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Texas Power Failure

I calculated peak kW AC produced and average effective sun hours from an insolation calculator.
One-time capital cost (at today's prices) is $0.50/W for inverter and PV panels, $1/W including ground mounts, wiring, etc.
Amortized over 10 years it comes out to $0.05/kWh (if I remember correctly.)
Might have to replace an inverter at that point, and amortized over 20 years that brings it to $0.03 (rather than $0.025) per kWh.
Beyond 10 years time value of money increasingly important, so maybe $0.05/kWh first decade, $0.01/kWh second decade.
If you can keep system cost closer to $0.50/W than $1/W, that's a lot of savings.

My original install was more expensive and 17 years ago, so I amortize over that period and come up with about $0.20/kWh.
Since then I've bought more for upgrades and battery backup.

One can do more complicated math involving cost of capital, but with cash in the bank earning between 0.01% and 2% today, I leave interest rates out of the equation and just divide by operating time, cycles, kWh over a decade.

For batteries, I amortize over cycle life.
My AGM would cost $0.50/kWh if cycled enough to wear out. More expensive as I use them, which is standby waiting for a grid failure.
I apply similar math to Lithium. Commercial lithium batteries used to cost just as much per kWh as my AGM, higher capital cost for more cycles.
Today DIY lithium looks like it can be 1/2 the capital cost of AGM and several times the cycle life.
OK, thanks.
I didn't want to hijack Texas so I created a new thread.
 
Texas is a big place. Some areas get a lot more sun than others. ;)

Everything is bigger in Texas. I know.
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I lived in Houston for 13 years. Been there, done that, got the Fire ant bites to prove it.
 
Sure, but the northern part of texas is between Oklahoma and New Mexico so I doubt it gets less sun than its neighbors up there.

I'm in south Louisiana, about the same latitude as Houston, where prevailing southern winds push moisture in from the gulf and can give us clouds for days.
 
I follow a very good solar /EV program in England and it decimates the excuses made by the PoCo,s in Texas ,
it is called The Fully Charged Show and is presented by a very enthusiastic and energetic guy named Robert Llewellyn
I think you will find this a very intriguing revelation !
This guy is not right.
1. nat gas doubled its out put of power in the big Texas freeze.
2. there were problems or they would have more than doubled there out put
3. Wind and solar production went down.
4.If wind and solar are to do there part in a big freeze if you put up 1 wind mill you would have to put up 2 and let one stay off until the freeze comes and the same for solar.
5. The higher % wind and solar with out there part of the backup the worse of the problem is .
6. With out extra back up power we would have been in even worse trouble.
7. This is just one more point in the foolish wind and solar fairy tail .
 
This guy is not right.
1. nat gas doubled its out put of power in the big Texas freeze.
2. there were problems or they would have more than doubled there out put
3. Wind and solar production went down.
4.If wind and solar are to do there part in a big freeze if you put up 1 wind mill you would have to put up 2 and let one stay off until the freeze comes and the same for solar.
5. The higher % wind and solar with out there part of the backup the worse of the problem is .
6. With out extra back up power we would have been in even worse trouble.
7. This is just one more point in the foolish wind and solar fairy tail .
Here’s an article supporting your comments.


Original article it references is from:


In a nutshell, natural gas increased production 91% from same date 1yr prior while wind reduced its power output by 72% same date 1yr prior.

Different weather conditions, a year later and were there equipment changes, scheduld maintenance outages, ...blah blah so we clearly may not / are not comparing identical situations. But the fact is that natural gas increased power production big time along with solar and coal. Wind was the biggest reduction in power production but nuclear reduced too.

Looks to me there’s plenty of room for improvements in their power production, distribution, and management. So the take away should be, stop pointing tribal click fingers at each other and find / implement solutions so that they mitigate this from happening in the future.
 
I just noticed the south west states get more than Florida. Which seems odd.
Florida would get a higher insolation, but we have those pesky rain storms blotting out the sky from May through November during prime production hours. Not like Corvallis where it rains non-stop for 6 months and seaweed grows on stop signs. More like an afternoon cloud burst that goes away... so the sun can turn the moisture into more humidity. ?
 

The plot thickens!​

Let's do some fact checking (reuters):
  • Wind generates 20% of total electricity in Texas (a lot more than I thought)
  • Solar supplies 1.1%
  • Texas lost 40% of its generating capacity
My thinking?
So, Wind turbines freezing up could have definitely added to the problem. But... wind turbines freezing up points to a lack of maintenance (they have them in Antarctica), same as the gas wells. The failure isn't really gas or wind; it's a human failure.

This article say's only "half" the wind turbines froze, so a 10% contributor at best. So, I'd have to agree with Snopes assessment, the impact from wind turbines freezing wasn't as big as the other problems.

From the ERCOT statement:
Dan Woodfin, senior director for the Electric Reliability Council of Texas (ERCOT), which operates the state’s power grid, said that while ice forced some turbines to shut down just as a brutal cold wave drove record electricity demand, that was the least significant factor in the blackouts. Woodfin also told Bloomberg that the main factors behind the power failures were frozen instruments at natural gas, coal, and nuclear facilities, as well as limited supplies of natural gas.

Here's an interesting similar article saying Germany's renewables were responsible for their February outages (mostly false).
 
