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[Tim McCulloch]

It all matters. Less is less.

Ike, my observation is that nobody who pays the bills of touring gives a rat's ass about less... until it means an entire truck is struck from the tour.  My further observation is that the space and weight saved by modern loudspeaker systems and IEM rigs, etc, is that any savings of space/weight in trucking are immediately taken by video/lights and artist carpentry "gags" like Carrie Underwood's flying pickup truck, Bon Jovi's video robots or Taylor Swift's flying "B stage".  These days tours have more trucks, not fewer, and the proportion used to transport audio is smaller; we've done our bit now it's up to departments to compact their presence and we both know that's never gonna happen because audiences "hear" with their eyes.

A bigger carbon impact will probably be found in how attendees travel to a show, what they buy/consume while there, etc.

Tis a puzzlement.

[Chris Hindle]

It all matters. Less is less.

If I tell production I only need 35 feet of truck for audio, they'll likely say "Oh good, we can go with that bigger stage rig" or "Great, we can carry another 10 sticks the lampies wanted."
One way or another, the trucks roll stuffed.
Chris.

[Stephen Swaffer]

Maybe you can help me with one other factor - every time I drive by wind farms, only a minor fraction of them are actually running, and this is on days with seemingly adequate wind. I realize there is a minimum threshold of wind needed to get them turning and I realize there is some upper limit to the usable wind before the turbine needs to shut down to not blow up, but it sure seems that they’re off a lot more than that? It’s got to be hard to make money when they’re off 50%+ of the time.

You mention in another post the unknown impact of extracting a bunch of wind energy from the environment. This is very interesting to me - certainly cities affect weather patterns with tall things of warmer than ambient temperature sticking up high enough to disrupt wind, and I know that trees have a major impact on wind speed, which is generally seen as a positive factor, but I haven’t heard anyone speculate on impact due to turbines.

My suspicion is capacity-specifically excess capacity.  It would seem the grid could absorb it-but I was told by someone that worked in the industry and claims to know  that it takes 8-10 hours to spin up a steam turbine plant.  He claims, they burn off a significant amount of excess energy simply because people wouldn't be happy if lights go out when the wind dies down.  I'm sure there is a lot of management behind the scenes.  It would be interesting to know what percentage of theoritcal capacity is actually usable.

It's pretty common for the wind to drop significantly at sundown.   These are things the old timers that spent a great deal of time outside farming knew from experience-that knowledge and understanding is not so universal today.

[Bill Meeks]

My suspicion is capacity-specifically excess capacity.  It would seem the grid could absorb it-but I was told by someone that worked in the industry and claims to know  that it takes 8-10 hours to spin up a steam turbine plant.  He claims, they burn off a significant amount of excess energy simply because people wouldn't be happy if lights go out when the wind dies down.  I'm sure there is a lot of management behind the scenes.  It would be interesting to know what percentage of theoritcal capacity is actually usable.

It's pretty common for the wind to drop significantly at sundown.   These are things the old timers that spent a great deal of time outside farming knew from experience-that knowledge and understanding is not so universal today.

I worked in electric power generation for my entire career - specifically at a nuclear power plant. You are on the right track with your assessment, but one fact is a little off. Fossil fueled plants can rather quickly ramp up or down in generation capacity, but it is still measured in tens of minutes usually for very large swings of 200 MW or more. They can do more modest output swings rather quickly, though. Nuclear plants are always what are called base load generators. They run at 100% 24-hours a day. They cannot make quick power changes. In fact, the type of plant where I worked (a boiling water reactor) took up to three full days to reach 100% output after startup from a refueling outage.

The electrical grid is a very complex animal that must always be precisely balanced such that generation equals load exactly. Too much generation and the frequency (60 Hz in the USA) drifts up and motors can be damaged. Too little generation for the connected load results in voltage sags and a drop in frequency (both also damaging to electrical equipment such as motors). All the electric generators in a region are connected in parallel so they can share serving the load. This is true in the US at the grid level where you have a handful of regional power grids all connected to each other with large tie lines. Each utility in a region is assigned a load control area that it is responsible for (responsible for matching generation to load within their area). The utility will monitor frequency and the direction of power flow (into their system or out of their system) to determine if their generation is matching their load. When there is a disturbance on the grid that results in lost generation, each connected utility is responsible for providing up to a certain amount of "free" electricity to help rebalance the grid. The connected utilities on the grid provide extra capacity to their struggling neighbor while the utility where the disturbance originated recovers and adds generation of their own.

Consider this example. Utility A suddenly has a major coal-fired power plant trip offline and 600 MW of generation disappears instantly from the grid. Now there is more load than generation and the grid frequency begins to sag (a very small amount, but it does decrease). All the connected utilities on the grid see this sag in frequency and know that generation is no longer sufficient for the load. Each utility checks the power flows on its grid inter-ties (its connections to neighboring utilities). Utility A sees a decrease in frequency and it also sees power flowing into its system from its neighbors. Utility A's neighbors also see the decrease in frequency but see power flowing out of their systems into Utility A. Thus the computers controlling Utility A's grid calculate that Utility A needs to add generation. The other utilities' computers know the problem is not theirs, but they are obiligated to contribute their share of the missing 600 MW back onto the grid until Utility A can bring on that much new generation. This "share of free electricity" for each utility is called the ACE (Area Control Error). The amount of ACE a utility is responsible for is determined by the size of the utility. The bigger the utility, the more MW of electricity it must provide to correct an ACE.

