The latest developments in energy storage technology

[Trainee Engineering]

so far, I notice that there are 2 methods to address long-duration blackout here:
1. generate the needed power on and use it day by day
2. generate and store the needed power for the entire 3-week period (in my case, it's 21 days @10kWh, totalling 210 kWh) in one go and store this for the whole year

if possible, I prefer method #2. is there any battery out there with such capacity that's cheap and durable (minimum leakage through long period of time).

 

[sophiecentaur]

in one go

You would need to define what that means. As it stands, it implies a massive Power capability which would be unused for most of the year. Not good value. The cost of a very high spec battery would make it less attractive than using a cheaper (lead acid, for instance) system that's charged up with the cheapest source (overall cost = capital plus energy input) you can get hold of and possibly trickle charged from another source until the time it's actually needed.
But a battery bank that's only used once a year is probably not good value. You could not expect many years of use. Otoh, a second hand diesel generator set would not cost a lot and the fuel could be bought over the year (getting it at the cheapest prices) and stored in a tank. It's not a green solution but does that matter for three weeks of the year. A system like that could last you for decades.

 

[anorlunda]

cheap and durable

It would be far more effective to reduce the energy demands during the blackout period from 10kWh to 1kWh per day. At that level, solar+lead-acid batteries, become much more affordable and practical.

If you can eliminate the AC inverter, it becomes more cheap and durable. LED lighting and device recharging are best done with DC. 12VDC refrigeration systems are very energy effective, cheap, and durable. Propane fueled refrigeration systems are another alternative. There are many ways to pump water without use of electricity.

It becomes more of a social problem than a technical problem. You must convince the people to make do with less. If your goal is to provide during blackouts the same convenience, comfort and cost levels as the power grid provides, you'll fail.

Can you list for us how the 10 kWh/day is being used?

 

[mfb]

A storage system for the full three weeks will cost at least a factor 10 more. You said price is not an issue in post 1, but where is the big disadvantage of on-demand production if it saves more than $50,000?

Reducing electricity consumption will help in both cases, of course.

 

[Trainee Engineering]

You would need to define what that means. As it stands, it implies a massive Power capability which would be unused for most of the year. Not good value. The cost of a very high spec battery would make it less attractive than using a cheaper (lead acid, for instance) system that's charged up with the cheapest source (overall cost = capital plus energy input) you can get hold of and possibly trickle charged from another source until the time it's actually needed.
But a battery bank that's only used once a year is probably not good value. You could not expect many years of use. Otoh, a second hand diesel generator set would not cost a lot and the fuel could be bought over the year (getting it at the cheapest prices) and stored in a tank. It's not a green solution but does that matter for three weeks of the year. A system like that could last you for decades.

in one go means I store all the energy (210 kWh) now to be used next year. but in one go may mean I collect the energy in a week, or in a month, no problem. it just means that I don't need to store up energy for a day, and then consume all the next day, and keep repeating that cycle everyday.
btw, when it's flooding, the water doesn't really move. we just wait till it recedes, and the river is quite far away from my residence complex. like this one

It would be far more effective to reduce the energy demands during the blackout period from 10kWh to 1kWh per day. At that level, solar+lead-acid batteries, become much more affordable and practical.

If you can eliminate the AC inverter, it becomes more cheap and durable. LED lighting and device recharging are best done with DC. 12VDC refrigeration systems are very energy effective, cheap, and durable. Propane fueled refrigeration systems are another alternative. There are many ways to pump water without use of electricity.

It becomes more of a social problem than a technical problem. You must convince the people to make do with less. If your goal is to provide during blackouts the same convenience, comfort and cost levels as the power grid provides, you'll fail.

Can you list for us how the 10 kWh/day is being used?

1.5 kWh --> fridge
2 kWh --> AC
2 kWh --> rice cooker, 2 TVs, LED bulbs
1.5 kWh --> PC whole day
3 kWh --> spare, just in case. so basically, 8 kWh should be enough.
ideally, I'd prefer not change any lifestyle, even during blackout, but if it's not possible, then will resort to "graceful degradation", meaning, sacrifice the least needed ones. the listing above is already sorted based on importance, top being most important, bottom least important.

