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MIT engineers create an energy-storing supercapacitor from ancient materials

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Re: MIT engineers create an energy-storing supercapacitor from ancient materials

#61

Post by jaclaz »

harvie wrote: post #50

There is usualy steel reinforcement (rebar) in the concrete. Isn't introducing electrical current gonna cause galvanic corrosion of the rebar? Might even affect concrete structures around the capacitor, not just the capacitor itself. Also if i understood correctly, this capacitor would need to be kept wet (with water) to remain operational right? Wet basement is extremely annoying thing with many unpleasant consequen…

If it's not the galvanic effect, it would be more direct corrosion as the block will be "soaked in a standard electrolyte material, such as potassium chloride".

And - given that the concrete will be poured "normally" - the reproducibility of these "power foundations" is likely to be low (and as you say there is no easy wayback).

Besides, concrete is not just water and cement, the various sized aggregates (sand, gravel, finer aggregates) are what make it actually "concrete", the "grain" of concrete used in construction is very different from pure cement+water (and 3% carbon) mix, the samples they made (1 mm thick) won't likely scale up.

Re: MIT engineers create an energy-storing supercapacitor from ancient materials

#62

Post by obiknows »

AstralStorm wrote: post #58
WJW wrote: post #56

While I love the ingenuity of this system, I have some trouble seeing it used as an economically viable energy storage option. According to the article, they would need about 45 m3 to store 10 kwh. At a concrete price of 200-300 $/m3, that would come to 9-13.5k USD just for the concrete. That's omitting any costs for the carbon black electrolyte, material processing, electrolyte separators and other things, so a very…

It might also turn out that lime for the concrete will become a rate limiting material. Not to mention the energy cost involved in mining both it and creating the carbon nanopowder. But, a material with similar hydration properties to concrete, a biopolymer for instance, might exist and be made with less cost... We actually have to start thinking about replacing concrete with something else to be more energy efficien…

hempcrete obviously...

Re: MIT engineers create an energy-storing supercapacitor from ancient materials

#63

Post by RhodesianHunter »

ggm wrote: post #16
RhodesianHunter wrote: post #15

Earlier quoted context omitted.

It isn't. Even with pumping water up hill and letting it flow down, which is far easier and more efficient, there just isn't the land, elevation, and water for the scale we need.

This is one of those sort-of hyperbolic put downs which goes to "we need" encompassing the entire western worlds power requirements. No, you can't replace all existing power sources now and into the future by pumped hydro. Pumped hydro has a massive role to play in power supply, time shifting electricity from renewable sources, providing system resiliency, black start, inductive and inertial load, you-name-it. It als…

No at all. No one is suggesting it must cover all power needs. Sure, there may be municipalities that are advantaged by it due to the unique and perfect nature of their geography. But that's not going to be enough to put any realistic dent in the problem at a national level.

Many people have done the math.

https://dothemath.ucsd.edu/2011/11/pump-up-the-storage/

Re: MIT engineers create an energy-storing supercapacitor from ancient materials

#64

Post by leblancfg »

WJW wrote: post #56

While I love the ingenuity of this system, I have some trouble seeing it used as an economically viable energy storage option. According to the article, they would need about 45 m3 to store 10 kwh. At a concrete price of 200-300 $/m3, that would come to 9-13.5k USD just for the concrete. That's omitting any costs for the carbon black electrolyte, material processing, electrolyte separators and other things, so a very…

Raw concrete price in USA is closer to 150$/m3, often less.

One thing we don’t know is life expectancy vs Li-ion, whose 10-year charge is ~60%.

I haven’t read the paper; one thing that’ll also be interesting is operating temperatures. This could be a massive upside to concrete supercaps in certain parts of the globe.

Re: MIT engineers create an energy-storing supercapacitor from ancient materials

#65

Post by causi »

ipsum2 wrote: post #26
dmvdoug wrote: post #19

Earlier quoted context omitted.

I thought the same thing, so I went and looked at the paper, and unfortunately, the paper itself has some of these kind of speculative claims as well.

Unpopular opinion, most of MIT's research claims are preposterous and can be safely ignored. Their undergraduate education is quite good, but the research output is quite shoddy. The only exception is their computational photography group (Fredo Durand) is pretty legit.