Now how does this relate to windmills and solar? In a word, reliability! The wind can, and does, suddenly stop blowing. Clouds can, and do, suddenly shade solar cells. Both conditions result in loss of generating capacity. Now the grid is unbalanced, and the missing generation has to come from somewhere. If everyone is using just wind and solar for generation, the grid could be out of luck. A windmill operator can't just "send a little more wind to the blades" to increase generation at a windmill site. You get whatever wind there is, and that's that. With a fossil-fuel power plant, it's a simple matter to adjust the coal feed rate or open up the natural gas valve a bit to generate more heat and thus more steam and finally more electrical generation. It is a trivial and near instantaneous event for a large coal-fired plant to pick up 25 MW to 50 MW of load. It only takes a few other plants doing this to easily absorb that 600 MW capacity loss in the previous example. Solar and wind really can't do this today until you have reliable large scale storage batteries and inverters. This is why I don't see fossil-fuel plants going away entirely anytime soon. Solar and wind just don't have adequate "spinning reserves" unless you way overbuild both and have complexes of wind and solar generation just sitting there doing nothing until the few times a year they are needed. They are not really dependable enough to provide base load. Only nukes, fossil and hydro can do that (and even hydro has some limitations due to droughts).

My description above was highly simplifed. If this techy stuff is interesting to you, here is a link to a PDF document from NERC explaining all the nitty-gritty details of how the US power grid is balanced and maintained.

https://www.nerc.com/docs/oc/rs/NERC%20Balancing%20and%20Frequency%20Control%20040520111.pdf

One final parting thought: a typical wind turbine generates 1.5 - 3 MW (megawatts) of electricity. The nuclear plant where I worked generated 1850 MW (megawatts) of electricity 24 hours a day for up to 24 months straight before shutting down for refueling. Come rain, sun, snow or whatever, we just kept on generating. A wind turbine can't do that and neither can solar today. Also, it would take 616 wind turbines (at 3 MW each) to replace just the single nuclear plant where I worked. And to put the amount of MW needed by a typical large utility in perspective, my company routinely needs 24,000 MW or more of electrical generation on a typical August afternoon to supply the customers' needs. That's a heck of a lot of wind turbines ...  .

[Jonathan Johnson]

One final parting thought: a typical wind turbine generates 1.5 - 3 MW (megawatts) of electricity. The nuclear plant where I worked generated 1850 MW (megawatts) of electricity 24 hours a day for up to 24 months straight before shutting down for refueling. Come rain, sun, snow or whatever, we just kept on generating. A wind turbine can't do that and neither can solar today.

And when the wind stops blowing, it's not just one 3 MW turbine that goes offline.

The wind farms in the Columbia River Gorge and Columbia Basin of eastern Washington and Oregon states are capable of a total of over 4,500 MW (Feb 2017 estimate). When the wind stops blowing in that region, that is an enormous amount of generation capacity that must be made up quickly. Granted, it might not all go offline at once (the region is quite large), but the physical geography means that it pretty much all depends on the same winds.

The Columbia River also provides a hydroelectric generating capacity of over 34,000 MW (July 2017), which is the bulk of the generating capacity on the Pacific Northwest grid. When the wind farms are operating, those dams have to hold equivalent capacity (up to 4,500 MW; ~13% of hydro capacity) in generating reserve, so they can respond to the sudden loss of wind turbine capacity. (Hydrocarbon-fueled facilities also are managed to provide reserve capacity, and there are hydro facilities on other northwest rivers, though I don't know what those capacities are.)

A great advantage of hydroelectric generation is its ability to respond almost instantaneously to changes in demand by opening or closing the wicket gates feeding water to the turbines. Direct combustion facilities (internal combustion; gas turbine) can also respond almost instantaneously, but hydrocarbon-steam facilities have lag time as it takes a little while for the steam head to build or cool. Also, there's the factor of water being a renewable resource as compared to hydrocarbon fuels which may be finite, giving hydroelectric another advantage.

[Stephen Swaffer]

I do see some positives to solar in my area-though the ROI is not anywhere near justifying the initial investment for my company (we really looked hard at it)-even when subsidized.

In my area, (Iowa-rural) there is a widely distributed load, plenty of hog confinements, etc with nice big flat roofs made for solar panels.  We also occasionally have "brownouts"-voluntary interruptions in use that are incentivized-and those are usually in the afternoon on bright sunny (hot!) days-when solar is producing at its best. 

So the extra capacity is being generated closer to point of utilization and peaks when needed most-which primarily helps the POCO with its grid management.

I guess my skepticism of wind power was generated by the phone call last spring asking what I thought of a double digit rate increase.  I asked why the increase-their answer was they were investing in wind power to save us all money.  I asked if that meant my rates would eventually go down-anyone wonder about that answer??  Can someone can explain how increasing my electric rates saves me money?

[Frank Koenig]

https://www.nerc.com/docs/oc/rs/NERC%20Balancing%20and%20Frequency%20Control%20040520111.pdf

Bill, thanks for the explanations and link (I need something to read). A quick skim shows that the water analogy lives on 

--Frank

[Bill Meeks]

Bill, thanks for the explanations and link (I need something to read). A quick skim shows that the water analogy lives on 

--Frank

You're welcome. I was always fascinated by the complexities of electric grid management. It gets really involved when you have to worry about VARs and the impact of capacitance and inductance on long high voltage transmission lines (500 KV and above especially). Also a lot of techie stuff goes into scheduled interchanges of power where one utility finds it cheaper to buy power from another utility versus generating it themselves. This can be an hour-by-hour decision at times as it depends on what the tie lines can handle and what generation sources the buying utility has available versus what the selling utility has available.

It always irritates me somewhat when folks make a lot of noise about how wonderful wind and solar are without fully understanding the negative impacts such widely distributed unreliable generation sources can have on the stability of the electric grid. The folks pushing that agenda frequently omit fairly covering the downsides such setups cause for grid operators.

[ProSoundWeb Community]