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I wouldn't call it just hot air--wind energy is capable of serving some amount of our electricity needs, but what that amount is remains unclear. You see lots of articles like this talking about installed capacity, but I have yet to come across actual generation amounts (delivered MW-Hr).
One of the big drawbacks to wind energy for serving electric load needs is its inconsistency. Since as of yet there is no way to efficiently store electric energy on a large scale, electricity is delivered in the same instant it is generated. Since electric load is relatively constant (it doesn't change with wind speed), there has to be a generator running in parallel with the wind turbines to compensate for the changes in the wind turbines' output as the winds change--otherwise you'd have a brownout every time the wind dropped. The problem with this is boilers aren't cabable of changing their output as quickly as wind turbines, so there are a limited number of options for the parallel generator (hydro or natural gas turbines come to mind). And in the end, regardless of how much wind capacity is installed, there still has to be enough traditional generation installed to meet peak load, in case the wind isn't blowing during peak load times.
What I'm getting at is even though a lot of wind turbines are being built, it doesn't decrease the need for traditional fossil and nuke plants. And building both increases overall capital costs, and the cost of the end product.
I'm not saying that having wind power available isn't a good thing, and I'm not denying that the wind turbines will cause some offset of fossil-fuel burning, but I don't yet see it as an end-all to our energy problems. I think this and all inconsistent energy sources will only be auxiliary to the traditional sources until we come up with an efficient way to store enormous amounts of electrical energy cheaply.
One of the big drawbacks to wind energy for serving electric load needs is its inconsistency. Since as of yet there is no way to efficiently store electric energy on a large scale, electricity is delivered in the same instant it is generated. Since electric load is relatively constant (it doesn't change with wind speed), there has to be a generator running in parallel with the wind turbines to compensate for the changes in the wind turbines' output as the winds change--otherwise you'd have a brownout every time the wind dropped. The problem with this is boilers aren't cabable of changing their output as quickly as wind turbines, so there are a limited number of options for the parallel generator (hydro or natural gas turbines come to mind). And in the end, regardless of how much wind capacity is installed, there still has to be enough traditional generation installed to meet peak load, in case the wind isn't blowing during peak load times.
What I'm getting at is even though a lot of wind turbines are being built, it doesn't decrease the need for traditional fossil and nuke plants. And building both increases overall capital costs, and the cost of the end product.
I'm not saying that having wind power available isn't a good thing, and I'm not denying that the wind turbines will cause some offset of fossil-fuel burning, but I don't yet see it as an end-all to our energy problems. I think this and all inconsistent energy sources will only be auxiliary to the traditional sources until we come up with an efficient way to store enormous amounts of electrical energy cheaply.
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benbo
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Every area of the power/energy industry needs skilled workers. They are retiring at a rapid pace without replacement. I would sure look into it if I were just graduating.
What mudpuppy says is 100% correct. Even though I don't know a whole lot about it, I am on a NERC working group trying to come up with reliable availability data for wind generation. Other groups have attempted the same thing. THe problem with wind turbines is that they are effected by almost all the ambient conditions. Not only can they not generate if there is too little wind, they can't generate if there is too much wind. And they don't work as well when it is really hot, which is exactly the time when demand is greatest. THe problem they have been having is when utilities plan wind into their supply calculations they find that often the wind turbines underperform. It is really hard to predict. Nevertheless, they are becoming a valuable part of the mix. You have a lot of these wind turbines, many of which are qualified facilities, requiring that utilities purchase their power, or are part of required Renewable portfiloios. So they run along with other load following fossil plants, which make up for drops in capacity. I mean, the less fuel you burn, the less greenhouse gases, the less oil or gas we have to buy. I don't think it's a crisis, but it certainly can't hurt.
I think FPL is a pretty forward looking company. THey already have a huge amount of wind generation, some solar, and apparently (according to something I read here) are now attempted to license nukes. All along with plenty of fossil plants.
What mudpuppy says is 100% correct. Even though I don't know a whole lot about it, I am on a NERC working group trying to come up with reliable availability data for wind generation. Other groups have attempted the same thing. THe problem with wind turbines is that they are effected by almost all the ambient conditions. Not only can they not generate if there is too little wind, they can't generate if there is too much wind. And they don't work as well when it is really hot, which is exactly the time when demand is greatest. THe problem they have been having is when utilities plan wind into their supply calculations they find that often the wind turbines underperform. It is really hard to predict. Nevertheless, they are becoming a valuable part of the mix. You have a lot of these wind turbines, many of which are qualified facilities, requiring that utilities purchase their power, or are part of required Renewable portfiloios. So they run along with other load following fossil plants, which make up for drops in capacity. I mean, the less fuel you burn, the less greenhouse gases, the less oil or gas we have to buy. I don't think it's a crisis, but it certainly can't hurt.
