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A Little Arithmetic: The Costs Of A Solar-Powered Grid Without Fossil Fuel Back-up
Manhattan Contrarian ^ | 29 Jul, 2021 | Francis Menton

Posted on 08/01/2021 4:57:39 AM PDT by MtnClimber

Yesterday’s post made the point that states or countries seeking to march toward 100% “renewable” electricity don’t seem to be able to get past about the 50% mark, no matter how many wind turbines and solar panels they build. The reason is that, in practical operation, due to what is called “intermittency,” no output is available from the solar and wind sources at many times of high demand; therefore, during those times, other sources must supply the juice. This practical problem is presented most starkly in California, where the “renewable” strategy is based almost entirely on solar panels, with only a very small wind component. Daily graphs published by the California Independent System Operator (CAISO) show a clear and obvious pattern, where the solar generation drops right to zero every evening just as the peak demand period kicks in from about 6 to 9 PM.

Commenter Sean thinks he has the answer: “Given the predictable daily power generation cycle of solar in sunny places like California and the predictable daily demand which peaks in the evening perhaps solar generators should be required to have electricity storage equivalent to the daily generation of their PV system.”

I thought it might be instructive to play out Sean’s idea to see just how much solar generation capacity and storage it would take to make a system out of just those two elements that would be sufficient to fulfill California’s current electricity requirements. Note: this is an exercise in arithmetic. It is not complicated arithmetic. There is nothing here that goes beyond what you learned in elementary school. On the other hand, few seem to be willing to undertake the effort to do these calculations, or to recognize the consequences.

We start with the current usage that must be supplied. Currently, the usage ranges between a low of around 30 GW and a high of around 40 GW over the course of a day. For purposes of this exercise, let’s assume an average usage of 35 GW. Multiply by 24, and we find as a rough estimate that the system must supply 840 GWH of electricity per day.

How much capacity of solar panels will we need to provide the 840 GWH? We’ll start with the very sunniest day of the year, June 21. California currently has about 14 GW of solar capacity. Go to those CAISO charts, and we find that on June 21, 2021, which apparently was a very sunny day, those 14 GW of solar panels produced at the rate of about 12 GW maximum from about 8 AM to 6 PM, about half that rate from 7-8 AM and 6-7 PM, and basically nothing the rest of the time. Optimistically, they produced about 140 GWH for the day (10 hrs x 12 GW plus 2 hrs x 6 GW plus a little more for the dawn and dusk hours). That means that to produce your 840 GWH of electricity on a sunny June 21, you will need 6 times the capacity of solar panels that you currently have, or 84 GW. When 7 PM comes, you’ll need enough energy in storage to get you through to the next morning at around 8 AM, when generation will again exceed usage. This is about 13-14 hrs at an average of 35 GW, or around 475 GWH of storage.

That’s June 21, your best day of the year. Now let’s look at a bad day. For the past year, a good example would be December 24, 2020, which besides being one of the shortest days of the year, must also have been rather cloudy. Production from the existing 14 GW of solar capacity averaged only about 3 GW, and only from 9 AM to 3 PM. That’s 18 GWH in that window (3 GW x 6 hrs). Then there was another about 1 GWH produced from 8 to 9 AM, and another 1 GWH from 3 to 4 PM. About 20 GWH for the whole day. You need 840 GWH. If 14 GW of solar panels only produced 20 GWH for the day, you would have needed 588 GW of panels to produce your 840 GWH. (14/20 x 840) That 588 GW of solar panels is some 42 times your existing 14 GW of solar panels. And when those 588 GW of capacity stop producing anything at all around 4 PM, you are also going to need at least 16 hours worth of average usage in storage to get yourself to 8 AM the next morning. That would be around 560 GWH of storage.

So you can easily see that Sean’s idea of providing storage “equivalent to the daily generation of the PV system” doesn’t really get to the heart of the problem. Your main problem is that you will need capacity of close to 15 times peak usage (nearly 600 GW capacity to supply peak usage of around 40 GW) in order to deal with your lowest-production days of the year.

Cost? If you assume (charitably) that the “levelized cost” of energy from the solar panels is the same as the “levelized cost” of energy from a natural gas plant, then this system with 15 times the capacity is going to cost 15 times as much. Plus the cost of storage. In this scenario, that is relatively modest. At current prices of around $200/KWH the 560 GWH of storage will run around $112 billion, or around half of the annual budget of the state government of California.

But you may say, no one would build the system this way, with gigantic over-capacity in place just to cover the handful of days in the year with the very lowest solar output. Instead, why not build much less solar capacity, and save up power from the summer to cover the winter. Since the average output of the solar facilities in California is about 20% of capacity averaged over the year, then you ought to be able to generate enough power for the year with capacity of about 5 times peak usage, rather than the 15 times in the scenario above. You just will need to save up power all the way from the summer to the winter. Oh, and you will need a huge multiple more storage than for the one-day-at-a-time scenario. If 180 days per year have less production than usage, and the average shortfall of production on each of those days is 300 GWH, then you will need 54,000 GWH worth of batteries (180 x 300). At $200 per GWH, that will run you around $10+ trillion. This would be about triple the annual GDP of the state of California.

But don’t worry, batteries to store power for six months and more and release it without loss on the exchange don’t exist. Maybe someone will invent them in time for California to meet its 2030 renewable electricity targets.

Any reader can feel free to check my math.

I just can’t believe that anybody talks about this as something remotely connected to reality.


TOPICS: Business/Economy; Science; Society
KEYWORDS: battery; communism; electricity; energy; greenism; powergrid; solar
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To: freedumb2003

California, Oregon, Washington ... I could live with that.


21 posted on 08/01/2021 6:11:19 AM PDT by throwthebumsout
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To: MtnClimber
Batteries are a non-starter because energy doesn't like to be stored. It's always a costly proposition and usually involves double-conversion, converting the source electrical energy into some other inherently storeable form, then converting that back to electrical energy on demand. Such as in a lead-acid battery, which stores chemical energy that's been converted from electrical. And there's always an inefficiency inherent in each conversion.

The operative phrase is "spinning reserve." In order for your grid to remain stable, you need a "mirror" of sorts. You need 80-90% of your "renewable" capacity in conventional power plants, and that 80-90% must be in a condition known as "spinning reserve," from which it can kick in and go online instantaneously when the renewable source craps out.

The newer coal-fired generating stations are very nearly zero emissions but in the process of making them so clean they also were made unsuitable/unable to operate in spinning reserve. And nuclear plants only have two speeds: off and WFO. So there's no point having one in spinning reserve because it costs the same whether it's online or not.

The insanity is that they've always known it wasn't possible to build a stable grid purely off "renewables," that that plan was always going to necessitate a "ghost" power system capable of producing >3/4ths of the "primary"/renewable system's maximal output, and that that spinning reserve/ghost/back-up system would cost exactly as much to build and only slightly less to operate than as if it were online full-time.

And you're wasting all this money on a mirror of back-up power plants entirely so you can beat your chest and brag that your primary power sources run on "renewables."

Except for the ghost/back-up system, which is all that makes the "renewable" generating stations a functioning component in a stable power grid.

22 posted on 08/01/2021 6:13:10 AM PDT by Paal Gulli
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To: MtnClimber

I greatly appreciate the author’s deep dive into the facts, logic, and math of this situation. I believe it doesn’t even require the use of any of those mental resources to know this Greenie wet dream doesn’t even pass either the smell test or common sense.


23 posted on 08/01/2021 6:15:30 AM PDT by T-Bird45 (It feels like the seventies, and it shouldn't. )
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To: MtnClimber

The true answer was established when America had a higher level of math and scientific genius:splitting of the atom/harnessing the given energy.


24 posted on 08/01/2021 6:17:41 AM PDT by shanover (...To disarm the people is the best and most effectual way to enslave them.-S.Adams)
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To: Bernard
And of course the default solution is the "North Korea Scenario". Just turn off the power for everybody except the elites. When the supply starts to replenish, let the plebs have a little, at least for a while.

We may scoff at this notion but I bet you they've discussed it.

And I promise you this...the elite will have continuous power. Why? Because they're "important" and your not.

25 posted on 08/01/2021 6:21:30 AM PDT by ealgeone
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To: MtnClimber

Let them learn the hard way if they won’t listen to reason or can’t read. This really isn’t that hard to understand. This scenario is for California, the Sunshine state. What will it take in other places where the sun doesn’t shine nearly as much? Where I live is one of those places & we have a large solar array here for a small community. I have never heard a peep out of anyone as to whether this thing is even online,if it is meeting any needs,who is on it, it’s available output, etc., etc. Is it supposed to be a deep dark secret? If so, that would certainly be only because it’s not meeting the needs.


26 posted on 08/01/2021 6:23:33 AM PDT by oldtech
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To: MtnClimber

——this is an exercise in arithmetic-—

But, but........ Arithmetic is math. girls and black men can’t do math. It ‘s therefore fake news.