If you Ctrl+F "patent" on an article about a technological breakthrough and get no results you can go ahead and close the window. It's not going to be relevant to your life for at least a decade if ever.

Re: MIT engineers create an energy-storing supercapacitor from ancient materials

#66

Post by nostrademons »

hbossy wrote: post #57
robinzfc wrote: post #29

Earlier quoted context omitted.

To estimate the cost and practicality, assume you build a tower 120 meters tall and machinery able to lift 60 tons block of concrete to the top, then retrieve the stored energy by lowering it to the ground level. Think for a moment how much that would cost. Then calculate: mgh = 60000kg x 120m x 10m/s^2 (assume acceleration of gravity is 10m/s^2 for simplicity, no energy losses due to friction etc). The result is 72…

Or you could avoid building the machinery and just pump water up and down. Then to lower the cost you could drop the tower idea and use a natural hill with reservoir on top. Surprise, surprise you just invented a pumped-storage power station.

Pumped hydro is great, but there are relatively few geographic areas where the terrain is suitable. You need a valley that can be dammed to fill a reservoir, enough water that it actually becomes a reservoir, and then a gentle enough slope coming out of the dam that you can build a secondary reservoir with enough water to capture the outflow of whatever period of time you're storing the energy and pump it back in.

California is one potential location, and there's been a lot of interest in pumped hydro from the California Department of Energy (and utilities), but I doubt it'd work as well nationwide.

Re: MIT engineers create an energy-storing supercapacitor from ancient materials

#67

Post by lofatdairy »

ipsum2 wrote: post #26
dmvdoug wrote: post #19

Earlier quoted context omitted.

I thought the same thing, so I went and looked at the paper, and unfortunately, the paper itself has some of these kind of speculative claims as well.

Unpopular opinion, most of MIT's research claims are preposterous and can be safely ignored. Their undergraduate education is quite good, but the research output is quite shoddy. The only exception is their computational photography group (Fredo Durand) is pretty legit.

MIT's research output is certainly top notch, but the blame for this breathiness is squarely on the institution's communication office and whoever directs them to constantly put out such fluffy pieces. FWIW they're not the only institution with that particular problem, and it clearly does well to boost their prestige with the general public.

Re: MIT engineers create an energy-storing supercapacitor from ancient materials

#68

Post by bazzargh »

robinzfc wrote: post #29
8bitsrule wrote: post #12

Seems to me that the potential of simply lifting a weight up (storage) and down (generation) beats these fancy engineering goals for cost and practicality. Especially if the weight being lifted is a container full of rocks. At first glance there are plenty of those everywhere. No hills or reservoirs needed either. Of course, no papers need to be published ... that may be the goal.

To estimate the cost and practicality, assume you build a tower 120 meters tall and machinery able to lift 60 tons block of concrete to the top, then retrieve the stored energy by lowering it to the ground level. Think for a moment how much that would cost. Then calculate: mgh = 60000kg x 120m x 10m/s^2 (assume acceleration of gravity is 10m/s^2 for simplicity, no energy losses due to friction etc). The result is 72…

I recalled a company doing exactly that design (but 60m high), EnergyVault - I think they also had mineshaft-based projects too. The cranes stack the weights, so there's a lot more than one weight.

Checking their site, I see they currently have a 100MWh storage under construction in china, with a different, boxy-building design. No idea on costs. https://www.energyvault.com/project-cn-rudong

Re: MIT engineers create an energy-storing supercapacitor from ancient materials

#69

Post by JackFr »

FrankyHollywood wrote: post #36
labster wrote: post #13

Typical university press release: this technology can revolutionize our energy grid by storing energy in a building’s foundation, because we powered an LED with some tiny cells we made.

Well it shows potential, they powered something tangible. It's not like a single atom quantum scale phenomenon.

> Well it shows potential

of q^2/2C

Re: MIT engineers create an energy-storing supercapacitor from ancient materials

#70

Post by tambourine_man »

keepamovin wrote: post #54
Tade0 wrote: post #38

Earlier quoted context omitted.

Lighting rods are actually there to discharge without lighting. In any case 10kWh worth of li-ion batteries is about the size of a water cooler tank, so the whole system - bms, inverter and all - is no larger than a water cooler.

Just a heads up, Chrome flags your HN profile homepage as a "Deceptive site" !!

So does Safari
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