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As an Engineer and a citizen I am amazed that in this day and age we have to endure outages, I can fund tin cans to Mars but refuse to invest in our essentials here. I refuse to accept failure, in my business failure means death. We CAN do better, we need to.
 
The point is when it gets very cold you need more power and wind and solar can't go up because they are at 100%. The higher % solar and wind the less flexable the power production .
 
...when it gets very cold you need more power and wind and solar can't go up because they are at 100%. The higher % solar and wind the less flexable the power production ...
That doesn't make renewables less flexible. After all, a 100 MW coal fired plant can't output more than 100 MW just because it's cold.

If anything, solar and wind suffer in flexibility when there isn't any sunshine or wind. But that's a known problem and the general solution is energy storage (similar to having stockpiles of natural gas for a gas facility). That's actually one of my big gripes, you always hear about energy producing solar or wind and hardly ever about storage (although it was nice to see storage in the Gemini project, see post #70). With renewables you always need a balance of production and storage.
 
IMHO, the failure of the TX grid was due to a failure to prepare. They did not implement the recommendations from 2011 for winterizing their power generation system. In an unregulated market, there wasn't any profit in it, and they weren't compelled to do so, so they didn't.

Had they implemented those winterization recommendations, this would likely have been nothing more than a notable freak cold snap with limited power outages and some rolling blackouts with far fewer dead.
 
That doesn't make renewables less flexible. After all, a 100 MW coal fired plant can't output more than 100 MW just because it's cold.

If anything, solar and wind suffer in flexibility when there isn't any sunshine or wind. But that's a known problem and the general solution is energy storage (similar to having stockpiles of natural gas for a gas facility). That's actually one of my big gripes, you always hear about energy producing solar or wind and hardly ever about storage (although it was nice to see storage in the Gemini project, see post #70). With renewables you always need a balance of production and storage.
I said gas they run gas plants below max to have somthing for outages and such. There is little coal around me so don't know
All wind and solar is 100% all the time no way to make more.
 
Generators are a simple solution but TX gets more sun for generating electricity than just about anywhere else in the US.

Um, excuse me but......

Florida is The "Sunshine State". Says so right on the Tags

Texas gets more Hurricanes than Florida. And poor Louisiana !!
 
"California. The climate is right. For business."

 
... they run gas plants below max to have something for outages and such....All wind and solar is 100% all the time no way to make more.

I don't know of any renewables at the utility scale that work that way.

Hydro
For example, hydro you just throttle back on the water volume and it throttles back the power. (ref)

Solar
All new PV solar systems have to follow UL 1741 (went into effect a few years back
and most states have adopted it) that allow the utilities to throttle back solar. My
microinverters throttle from 0 to 100% (ref). But worse case, you could just flip the
switch and stop taking power - that doesn't hurt solar. You can take as much or
as little as you want.
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Wind
Wind turbine's are a bit trickier.

The one thing all wind turbines have in common is some sort of braking feature, for example on the big ones you can rotate the blades angle of attack to vary the power or shut it down for maintenance. They have to have this feature to prevent damage during high-wind.

On a wind farm, typically the farm output is controllable per turbine. If you've ever driven past a wind farm you'll typically see some not spinning... they're usually not broken, they're turned "off" as there's no need for the power. But each turbine is generally 1 to 3 MW, so if you had a 300 MW field of 100x 3 MW wind turbines you could throttle the power anywhere from 0 to 300 MW by activating 0 to 300 turbines.

So, you could easily overbuild renewables just as you do fossil/nuclear plants. But, what makes more sense is to install energy storage. That way you don't need to overbuild for peak demand.
 
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I was really interested in the Texas power debacle just in terms of the technical issues and risk assessment vs. cost evaluations. However, when I tried to find useful information, I kept coming across propaganda that uses the most common trick in the sales profession, the false comparison. For instance, if I go into a fine clothing store to buy a high quality shirt, they are going to show me an $80 shirt that just happens to be 40% off that day, so I can get it for the low low price of $48. They want me to compare the marked price to the price they wish they could sell it for, rather than to the actual value of the item.

So in this energy production propaganda effort, I've seen thinks like the quotes from earlier in this thread:
1. nat gas doubled its out put of power in the big Texas freeze.
natural gas increased production 91% from same date 1yr prior while wind reduced its power output by 72% same date 1yr prior.
or this one I heard elsewhere from some opposite leaning propaganda:
Wind output was actually higher than forecast during the Texas freeze

None of these are relevant comparisons. Natural gas production was higher than a year ago, because a year ago the temperature was mild, and in mild temperatures when demand is low, the for-profit companies shut down the most expensive production. So what they are admitting here is that the electricity providers would rather generate power from wind because it is cheaper. This has no bearing on the reliability of the wind or natural gas infrastructure in freezing temperatures.

On the opposite side, the fact that this winter they had planned some outages of the wind generation capacity, but cancelled those outages due to high demand thus leading to the "higher than forecast wind power production" says nothing about the reliability of the wind generation infrastructure during freezing temperatures.

The one and only metric that really matters is:
How much power generation infrastructure is installed - vs - How much power generation infrastructure was operational when you needed it.

I haven't found any hard data on this. I really wanted to find a timeline of the systemic failures and responses to those failures, but being this industry is privatized in Texas, that information will be obfuscated to the maximum degree out of fear of future financial liability and litigation.
 

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