I think FPL is a pretty forward looking company. THey already have a huge amount of wind generation, some solar, and apparently (according to something I read here) are now attempted to license nukes. All along with plenty of fossil plants.
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C-Dog
Well-known member
Oh, place them off the cost, where the wind does not stop. There is enough energy off the souther coast of Long Island to provide 4x the power that NY state currently uses.
I drove by a windfarm last weekend on the big island of Hawaii (Southern Most Point of the US) right on the coast which seems like a perfect place to hold such. It was an extremely windy day 20+ mph trade winds and of 24 turbines, 5 were in operation, the ones not operating seemed to be older models, maybe they are looking for experienced operators?????????? I just can't imagine how much of a requirement there is for trained operators, it seems to me they either spin or don't. We are doing a project for the airport which will place 13 small turbines on the roof to supply some of the power to the building the models proposed operate at 4 mph winds
G
Guest
My lead-in comment is tongue-in-cheek but I wanted to generate (no pun intended) a little discussion about the other alternative energy sources within the context of the one source that is poised to rule them all (nuclear). So far we are getting some good feedback! :thumbs:
It is a little more complicated than spin or no-spin. My understanding is that many of these wind farms are located traditionally within unhospitable regions where one doesn't exactly like to be out in the elements. Additionally, there is A LOT of manual labor in the form of climing up and down on these windmills - it is very physically demanding. I have heard for those reasons it is hard to keep an adequate supply of technicians and operators.
That sounds like a good idea - is there any increase in net energy loss by generating hydrogen gas rather than converting wind energy to electricity? Without knowing anything, I would think the hydrogen gas production would be MORE energy intensive and yield less 'usable' energy at the end of the process than generating electricity via a turbine. Again - that is just my first thought without knowing much else - I am open to more informed opinions!
ld-025:JR
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From what I understand, generating hydrogen gas takes more energy input than you get out of it, which is why wind or solar makes the most sense, IMO - if you aren't able to use all the energy when the wind is blowing, might as well store it in the form of a portable fuel that makes so much sense on so many other levels (emissions, safety, etc.). Maybe battery storage is the overall better deal, I am just not sure. But what I like about hyrdogen and fuel cells is the lower amount of hazardous waste generated as opposed to all those batteries to manufacture and then get rid of. I'd love to see some overall cradle-to-grave comparisons on energy efficiency, cost, and waste generation.
G
Guest
IMHO, I think that should be a REQUIRED part of the analysis - after all energy efficiency isn't the only measuring stick when it comes to being a good environmental steward.
It would be nice to see green 'offset' credits for such analysis - it would spur even more innovative approaches AND incentive for companies to subsidize alternative energy sources.:2cents:
JR
mizzoueng
Hop Addict
Wind farms right now are a good idea, but like mudpuppy said, the reliability of them are horrible. Currently most states are trying to pass legislation to force the utilities to become "more green".
Minnesota is an example. But 2015 all utilities in the state have to produce 15% of their net generation by "green" methods. This usually means renewable resources. By 2025, 25%.
I know a couple utilities looked into wind farms as they would be an easy write off, the reliability can be taken into account and the fact that they have the generation capacity there, they meet the criteria even if the farms are not producing 100% of the time.
Nukes are the future, but the distant one. Right now I think the power field needs to find fuels to replace coal and oil. Biomasses are very good ideas, but its hard to find fuels that have identical BTU ratings without using 100x the amount to reach it.
An example, I did a study on a wood boiler. we found that to replace a 8400 BTU Antelope PRB coal, it took the equivalent of 100,000 lb/day of trees to meet the generation demand. It would require a tree farm to use genetically enhanced trees to grow and mature in 1 year, the farm itself would be large. Once the client saw that it would take a farm the size of Manhattan to produce the trees required, i think it got scrapped.
this is why we cannot get away from coal right now, there just isn't a good replacement. We've thought about this, everything from liquified turkeys, to human remains to grain residue (rice hulls and grain dust).
If you can find a renewable resource that is as dense and has the heat capacity of coal, you will be a billionaire.
Minnesota is an example. But 2015 all utilities in the state have to produce 15% of their net generation by "green" methods. This usually means renewable resources. By 2025, 25%.
I know a couple utilities looked into wind farms as they would be an easy write off, the reliability can be taken into account and the fact that they have the generation capacity there, they meet the criteria even if the farms are not producing 100% of the time.
