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Wind Turbines 2

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I had a call from Sustainable Scotland this week touting the next conference and claiming of wind farms that the evironmental issues were all positive as even the RSPB "were calling for them". There followed an unsatisfactory dialogue about raptors and bats... and a suspicion that the RSPB position was being misrepresented a bit.
Are the greens all now in favour? Perhaps not as this article suggests:
Note who the author is and check out his green credentials....

JMW
 
I read it as the Greens are willing to cooperate, if the batbeaters are willing to leave the reserve areas alone, as well they probably should anyway. That dosn't sound like total capitulation. More like a plea for reason and some form of coexistance.

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"Pumping accounts for 20% of the world’s energy used by electric motors and 25-50% of the total electrical energy usage in certain industrial facilities."-DOE statistic (Note: Make that 99% for pipeline companies)
 
An interesting article in the Guardian (It says that climate change (contrary to the understanding fostered/promoted by Al Gore in his comments on tornadoes etc.) is responsible for significant drop in winds.

Of course, the article hasn't been published yet, it has been, as is commonly the case these days, "leaked" to the press prior to publication in the "peer reviewed Journal of Geophysical Research" which one supposes is meant to imply that it is peer reviewed when it actually makes no such claims; indeed, the article may yet fail to be published.

In any event, they seem to be laying the groundwork for the excuses that will be trotted out when everyone discovers that wind farms don't generate nearly as much energy as promised.... its all due to AGW of course.

JMW
 
I saw the same information presented as fact on TV news. One thing that was notable about this segment was that the co-anchor asked a DB question, "What happens when there is no wind?". The answer was you get electricity off the grid.

The local GE Wind Turbine Plant is calling back workers and shipping components 2 x 2 x 2....
 
you get electricity off the grid??

So who puts it on the grid??

Can I become a journlest and ask DB questions??

Does anyone care if the power on the grid goes off??

That's the reason science classes are required in college.
Can you tell how miffed these people make me??
 
JMW,
AGW?

Uncle Syd,
DB question?

Cranky,
The grid includes many Mega boiler steam turbine generators (assorted fuels) and gas turbine driven peaking units. If wind accounted a far greater percentage of the power then it could be a problem. However, presently the grid can accomodate diverse renewables with some solar, some wind, etc. The loads are variable too.

One could rationally advocate both nuclear mega generators and renewables; and perhaps oppose new coal burning plants. Such advocacy is lame without selecting a renewable based electrical utility company. This sort of ties back to the irony mentioned in the original post, "... components are made by GE in a building built for Westinghouse Nuclear Components Division". Sure, coal will return when we use up all the uranium, wind and sunshine. ;-)
 
The Co-Anchors were a male and female (blond) and the male gave the information in "technical way" and after his spiel the female asked the question "What happens when there is no wind?" to which he gave her the look of why would you ask such a dumb (blond) question. His answer was that when this happens you get electricity off the national electric grid. Her question was related to information presented that there was going to be a fair reduction in available winds based on the 1973 survey.
 
In many locations there is a low voltage ride through requirment for power producers including wind.
Why do you think that is?

It seems that someplace doring a fault there was a loss of several hundred megawatts of power production.
What happens when you loose several hundred megawatts on the grid? The frequency can drop, and automatic load shedding goes into effect, or another stability problems comes about.

Solution: require spinning reserve of firm power from all power producers.

Problem #2: because of heat generation sources nucular and coal generation has a limited ramp rate.

Soultion2: use gas turbins to follow the wind.
How ironic that we have to follow the green power with the most expencive energy source.
 
Well, it needn't be gas turbines.
I am told by a Dutch friend (I haven't checked)that the Dutch are constructing a new bolder (dyke) so that they can use surplus wind energy to fill it and when the wind drops they can use the outflow to drive turbines...

JMW
 
True pumped hydro can be used to store energy, but currently there are very few operating. And there is a growing resistance to building lakes and dams, as well as the cost to aquire land for these.

Battery energy storage is also progressing, but again there are few of these, and the capacity is somewhat small.

There is interest in compressed air storage, but this is actually a suplement to a gas turban plant.

Yes I've heard of H2 storage, but there are none that I know of operating.
 
I think the one thing many people don't understand is the grid is a balanced system. The consumption must be balanced with generation. The two must match or bad things happen.

I know there is some inertia in the grid that allows some percentage of temperary unbalance. But this inertia isen't as great as some people seem to think it is. It is not several hundred mega watts like many wind developers would like us to believe.

That is the reason we call wind non-dispatchable, or non-firm power. It requires a normal or storage source to inversly follow the wind.

Most utilitys seem to top out at inversly following the wind at about 10 to 15% of total generation.
 
Not sure about battery storage.
Isn't that pretty damned expensive and just how quickly can you ramp up demand on a battery?

Pumped Storage schemes would seem to offer some pretty good ramp up response to power demand I would have thought (but i guess it depends on the available head... I can see the Dutch Polders will have to be built with enough head to generate a goodly amount of electricity even at high tide... of course, they will be reclaimig land from the sea as usual.

By the way, I don't see there being a problem with cost.
If there were, we wouldn't be investing tax payers money in wind farms, would we now?
So it stands to reason that whatever is necessary to make wnd farms work will be "necessary" and hence afforded.

The most interesting is probably Cruachan Power Station (
JMW
 
As I understand my grid, frequency is part if the balance. Dispatchers monitor Real Time via GPS type data against clocks running on the grid. As the load increases the frequency is pulled down until the generation capacity catches up. The frequency swing is small. Interfaces between major grids are direct current to prevent one grid from pulling the frequency down on another grid during a brown-out.

As my understanding is very basic, perhaps cranky108 or others can add some sophistication to the technical issues.
 
The ties between grids is DC but not to protect the grids. The three major grids are so large that a small difference in frequency between any two whould cause several thousand Mega Watts to flow between them. The problem with tieing the grids is no single line can carry that much power flow.
The DC allows the control of the flows between the grids.

Actually for a devation of frequency several major generation plants will be adjusted to make up for that difference. Sounds eazy, but currently there can be some large penilitys for inadverent flows.
Most companies are required to balance the in and out flows to keep the grid balanced. The companies that are not required to balance there flows are under the umbrellia of a balancing athorty which keeps the balance.

For major frequency devations customers may be shed to keep the remaing grid balanced. This is followed by a NERC investigation for the cause, and possible penilitys.
 
cranky108,

Do they still have lights bulbs on each circuit to look at the frequency differences?
 
There seems to be some interest in sodium sulfur batteries with wind energy. I talked to an NGK rep a few weeks ago. The price is still quite high - as much or more than the wind turbines themselves.


GE announced a new $100M NaS battery plant in New York, so they must believe there is a market.

Alan
----
"It’s always fun to do the impossible." - Walt Disney
 
Not the newest designs. But they are a good idea to be sure, as a wiring error can cause a 180 degree sync of a generator on a single phase syncscope.

Usually they cheepout and only install a single phase PT on one side of the breaker.

At least someone is looking at the wind storage issue. People should have seen this comming.

 
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