A storage system for the full three weeks will cost at least a factor 10 more. You said price is not an issue in post 1, but where is the big disadvantage of on-demand production if it saves more than $50,000?

Reducing electricity consumption will help in both cases, of course.

I'm not against on-demand production, but as someone said (forgot where exactly in these posts), solar power only brings misery, and my alternative is methane or gasoline generator, which also needs to be refilled everyday, and when it's flooding, not sure if that's going to work

 

[rbelli1]

when it's flooding, not sure if that's going to work

If you don't have a flood safe place to store a generator and three weeks of fuel you will certainly not have a place to store three weeks worth of batteries.

For 8kWh per day for three weeks you need about 250 liters of batteries.
https://en.wikipedia.org/wiki/Lithium-ion_battery

You need only about 60 liters of diesel.
https://en.wikipedia.org/wiki/Diesel_generator

The converter for both systems will be of a similar size magnitude.

Another benefit of a generator is that you will be able to find someone to repair it with little or no trouble. You can learn basic maintenance yourself in a few hours.

Is seems to me if you are willing to spend a large sum of money on a backup system you could go the generator route and outfit your entire apartment complex and provide operating costs for many years with the same amount of money.

BoB

 

[Rive]

so far, I notice that there are 2 methods to address long-duration blackout here:
1. generate the needed power on and use it day by day
2. generate and store the needed power for the entire 3-week period (in my case, it's 21 days @10kWh, totalling 210 kWh) in one go and store this for the whole year

if possible, I prefer method #2. is there any battery out there with such capacity that's cheap and durable (minimum leakage through long period of time).

With stored 200+kWh you will sit on the very top of a veeeeeryyyyy water sensitive bomb. Do you really want that? During a flood?
The grid is down exactly to prevent such situations. But with such scale battery backup, it's worse than it would be with the grid on...

I suggest to build a limited capacity battery backup, which can provide adequate power for limited usage for 1-2 days: and back it up with some generator.
The limited battery backup can be built safely.
The fuel is not that flood sensitive.
The battery alone can handle 90% of the daily load.
The generator can recharge the battery fast.
The battery and the generator together can handle the rest of the load.

This way it is a classic, widely used system: esy to build, handle and repair.

 

[jim hardy]

i grew up in hurricane territory, South Florida. Onsite generators became affordable to average folks only around the 1980's . One learns to get by without central airconditioning , and in S Fla you can get by without hot water because it comes out of the ground seventy something F.
So a couple KW gas generator will do just fine for a fridge and lights.
A Coleman gasoline campstove got us by for two weeks after Andrew (1992) , i had no generator.
After Hurricane Irene friends loaned me a 4 kw generator and i considered it a luxury for it'd start a one room "windowshaker" airconditioner that even drowned out the generator noise so we could sleep comfortably on 90 degF nights. I was without electricity for 3 weeks.
What you miss most is refrigeration. I'd get a propane fridge from a RV place for the garage, and a small generator to keep the freezer cold. Harbor Freight sells a 800 watt two stroke for 88 bucks when on sale.

Back to topic of energy storage

Did anybody watch NOVA this week ? Some guy has solved the pyrotechnics problem with lithium batteries. He uses a permeable plastic between the plates, in the Nova show he drives nails through it with no ill effect.
http://www.pbs.org/wgbh/nova/tech/super-battery.html
old jim

 

[sophiecentaur]

I'd get a propane fridge from a RV place

The Waeco (and others) 12V compressor fridges are 'real' fridges and are very economical on current - averaging only around an Amp. I have a small one (really tiny) that will deep freeze its contents to -18C. It would be worth doing the sums to try to include this in any electrical power budget. Propane has its place, of course, when the electrical supply won't support even that low level of power.

 

[jim hardy]

The Waeco (and others) 12V compressor fridges are 'real' fridges and are very economical on current - averaging only around an Amp. I have a small one (really tiny) that will deep freeze its contents to -18C. It would be worth doing the sums to try to include this in any electrical power budget. Propane has its place, of course, when the electrical supply won't support even that low level of power.

