.

[turbguy + 1,543]

3 hours ago, Dan Clemmensen said:

 It will need to kick in the auxiliary resistance heaters at a temperature higher than the crossover because the house is just too damn cold during an extreme event.

Yup.  That surprised me as well.  Typically those units are small (a hotel room or two).

Hopefully, the bearings in the electric meter are well designed.

I can't imagine the power bill for those power distributors (marketers) at $9/KWH.

Edited April 2, 2021 by turbguy

[Wombat + 1,028]

On 3/29/2021 at 2:22 PM, Dan Clemmensen said:

Your envelope matches mine: on the back of an envelope, 1.1 is the same as 1.3 😀. You were computing for all 10 of the 1 GW generators, which will be on 10 different sites scattered around the state. I was computing for only one of them.  I got 1.3 Bcf per site, which is higher than yours because I started from the EIA's pre-computed national average observed kWh/cf number.  So the storage at each site is about the same as the storage in three smallish CNG carriers.

Since these machines are idle 99.9% of the time, if a less efficient generator is cheaper, then it will be used, and you need even more storage.

It would be much cheaper to just have one or two 500MW gas turbines on standby, plus a few diesel gen-sets, and about 3 GW of batteries. Looks as though that is what will happen anyway?

[turbguy + 1,543]

24 minutes ago, Wombat said:

It would be much cheaper to just have one or two 500MW gas turbines on standby, plus a few diesel gen-sets, and about 3 GW of batteries. Looks as though that is what will happen anyway?

It would be cheaper (IMO) to assure that gas processing facilities submitted paperwork to ERCOT concerning "critical infrastructure" designations to prevemt rolling blackouts at their facility.

I have no idea about what that situation was here.

I would be highly interested, though.

Edited April 2, 2021 by turbguy

[Dan Clemmensen + 1,011]

9 minutes ago, turbguy said:

It would be cheaper (IMO) to assure that gas processing facilities submitted paperwork to ERCOT concerning "critical infrastructure" designations to prevemt rolling blackouts at their facility.

I have no idea about what that situation was here.

I would be highly interested, though.

IMO paperwork is insufficient. You need at least dedicated electrical circuits, and IMO you need dedicated electrical backup generation for those circuits. Basically, power needed to maintain power is in a whole 'nother category, above "critical". According to Ward's excellent video, there were so many "critical infrastructure" circuits already that there was not enough power to "roll" the blackouts. That's cutting it way too fine. Because paperwork is easy to mess up, separate circuits and generation under control of the NG providers is a lot more reliable.

[NickW + 2,714]

On 4/1/2021 at 3:39 AM, Ward Smith said:

Back to the topic at hand. Practical Engineering review of Texas power outage. Should be helpful to some

Good video summarising the situation. Most of that has been discussed here but the presenters puts it into a digestible 15 minute talk. 

[turbguy + 1,543]

10 hours ago, Dan Clemmensen said:

IMO paperwork is insufficient. You need at least dedicated electrical circuits, and IMO you need dedicated electrical backup generation for those circuits. Basically, power needed to maintain power is in a whole 'nother category, above "critical". According to Ward's excellent video, there were so many "critical infrastructure" circuits already that there was not enough power to "roll" the blackouts. That's cutting it way too fine. Because paperwork is easy to mess up, separate circuits and generation under control of the NG providers is a lot more reliable.

True, dedicated circuits would be ideal.

Back-up local generation is also a potential solution.

It ain't gonna happen without imposing costs on someone. 

Unfortunately, it just ain't "built" that way.

What's left?  Communication.

Simple.  Cheap.  Easy.

No excuse for lack of communication.

[Dan Clemmensen + 1,011]

6 minutes ago, turbguy said:

True, dedicated circuits would be ideal.

Back-up local generation is also a potential solution.

It ain't gonna happen without imposing costs on someone. 

Unfortunately, it just ain't "built" that way.

What's left?  Communication.

Simple.  Cheap.  Easy.

No excuse for lack of communication.

This only works if those circuits are sufficiently well isolated from the rest of the grid that power can be supplied to them without also supplying power to a whole bunch of other users at the same time. If it "ain't built" that way, somebody will need to pay for it, and at that point local backup generators may begin to look cheaper. But stringing a dedicated wire along the pipeline right-of-way may be cheaper still.

[turbguy + 1,543]

4 minutes ago, Dan Clemmensen said:

This only works if those circuits are sufficiently well isolated from the rest of the grid that power can be supplied to them without also supplying power to a whole bunch of other users at the same time. If it "ain't built" that way, somebody will need to pay for it, and at that point local backup generators may begin to look cheaper. But stringing a dedicated wire along the pipeline right-of-way may be cheaper still.