Nukes are the future, but the distant one. Right now I think the power field needs to find fuels to replace coal and oil. Biomasses are very good ideas, but its hard to find fuels that have identical BTU ratings without using 100x the amount to reach it.
An example, I did a study on a wood boiler. we found that to replace a 8400 BTU Antelope PRB coal, it took the equivalent of 100,000 lb/day of trees to meet the generation demand. It would require a tree farm to use genetically enhanced trees to grow and mature in 1 year, the farm itself would be large. Once the client saw that it would take a farm the size of Manhattan to produce the trees required, i think it got scrapped.
this is why we cannot get away from coal right now, there just isn't a good replacement. We've thought about this, everything from liquified turkeys, to human remains to grain residue (rice hulls and grain dust).
If you can find a renewable resource that is as dense and has the heat capacity of coal, you will be a billionaire.
Dark Knight
Silent Guardian
I am a Photovoltaic fan. We are trying to put in place an incentive program here but my ideas, well received at the beginning, are finding obstacles after obstacles right now. Since I am not a politician the battle is going South quickly.
C-Dog
Well-known member
Yes, but that is the amount of available energy offshore of LI. I tried to find the report from a SUNY that contained the #s... I will keep looking. But with 3.6 MW turbines you only need 9000 to generate that amount of juice.
Also, 144 MW are about to be installed: http://www.lipa.state.ny.us/cei/offshore.location.html
You need to crawl, before you can walk. You need to walk, before you can run...
C-Dog
Well-known member
Ok, more research has shown that LIPA has put the above mentioned wind farm back on the shelf.
http://www.ens-newswire.com/ens/aug2007/2007-08-27-097.asp
I saw another story saying it had been mothballed, but can't find it. I am internet challenged today.
http://www.ens-newswire.com/ens/aug2007/2007-08-27-097.asp
I saw another story saying it had been mothballed, but can't find it. I am internet challenged today.
Capt Worley PE
Run silent, run deep
I'm actually a fan of nuke, wind, and solar. I'd rank them in that order, too, for current viability. I think a lot more could be done with passive solar designs than we are doing right now; it'd be more effective than cells at tis juncture.
C-Dog
Well-known member
Here is some hot air for you...
http://www.calenergy.com/html/aboutus4c.as...high&tour=8
Actually it is hot earth and a virtual tour of how to extract energy from it.
http://www.calenergy.com/html/aboutus4c.as...high&tour=8
Actually it is hot earth and a virtual tour of how to extract energy from it.
Wolverine
Uncanny Pompadour
I'm loving this thread but have nothing much to add; it's all been too well-spoken already.
The difference between alternative energy and nuclear energy in practical application is 103.
The difference between alternative energy and nuclear energy in practical application is 103.
A case in point of what happens when the wind suddenly stops blowing, from http://news.yahoo.com/s/nm/20080228/us_nm/...ercot_wind_dc_1 :
HOUSTON (Reuters) - A drop in wind generation late on Tuesday, coupled with colder weather, triggered an electric emergency that caused the Texas grid operator to cut service to some large customers, the grid agency said on Wednesday.
Electric Reliability Council of Texas (ERCOT) said a decline in wind energy production in west Texas occurred at the same time evening electric demand was building as colder temperatures moved into the state.
The grid operator went directly to the second stage of an emergency plan at 6:41 PM CST (0041 GMT), ERCOT said in a statement.
System operators curtailed power to interruptible customers to shave 1,100 megawatts of demand within 10 minutes, ERCOT said. Interruptible customers are generally large industrial customers who are paid to reduce power use when emergencies occur.
No other customers lost power during the emergency, ERCOT said. Interruptible customers were restored in about 90 minutes and the emergency was over in three hours.
ERCOT said the grid's frequency dropped suddenly when wind production fell from more than 1,700 megawatts, before the event, to 300 MW when the emergency was declared.
In addition, ERCOT said multiple power suppliers fell below the amount of power they were scheduled to produce on Tuesday. That, coupled with the loss of wind generated in West Texas, created problems moving power to the west from North Texas.
ERCOT declares a stage 1 emergency when power reserves fall below 2,300 MW. A stage 2 emergency is called when reserves fall below 1,750 MW.
At the time of the emergency, ERCOT demand increased from 31,200 MW to a peak of 35,612 MW, about half the total generating capacity in the region, according to the agency's Web site.
Texas produces the most wind power of any state and the number of wind farms is expected to increase dramatically as new transmission lines are built to transfer power from the western half of the state to more populated areas in the north.
Earlier on Tuesday, grid problems led to a blackout in Florida that cut power to about 1 million electric customers across that state for as much as four hours.