Certainly that's good sensible advice. 12 volt appliances are becoming more available, too.

I think nowadays DIY'ers could add a 12 volt system to their house, a few LED lights in every room and an inverter big enough to carry the fridge via extension cord.
An automobile alternator , lawnmower engine , and "utility battery" like used in riding lawnmowers is the 'poor man's' answer. I plan to do that in my guest house.

I have a gas kitchen stove because electricity can go out. It was sure nice after Hurricane Irene to have hot coffee, i invited neighbors over next morning. Wind was still over 40 mph but we thanked our lucky stars it went west of us.. old jim

 

[OCR]

Did anybody watch NOVA this week ? Some guy has solved the pyrotechnics problem with lithium batteries.

Yeah, I saw that....

 

[Trainee Engineering]

ok, another question. I take it Tesla's Powerwall is currently the most advanced phase in energy storage tech? we can only manage to store 14 kWh worth of energy in such a huge space? and it's still very expensive too.
so, if we use the analogy of data storage, we're still in floppy disk era where we can only store 1.44MB worth of data, not yet in CD/DVD era where we could store hundreds of MB, let alone flashdisk era where we can already store gigabytes worth of data in a very small package. is this analogy describe current phase in energy storage technology?

 

[sophiecentaur]

Certainly that's good sensible advice.
old jim

I have the seal of approval so I'll continue. The bare refrigeration units are available for self fitting into boats etc. and you can make the enclosure as thermally efficient as you like, unlike a ready made fridge. You can keep the mean consumption very low if you use thick enough insulation and use a 'chest' design with a thick lid. The biggest demand is when you put a new item in that's not already cold (or if you actually try to freeze down stuff). They're blissfully quiet runners, too and you can put the external condenser a good distance away from the unit. A bit on the pricey side but it does what it says on the tin.

 

[sophiecentaur]

flashdisk era where we can already store gigabytes worth of data

1TB on a USB stick is available in my local shop. Where will it all end?

 

[Trainee Engineering]

1TB on a USB stick is available in my local shop. Where will it all end?

yeah, I mean, we're still at 14kWh in 44 in × 29 in × 5.5 in package, so if I want to store 210 kWh, it will take 15 units which will take a lot of space.

 

[mfb]

Packing data better is much easier than increasing energy density. As analogy, replace a single rock by many small pebbles: you increased the number of objects (data), but you didn't increase the total mass (stored energy).

Batteries have a low energy density compared to chemical storage systems (like fuel for the generator). They are also more dangerous in connection with water.

 

[mheslep]

... if we use the analogy of data storage, ...

Not a good idea. The advances in information technology involved storing a fundamental unit of information (on/off) in ever smaller physical structures. Much of IT hardware engineering became exercises in managing complexity, i.e. how does one quickly carve 10 million transistors into a square mm, control all their interactions, and have them finally act as a useful macro level device. Energy storage has few if any parallels.

 

[jim hardy]

I take it Tesla's Powerwall is currently the most advanced phase in energy storage tech? ...
so, if we use the analogy of data storage, we're still in floppy disk era where we can only store 1.44MB worth of data, ...
is this analogy describe current phase in energy storage technology?

Energy and data are not alike.
Energy in quantity will hurt you.

I am skittish whenever:
in high places (gravitational potential energy)
going fast (kinetic)
in airplanes (both of above)
around high speed machinery(mechanical)
around high pressure steam(thermal)
around dynamite(concentrated chemical energy, ) in 1960's we kids could buy it in rural hardware stores, and did , but i learned to respect its capability
around electrical sources capable of high current (because copper vapor follows same gas laws as dynamite vapor)so i think your analogy

yeah, I mean, we're still at 14kWh in 44 in × 29 in × 5.5 in package, so if I want to store 210 kWh, it will take 15 units which will take a lot of space.

is more in tune with steam power ca 1830
when to make ten horsepower took a reciprocating engine weighing many stones and a riveted firetube boiler prone to explode destroying the building and cooking its occupants.
http://www.hevac-heritage.org/electronic_books/boiler_explosions/1-BOILER_EXPLOSIONS_IN_PICTURES.pdf

I'm just not ready yet to admit big lithium batteries into my life.

Boeing was too stubborn to face that with 777 ..

mfb and mhselep have it right.

old jim

 

[NTL2009]

I recall seeing an estimate somewhere, of just how far a lithium battery could advance. It was beyond my feeble knowledge of chemistry, but they were able to estimate just how dense you could go with lithium, if you assumed you could magically avoid all the real world limitations. IIRC it was between one and two orders of magnitude. And then the real world intervenes.

Anyone here know of a source, or able to take a stab at it?

 

[discountbrain]

Hi all,

I'm interested in the latest development in battery technology. as of now, from what I understand, the most advanced tech in energy storage (battery) is created by Tesla, the PowerWall. but, even that, can only store 14kWh per unit. my house consumption is about 10kWh per day. my question is, what are the type of batteries out there available to the public? I'm only concerned of these things:
1. capacity --> I need to store 2-3 weeks worth of energy (in case of blackouts), so, it's somewhere around 140kWh - 210 kWh. if possible, I need it to be less than 10 units (so each unit is around 21kWh)
2. durability --> must be able to store huge amount of energy for a long period of time without dissipating. Now, it won't be charged and discharging frequently. charged only after a blackout, and won't be discharging until the next blackout, so storing for long time
3. warranty --> if possible, above 10 years warranty that energy leakage is less than 5%

price is not an issue. what are my options?
what's the latest type of battery suited for this type of usage?

thanks

I just learned Eos Energy is planning to sell their rechargeable zinc/air batteries to the consumer in 2017. I'm calling them tomorrow to see when I can get some. They have been selling them to utilities for a while now. Zinc is quite inexpensive, these batteries can be cycled over 5k (maybe 10k) times, they store 3 TIMES the energy of Li-ion batteries. Look at their website; they are many times superior. I think I'll buy Solar World solar panels. They are made in the USA and some of the most efficient ones there are. This year will be the year I go off grid. I will install this myself-I think installers might think they can rip u off. I will buy a transfer switch and get a certified electrician to install it. This will be so I will still be attached to the grid while makings sure everything is working OK. Transfer switches are not uncommon. They are for when someone has their own generator hooked up to their system.

 

[discountbrain]

Someone here mentioned the cost of solar vs the grid. Somewhere else people were quoting what it cost to get the power company to hook u up with electric. They were giving figures like $10k! I found that hard to believe. It might be pretty expensive though if u lived more than 1/2 mi from existing power.

 

[mheslep]

store 3 TIMES the energy of Li-ion batteries

One problem with metal air batteries has always been that their *power* density is dozens of times lower than a traditional electrolyte battery. Diffusing oxygen into the metal tends to happen at a much lower rate than ions diffuse in li-ion, especially when nitrogen and water vapor get in the way. So, it's long been possible to buy non rechargeable metal air batteries with greater *energy density* than li-ion, but to obtain the same power required infeasible parallel banks of metal air.

 

[mfb]

Eos energy expects $160/kWh for a large-scale project. For 210 kWh that is still $35,000 worth of batteries.

The power density would be fine for a 3 week storage. Typical values are 500 Wh/kg and 100 W/kg, discharge times longer than 10 hours will work without problems.

 

[anorlunda]

In our enthusiasm about technologies, everyone seems to be ignoring @jim hardy 's safety warning in #68.

210 kWh = 765 megajoules = 0.18 tons of TNT = 163 kg of TNT. A short circuit could release that energy in a very short time. It is utter foolishness to think of storing that much energy in a residence. (not to mention a residence subject to flooding)

If we want to discuss living off the grid with solar plus batteries, that's OK (edit: then start a new thread). Storing 2-3 weeks of electric energy is very different and very dangerous.

 

[DrClaude]

Closed pending moderation.

 

[berkeman]

If we want to discuss living off the grid with solar plus batteries, that's OK (edit: then start a new thread). Storing 2-3 weeks of electric energy is very different and very dangerous.

Thread will remain closed with that reminder about safety.