It just ain't built that way, and you would require a lot more "stuff" ($$) than just the "wire".

Communication is WAY cheaper.

Edited April 2, 2021 by turbguy

[footeab@yahoo.com + 2,190]

On 3/28/2021 at 9:22 PM, Dan Clemmensen said:

Your envelope matches mine: on the back of an envelope, 1.1 is the same as 1.3 😀. You were computing for all 10 of the 1 GW generators, which will be on 10 different sites scattered around the state. I was computing for only one of them.  I got 1.3 Bcf per site, which is higher than yours because I started from the EIA's pre-computed national average observed kWh/cf number.  So the storage at each site is about the same as the storage in three smallish CNG carriers.

Since these machines are idle 99.9% of the time, if a less efficient generator is cheaper, then it will be used, and you need even more storage.

I did some very brief "internet" surfing so called "research" for a different thread, about 6 months ago on this website, and the modern CGGT reach 80% load in under 5 minutes(under 2minutes generally speaking, but they guaranteed 5 minutes for cold start) and 100% load under 15 minutes.  So, for all practical purposes, expecting ~60+% efficiency overall for backup over a week would be deemed acceptable.  Likewise modern peakers are 40% efficient with a single stage turbine generator. 

Edited April 3, 2021 by footeab@yahoo.com

[Eyes Wide Open + 3,555]

Batterys pave TX future..case closed? 

https://dallasinnovates.com/hunt-energy-networks-new-venture-will-put-50-batteries-across-texas-giving-ercot-a-portfolio-of-energy-generation/

Hunt Energy Network’s New Venture Will Put 50 Batteries Across Texas, Giving ERCOT a Portfolio of Energy Generation

[turbguy + 1,543]

1 hour ago, Eyes Wide Open said:

Batterys pave TX future..case closed? 

https://dallasinnovates.com/hunt-energy-networks-new-venture-will-put-50-batteries-across-texas-giving-ercot-a-portfolio-of-energy-generation/

Hunt Energy Network’s New Venture Will Put 50 Batteries Across Texas, Giving ERCOT a Portfolio of Energy Generation

It's a start, particularly great if the locate them at subs that supply nat gas production (if lack of power to those customers was one of the a root causes).  Don't forget, Elon will do (and has done) some in TX as well.

The article only mentions output, not energy stored (MWh).  Given the images in that article, I would say they are only "good" for an hour's service (+/-).

Batteries are great for smoothing sudden system disturbances, since they can respond within fractions of a second.

Then, again, this is from April 1st...

Edited April 3, 2021 by turbguy

[KeyboardWarrior + 527]

Deleted. Math was screwed up and I noticed @Dan Clemmensen did the math already. 

 

Edited April 3, 2021 by KeyboardWarrior

[KeyboardWarrior + 527]

@Refman If the generator is a CCG plant at 60% then just multiply the first figure by 1.4 instead of 1.6. You get the point 😉

[turbguy + 1,543]

1 hour ago, footeab@yahoo.com said:

I did some very brief "internet" surfing so called "research" for a different thread, about 6 months ago on this website, and the modern CGGT reach 80% load in under 5 minutes(under 2minutes generally speaking, but they guaranteed 5 minutes for cold start) and 100% load under 15 minutes.  So, for all practical purposes, expecting ~60+% efficiency overall for backup over a week would be deemed acceptable.  Likewise modern peakers are 40% efficient with a single stage turbine generator. 

Did you mean CCGT?  The steam side, from cold, will probably take more than 15 minutes to reach full load from a unit start signal. The GT's, no problem with a 5 min start signal to full load.  That rapid a start will consume life of the hot parts somewhat, but that's business

Also, to achieve those high efficiencies, the GT's gotta run pedal-to-the-metal.  Part-load operation will have a penalty.

[turbguy + 1,543]

9 minutes ago, KeyboardWarrior said:

Fairly straightforward to calculate if you know the efficiency of the generator. If we assume 40%, then we'll need 1GW * 1.6 GW of heat to make 1 GW of electricity.

7 days * 1.6 GW * 24h/day = roughtly 270 GWh.

Converting 270 GWh to Btu: 270 GWh * 3600 seconds * 1,000,000,000 W = 9.72 x 10^14 joules.

9.72 x 10^14 joules / 1055.06 joules/Btu = 9212274619453 Btu

1000 cubic feet of natrual gas: approx 1 M btu, so 9212274619453 Btu / 1,000,000 Btu =

about 9.2 million cubic feet of natural gas

 

(1 GWe/1.6 GWt) * 100% = 62.5% efficiency, no?

