowatt threshold but a solar power based power system is still fantastically more expensive than coal. A system is what you need to provide power 24/7. A system powers critical facilities and functions. Solar power cannot do that. All calculations about the cost of solar power has to include the cost of the fossil fuel/nuclear sources that take up the slack with the solar power isn’t there.

If weather-dependent power was viable as a primary source of power, we should expect to see a lot of little communities or facilities running completely off weather-dependent power. That is how all previous real energy sources began. They provided power for some critical or out of the way that justified the expense and inconvenience of the new technology. Then they take over more and more from the old power source because they are less expensive and more reliable. Weather-dependent sources by contrast cannot provide power for anything larger than a flashlight and can only function with a complete non-weather dependent backup. That alone should tell us they are non-viable.

21. Wind generators actually consume grid power when there is no wind. One reason is they have to periodically rotate the blades to keep the shaft from warping. None of the power they have taken from the grid is considered when accounting for production.
http://www.aweo.org/windconsumption.html

Wind power production is quite often very low during peak power consumption time periods.

Here is a link to some Bonneville Power Administration wind data and graphs. The top link on the page is a five minute real-time graph.

22. “One interesting marketing ploy that my local utility MG and E is using is that you can “opt” to pay up and do the “right thing” and buy a certain percentage of your power as wind power. Of course there is no way that the utility can regulate which power comes to your house, it is all the same by then.”

I don’t have a problem with what the utility calls “retail wheeling.” Say they generate 90 percent of their power with “dirty coal” and 10 percent of their power with “clean wind.” Suppose 10 percent of their customers pay they extra tribute money MG&E is asking for wind power. Even though the electrons get mixed together over the same wires, I have no concern for the 10 percent festooning their cars with goofy bumper stickers saying how morally superior they are for using “clean wind power” and for the remaining 90 percent being aloof to their use of electricity from clubbed baby seal carcasses.

The problem I have is saying that one is “getting 100 percent of their power from clean, renewable sources.” Tim Metcalf, I am talking to you.

You see, if Metcalf’s Sentry Hilldale was really getting 100 percent of their power from wind, does that mean that they turn of their refrigerated food cases and back-room storage areas on an off as the weather changes? Or do they provide their own backup — they could, you know, if they were really earnest about it, perhaps making ice or dry ice during the time the wind blows and then running their equipment off the stored ice when the wind is calm. Do they do that? I don’t think so. They fall back upon on the electric power grid to run their freezers the 75 percent of the time the wind is not blowing.

What I am saying is that this is a free-market economics Web site, isn’t it? I think all of us could buy into the argument that 10 percent of customers are really getting their power from wind, that is if 80 percent of customers could decide to “subscribe” to the wind power program and if MG&E honestly got 80 percent of its power from wind, but they can’t do that now, can they, because the wind is not steady enough.

Again what I am saying, the 10 percent who are claiming to get “100 percent wind power” are free riders on the remaining 90 percent of generating capacity from “dirty” sources. So Mr. Metcalf, do you just let all the food in your freezers spoil when the wind doesn’t blow?

23. For those interested in numbers, Vattenfall, the European energy group, publishes data on wind energy in their transmission area.

For an overview, look here.

http://www.vattenfall.de/cps/rde/xchg/trm_de/hs.xsl/151.htm

Interesting that, of the 9340 mW wind capacity installed today Vattenfall credits only 460 mW as dependable power. (See the referenced page for much more information.

The fully geeky can download excel spreadsheets with 15-minute wind infeed mW recorded since June of 2003:

http://www.vattenfall.de/cps/rde/xchg/trm_de/hs.xsl/150.htm

There are many numbers to crunch here for anyone interested in quantitative analysis of the behavior of a large wind system.

Pointers to wind data from the other German grid operators are here: