Hi Roddy: Seems like you are arguing with me.
Yeah, thanks for making my original point: both charging and discharging are important functions, and they don’t both take place at the same time, and the discharging function is the only one that produces electricity, and since that only last for a couple of hours per day, the storage facility is an expensive power plant that is only used less than 10% of the time. .
Which numbers are “waaay out”?
My “pop fact” on German energy markets is just what I hear on the financial and news channels. They keep telling us that Germany shut down too many coal and gas power plants in favor of wind and solar, electricity prices soared in response, and that now that they allowed themselves to become dependent on Russia for natural gas supplies, with the Ukraine conflict, Russia is not shipping enough natural gas to Germany, and now Germany is worried about people freezing to death next winter. Supposedly, Germany is planning to convert stadiums into emergency warming shelters for all the freezing people. That’s just what we hear on the news - so what are the real facts, if you know?
One thing I’ve considered lately is all the time wasted discussing AWE online for the last 14 years. Seems like there is nothing left to say, so we’re applying our armchair-genius-level-thinking to all sorts of other (related) topics, like energy storage. I noticed interesting similarities between probably-unworkable energy storage ideas, like concrete-block-reeling, to kite-reeling.
Seems like there really is little to no real “news” in AWE anymore (if there ever was).
I mean, a couple of years ago the “big news” was working factories were producing AWE systems and had just begin shipping them around the world. What ever happened to that?
I know, I know, we’re not supposed to ask any questions, just go along to get along. Sure, we must now have a burgeoning “industry” with an ever-increasing adoption of AWE systems, right? Powering hundreds of homes? Or was that all more wishful-thinking news-of-the-future, getting just a bit ahead of reality? What about all the “disaster relief” systems? Where are they today? Relieving disasters? Oh, wait - newsflash - we’re having the 13th annual “conference” - where the true-believers preach to the choir? So what happens next? Any AWE systems in regular operation yet? I know I’ve been asking this for at least a decade. Yeah I know, everyting I say must be wrong. It’s OK, I can take it. 
Yep,
Thanks for highlighting
There’s something I can do (and not do) to save my energy and enjoy a more productive life
Thanks Doug
WHAT’S HAPPENING WITH GERMANY’S NUCLEAR PLANTS?
Nuclear-fired power plants, which still supplied 12% of Germany’s gross electricity generation in 2021, remain controversial in Germany, which decided to shut them down after Japan’s Fukushima disaster in 2011.
As a result wind was favored, but as it is intermittent, a backup with gas and coal was required, leading to an increase of dependence on supplies from Russia, and an increase in CO2 emissions.
Now Germany: 280 g; France: 94 g.
Apart from that, batteries are possible for individual use or temporary storage, not for massive storage (see the very low or zero battery storage values on the link above) which is supplied by clean pumped-storage hydroelectricity, or fossil backup as for Germany.
Hi Pierre: Yes how could I have left out the nuke plant shutdown? Also a big factor. In response to Fukushima. Unbelievable that Japan made such a mistake, given their location in a strong Earthquake zone and Tsunami zone. Just goes to show you, nukes are completely safe - unless something goes wrong! A lot of these problems seem so artificially-created, with so many “convenient” coincidences, it makes one wonder if there is a hidden agenda. (???)
The good professor (Crackpot) is at it again:
He’s just solved all the problems of wind energy!
The good professor also spent some time at GE:
Molten Salt Battery - transportation revolution:
Today GE has not been doing so well, despite being a major wind turbine manufacturer. They recently decided to split into 3 separate companies. Give it a few more years, and the next genius will probably decide to re-combine the 3 separate companies again.
Shouldnt such a breakthrough get it’s own thread?
Still; going after clueless people is easy. Pointing a path into the future is the hard part. Im not sure if you just concluded HAWT is the pinnacle of wind power, or there may be something better [at least for some uses] out there. That is what would interest me more.
You know Doug’s answer well.
All roads lead to SuperTurbine ™.
Hi Tallak:
The reason I posted these items I had just, by luck, come across within an hour or so, is to illustrate how easy it is for teams we would assume knew better, to chase whacky ideas and talk about them in all seriousness, while those of us with just a little more knowledge or common sense can immediately see how silly they are. I mean, Jeff Immelt, head of GE, promoting a molten salt battery for cars? Really, you are going to sit there while a 1500 lb. battery pack is heated up to the temperature of a pizza oven. THEN you are free to drive? Sure, real sensible, let’s spend a quarter billion dollars on it!
Or these guys with another vertical-axis turbine. But not a good one. A really goofy-looking one, with way too much rotor solidity. Part Savonius with cloth sails? And you notice their renderings show a thin floating foundation, hoisting a heavy concrete(?) weight. But there was no float big enough to float such a weight shown. Maybe they hadn’t thought it through that far yet. But at least they were “educated” to the point that they “knew” the vertical-axis turbine was a better choice. And they “knew” it would be cheaper, AND a better return on capital because it could keep working in ridiculously strong storms! Because big storms are the best time to make a lot of wind energy, especially at sea! And it’s also a good idea to provide a huge generator to take advantage of those storms, even though your turbine would be dragged down by a way-too-big generator 99.8% of the time. These guys are geniuses. Reminds me of how AWE people all assumed we’d be harnessing the Jet Stream but only years later started calculating how much the tether would weigh… How did these Professor Crackpots “know” their turbines would keep working at 40 m/s winds? Because they had never built or run a wind turbine in their entire lives, so they just thought it “looked” like it “should” - I guess…
I wonder if they had done any back-of-the-envelope calculations on how much energy their weight could store? Let’s see, energy = weight x height, OK here’s an easy calculator:
Allright, 1000 kg x 300 m = 0.82 kWh, (but then you’d have to subtract the volume of water the weight displaces, some water friction, cable friction, motor/generator/gearbox efficiency. Maybe you could get a half a kWh. But offshore turbines are into the MegaWatts, and you’d need enough flotation to buoy that correspondingly huge amount of mass. And then here is another thing about the Professor Crackpot Syndrome: always ruining a god invention by adding a bad invention. If a floating island with reeling weights for energy storage is a good idea, why “ruin” it with a vertical-axis turbine? If it is a valid component, it should stand on its own as an energy storage idea. This is where investors should be smarter. They tend to swallow a story that a known bad idea should be a great idea if it is combined with an unknown idea. “All-ya-gotta-do-is” reasoning. Astute investors would start with examining the two parts of the idea separately - is either one valid?
Anyway, we should all get good at debunking goofy energy ideas, starting with our own. We all need to spend time debunking our own ideas more than others, but debunking others gives us good practice.
For grid storage, I still think lithium batteries are a good choice. Especially with the development of technology in recent years, the price is getting cheaper. In the past, it might cost more than $10,000 to install a lithium battery energy storage system. And the installation is complicated, but now 200kw energy storage batteries have become a ready-made part. If there are enough batteries, I believe we can maximize the utilization of solar energy.
Gravity storage in an aquatic environment
DOI: 10.13140/RG.2.2.33141.44006
Description and figures
Gravity storage would be significantly easier in an aquatic environment, where the water depth acts as a structure, and uncalibrated sandbags are sufficient to provide the necessary mass. Variants with hydrogenerators are also described, but they are more complex, expensive, and probably less efficient. In pumped-storage hydroelectric plants, water falls onto the turbines and drives them. In gravity storage using hydrogenerators as masses, the turbines themselves descend into the water, rotating and generating electricity. These storage methods can be combined with electricity production using kites in pumping (yo-yo) mode.
See also Latest gravity storage article.
An Ocean Gravity Storage project was initiated a few years ago.
It seems to me that a fixed mass that rises and falls without being detached is simpler to manage, even if the barge needs to have a larger capacity.
Well, here we go again, one more crackpot pile of false statements to deconstruct, in one more futile attempt to teach the innocemt, naive children to think!
- Energy Storage! “All ya gotta do is” build several MORE power plants. to rationalize your initial power plant that can’t provide baseload power, or even just spinning reserves!
- I’m seeing a newly-identified “symptom” of “The Professor Crackpot Syndrome”: Videos with flowery music and no narration. We saw this just a few days ago, with some other recent videos provided by Pierre.
- My very FIRST thought was these people must be mathematically-challenged - i.e. incapable of 5th grade arithmetic: How much energy can they store??? Such calculations are trivial, but that is far beyond the capabilities of most armchair energy inventors.
- They say 4000 lbs. of concrete at 4000 meters provides equal energy as 2000 lbs of batteries. OK let’s show that they are, as usual, either completely stupid, or outright lying!: a) So they are saying a Tesla weighing 2 tons can’t climb 12,000 feet? With only 1/2 ton of batteries??? or, b) 4000 lbs. x 12,000 feet = 48,000,000 foot-pounds. Dividing by 550 lbs, yields 87272 horsepower for 1 second. Dividing by 3600 seconds gives us 23.23 horsepower, for an hour. multiplying by 745.7/1000 gives us 18.08 kiloWatt-hours. But a Tesla battery can hold 100 kWh, and it only weighs 1/2 ton. So 1 ton of batteries can hold 200 kWh! So, as I suspected, they are off by more than an order of magnitude in their initial (lack of) calculations! And this is just the first wrong thing I saw in 1 second!! And that doesn’t even include floatation effects nor water resistance to motion.
- That could power one home for 2 or 3 hours.
- So it takes me half an hour to explain what I can see in 1 second…
- This is one more version of the (debunked) cranes lifting concrete blocks for energy storage idea…
- Guys, there is endless complete idiocy to be found on today’s internet - doesn’t mean it’s all factual, or worth your time examining. There, I’ve done my part for today…
That best-case scenario of storing less than 10% of what is claimed does not take into account the inefficiencies of the motor as a motor, the motor as a generator, water friction, reduced ballast weight from flotation, line friction and bending around drums, maneuvering the lines using underwater drones, etc. etc. etc.
And like all energy storage schemes, it can only output energy a fraction of the time. while needing to spend a lot of its time just storing energy, then waiting to be used, rather than providing energy. This all leads to multiple redundancy in building multiple powerplants of a given nameplate power capacity as a substitute for a single baseline power plant, multiplying expenses and resource wastage several times over. All in all a huge waste of resources.
So 1 ton for 200 kWh, so 200 Wh/kg.
1 ton of concrete drops from 4000 m. Using formula: 1000 (masse) x 9.81 (gravity) x 4000 (height) = 39,240,000 Joules = 10.9 kWh.
Now, in water, taking account for Archimedes’ buoyancy. Concrete density: 2.4 tons/m³. 1 ton of concrete is 0.416 m³. The downward hydrostatic force is 1000 - 416 = 584 kgf = 5729 N. The gravity becomes 5729 / 1000 = 5.729. I use again the formula: 1000 (masse) x 5.729 (gravity) x 4000 (height) = 22,916,000 Joules = 6.365 kWh.
Air or water resistance is not taken into account. In practice, even water resistance would be low given the low descent speed, which is stabilized at about 2 m/s.
Now the first video indicates a speed of 8 kmh, so 2.22 m/s, leading (for 1 ton and by kinetic energy) to 1000 x (2.22)² / 2 = 2469 J per second, so 2469 W until stopping. The time with 4000 m height is only 4000/2.22 = 1800 seconds. So 1 ton of concrete falling from 4000 m at stabilized speed of 2.22 m/s in water will produce about 1.2345 kWh, and the double (2.469 kWh) if falling from 8000 m at stabilized speed of 2.22 m/s (calculations to be verified).
The claim of 2x less density for concrete compared to Tesla battery is largely exaggerated, and the number I provide is about 160x less, 200 kWh becoming 1.2345 kWh. But the gravity energy storage in water can be interesting because concrete is cheap (200 $ per ton) and has a long lifespan, unlike chimical batteries.
I propose using sandbags. Sand is still far cheaper (and non-polluting): 25 $ per ton. If it is 200x less efficient than Tesla battery, it would be equivalent to a Tesla battery of 5 kg, so 1 kWh. And a Tesla battery of 1 kWh would be far much more expensive than a ton of sand.
Some calculations with sandbags I propose:
For a sandbag of 320 tons (320,000 kg), diametrical section = 10 m², height = 20 m, volume = 200 m³, sand density = 1,600 kg/m³, the downward hydrostatic force is 120,000 kgf, so 1,177,200 N, the limit velocity is about 21.7 m/s with a drag coefficient of 0.5, and the “gravitational acceleration” (force in N / mass in kg) is only (because of the aquatic environment leading to Archimedes’ buoyancy) 3.67875 m/s² instead of the usual 9.81 m/s². Note: 320 000 (kg) x 3.67875 = 1177200 (N). Falling at 2 m/s, it generates 320 000 x 2²/2 = 0.64 MW until it stops.
The facility is sited adjacent to a wind farm and has a 25 MW / 100 MWh capacity (in other words, the facility can provide 25 MW of electricity to the grid for 4 hours at a time).
The speed seems to be far higher than the 2 m/s for ocean gravity storage (limited speed because of Archimedes’ buoyancy and hydro drag), leading to far higher power density, because kinetic energy increases by the square of the speed.
An interesting critique on the video below:
Hi Pierre: So I guess my math was OK in confirming my suspicion that this company’s claims were exaggerated by more than an order of magnitude, right?
1. Most people would never notice the numbers were false
2_This illustrates how easy it is for these companies to put out false information - nobody even notices - where are the “science editors”? Probably too deskbound to know much of anything about anything, really.
3. As with politicians saying things that everyone knows are false, the question becomes “Are they lying, or are they stupid enough to believe what they just said?”
Thanks for doing your math. By the way, if you want to include water buoyancy. all you have to do is multiply your answer for a dry state. by the ratio of the density pf water over concrete, and subtract that result from the original amount of energy. At least, that’s what my feeble brain is telling me… I just didn’t bother since my instinct tells me the difference is only about 10% or so, and it doesn’t change the story much, especially since you could always add a little more weight