Combined Cycle plants (sans gas auxfiring on the steam side) get there.

Edited April 3, 2021 by turbguy

[KeyboardWarrior + 527]

Just now, turbguy said:

(1 GWe/1.6 GWt) * 100% = 62.5% efficiency, no?

No, multiplying by 1.6 indicates 40% efficiency. 

[KeyboardWarrior + 527]

@turbguy Wait you're right, the multiplier needs to be different. 

[turbguy + 1,543]

2 minutes ago, KeyboardWarrior said:

No, multiplying by 1.6 indicates 40% efficiency. 

Did you mean 1 GW PLUS 1.6 GW?  That's closer.

Efficiency % is typically output/input x 100%, no?

[KeyboardWarrior + 527]

Just now, turbguy said:

Did you mean 1 GW PLUS 1.6 GW?  That's closer.

Efficiency % is typically output/input x 100%, no?

Yea the multiplier should be 2.4 you're right 

[turbguy + 1,543]

Just now, KeyboardWarrior said:

Yea the multiplier should be 2.4 you're right 

Yeah, I do that kinda mixup all the time. 

We can avoid being a nation of snobs if we are willing to just poke fun at ourselves.  (Besides, there less chance of being sued..).

[KeyboardWarrior + 527]

5 minutes ago, turbguy said:

Yeah, I do that kinda mixup all the time. 

We can avoid being a nation of snobs if we are willing to just poke fun at ourselves.  (Besides, there less chance of being sued..).

If I did that sort of thing as a petroleum engineer my employment might be terminated. Good that I can practice! 😆

[turbguy + 1,543]

30 minutes ago, KeyboardWarrior said:

If I did that sort of thing as a petroleum engineer my employment might be terminated. Good that I can practice! 😆

I used a second set of eye's (aye's).😳

Edited April 3, 2021 by turbguy

[footeab@yahoo.com + 2,190]

2 hours ago, turbguy said:

Did you mean CCGT?  The steam side, from cold, will probably take more than 15 minutes to reach full load from a unit start signal. The GT's, no problem with a 5 min start signal to full load.  That rapid a start will consume life of the hot parts somewhat, but that's business

Also, to achieve those high efficiencies, the GT's gotta run pedal-to-the-metal.  Part-load operation will have a penalty.

Yes, CCGT, and actually the newest one was claiming 80% load in roughly 3 minutes and 95% load in well under 15minutes.  As for lifetime... were claiming that by starting fast helped them for longevity.  Depends on which part they are talking about I am sure... Nothing quite like snowjob salesmen selling snow to Eskimos. 

[Eyes Wide Open + 3,555]

18 hours ago, turbguy said:

It's a start, particularly great if the locate them at subs that supply nat gas production (if lack of power to those customers was one of the a root causes).  Don't forget, Elon will do (and has done) some in TX as well.

The article only mentions output, not energy stored (MWh).  Given the images in that article, I would say they are only "good" for an hour's service (+/-).

Batteries are great for smoothing sudden system disturbances, since they can respond within fractions of a second.

Then, again, this is from April 1st...

It looks like the solutions will be to cut up the larger grid into much smaller micro grids. Perhaps in order to salvage this mass Hodge podge of infrastructure.

It should be interesting to see this being played out, massive investment will be required to stabilize wind generation, and the local communities will end up paying for this stabilization.. Will TX cost average these efforts across the state or will local communities carry this burden independently or perhaps a "windfall" for those targeted communitys's.

Edited April 3, 2021 by Eyes Wide Open

[turbguy + 1,543]

5 hours ago, Eyes Wide Open said:

It looks like the solutions will be to cut up the larger grid into much smaller micro grids. Perhaps in order to salvage this mass Hodge podge of infrastructure.

It should be interesting to see this being played out, massive investment will be required to stabilize wind generation, and the local communities will end up paying for this stabilization.. Will TX cost average these efforts across the state or will local communities carry this burden independently or perhaps a "windfall" for those targeted communitys's.

That "break-up" will actually hamper reliability, as power cannot then be transmitted between microgrids. 

If you "connect" the microgrids together to share, you just end up with the "macro"grid you started with. 

"Islanding" of connected microgrids that serve critical infrastructure is just the same as designating which circuits are considered critical infrastructure that need to be exempt from load shedding actions. 

Then, when you want to tie them back together, you gotta synch them up (match voltage, frequency, and phase). Sometimes trivial, sometimes not.

And I agree, it IS a hodge-podge, as they grew over many, many years with multiple owners of all the pieces parts.

Massive investment is required for any generation expansion.

 

Edited April 4, 2021 by turbguy