That’s the left wing view propounded by the media

Cultural analysis


27 posted on 08/01/2021 6:26:01 AM PDT by bert ( (KE. NP. N.C. +12) Like BLM, Joe Biden is a Domestic Enemy )
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To: BradyLS
It looks right. The 30-40 GW is the flow rate of energy (aka the power) while multiplying it by time gives you the total energy 840 kWh. The problem is that we are used to flow rates being in amount per time but in this case the units of watts and kilowatt-hours don't match that because the flow rate is the base unit.

If you think of it as 35 miles per hour (the flow rate) multiplied by 24 hours to get 840 miles you can see what is happening.

28 posted on 08/01/2021 6:27:51 AM PDT by KarlInOhio (Police should refuse duty at NBA venues. Let them wallow in their desired chaos without police.)
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To: Montana_Sam

Fantasy / reality = angry libtards


29 posted on 08/01/2021 6:31:08 AM PDT by RckyRaCoCo (Please Pray For My Brother Ken.)
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To: KarlInOhio

I can understand that. Then a GW is the unit for a day and a GWH is 1/24 of a GW. At least as far as the math in the article goes.


30 posted on 08/01/2021 6:36:08 AM PDT by BradyLS (DO NOT FEED THE BEARS!)
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To: freedumb2003

Flip the equation. It all works if most of us are dead.


31 posted on 08/01/2021 7:01:00 AM PDT by Noumenon (The Second Amendment exists primarily to deal with those who just won't take no for an answer. KTF)
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To: MtnClimber
In Ill-Annoy, an illegal battery recycling center had a simple roof leak which lead to a major fire lasting weeks with the attendant environmental impact of the leak of lithium and fire bi-products.

Days later, a 'legitimate' battery facility that backs up a windmill farm also had a very serious fire. Lithium batteries don't like water and really don't like heat.

The joke about calling some of these alternate energy sources "sustainable" in large measure are NOT sustainable in the sense of reliability and constancy.

Can someone name one steel mill or foundry that is powered solely by wind or solar?

32 posted on 08/01/2021 7:02:45 AM PDT by SERKIT ("Blazing Saddles" explains it all.......)
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To: MtnClimber

But don’t worry, batteries to store power for six months and more and release it without loss on the exchange don’t exist. Maybe someone will invent them in time for California to meet its 2030 renewable electricity targets.
***They are invented. There is an entrenched opposition.
https://freerepublic.com/tag/lenr/index


33 posted on 08/01/2021 7:13:18 AM PDT by Kevmo (Right now there are 500 political prisoners in Washington, DC.)
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To: BradyLS

? 35 was the writer’s (rough) average for each hour of the 24 hour-long day.


34 posted on 08/01/2021 7:24:14 AM PDT by Robert A Cook PE (Method, motive, and opportunity: No morals, shear madness and hatred by those who cheat.)
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To: MtnClimber

Note: this is an exercise in arithmetic. It is not complicated arithmetic. There is nothing here that goes beyond what you learned in elementary school.
***They are not teaching that level of math in public schools. The closest I came to tackling these kinds of math treatments was in physics, and you don’t see the ordinary students in those classes.


35 posted on 08/01/2021 7:25:03 AM PDT by Kevmo (Right now there are 500 political prisoners in Washington, DC.)
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To: alloysteel

They want green power until they realize how much it costs. But by then it will be too late.


36 posted on 08/01/2021 7:26:03 AM PDT by Kevmo (Right now there are 500 political prisoners in Washington, DC.)
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To: MtnClimber

“I just can’t believe that anybody talks about this as something remotely connected to reality.”

these are the same people that believe in unicorns - and, sadly, we’re letting them run our lives. Maybe we are the dummies?


37 posted on 08/01/2021 7:26:29 AM PDT by aquila48 (Do not let them make you care! Guilting you is how they control you. )
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To: Paal Gulli; Tolerance Sucks Rocks; Red Badger; Kaslin

For renewing your green energy approximations.


38 posted on 08/01/2021 7:26:38 AM PDT by Robert A Cook PE (Method, motive, and opportunity: No morals, shear madness and hatred by those who cheat.)
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To: MtnClimber

This totally ignores the conversion to electric vehicles. Average usage will jump 10 -15 GWH and this will occur primarily during the non producing hours, significantly increasing the storage requirements.


39 posted on 08/01/2021 7:36:10 AM PDT by CMAC51
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To: Paal Gulli

“... from which it can kick in and go online instantaneously when the renewable source craps out.”

Another solution is to instantaneously turn off the power to millions of household as is done in California.

See, you just got to think out of the box.


40 posted on 08/01/2021 7:37:45 AM PDT by aquila48 (Do not let them make you care! Guilting you is how they control you. )
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