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Falling lithium-ion battery prices to drive rapid storage uptake

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Re: Falling lithium-ion battery prices to drive rapid storage uptake

#31

Post by skummetmaelk »

merpnderp wrote: post #3
nabla9 wrote: post #2

$200/kWh by 2019. Assuming that households consume between 30 kWh and 15 kWh electricity daily on average and you want to have storage capacity for 1/3 of daily electricity consumption to get wind or solar energy work, you need 10-5 kWh per household. That's $2000 - $1000 per household. If that battery lasts 10 years, its $200 - $100 per year. It's workable and scales if we are able to reuse lithium. When does that h…

That wouldn't work for much of the South where summer usage for a house can easily hit 100 kWh/day for air conditioning. The hottest part of the day usually starts at about the end of the prime solar hours. Plus you'll want massive overcapacity of your batteries as deep discharges drastically reduce their useful lifespan.

100 kWh/day is just incredible. The average consumption per person in the nordics is about 1500 kWh per YEAR.

Re: Falling lithium-ion battery prices to drive rapid storage uptake

#32

Post by yourapostasy »

cobookman wrote: post #15
zAy0LfpBZLC8mAC wrote: post #11

Earlier quoted context omitted.

I would think that for that use case, using thermal storage should be more efficient? Don't store electricity to run AC later, but run AC to cool down water or the ground beneath your house or something, and then cool your house with that later.

Or build something like an Earthship ( http://earthship.com/ ). I know that these can air condition a house in New Mexico through geothermal heat transfer, however no idea how they handle the more humid summers of the South East.

They work, but aren't as comfortable as in drier climes. Humidity is tough to control with low-energy, low-maintenance solutions. Unfortunately, many people's discomfort perceptions are heavily influenced by humidity.

Re: Falling lithium-ion battery prices to drive rapid storage uptake

#33

Post by rch »

EngineerBetter wrote: post #14
merpnderp wrote: post #3

Earlier quoted context omitted.

That wouldn't work for much of the South where summer usage for a house can easily hit 100 kWh/day for air conditioning. The hottest part of the day usually starts at about the end of the prime solar hours. Plus you'll want massive overcapacity of your batteries as deep discharges drastically reduce their useful lifespan.

Wow - that's a crazy amount of energy. As a Brit who's never been the south of the US, is that figure really true? 100kWh is about 300 miles in a Tesla, or boiling a kettle constantly for about 30 hours. If that's really accurate, then I'm staggered at how much energy folks must be using to keep cool, and makes my efforts at saving energy seem paltry in comparison.

Texas also produces the most wind power of any U.S. state.

https://en.wikipedia.org/wiki/Wind_power_in_Texas

The source in wikipedia is out of date, but it's still true as of Q3 2016:

http://www.awea.org/Resources/Content.aspx?ItemNumber=9488

Re: Falling lithium-ion battery prices to drive rapid storage uptake

#34

Post by CyberDildonics »

barrkel wrote: post #8
toomuchtodo wrote: post #5

Earlier quoted context omitted.

> When does that happen? Soon. https://electrek.co/2015/08/16/the-power-of-controllable-cha... https://i.imgur.com/oLBNeW4.png

I couldn't find the information about reusing lithium on those links?

Are you asking if you couldn't find it?

Re: Falling lithium-ion battery prices to drive rapid storage uptake

#35

Post by ChuckMcM »

I wonder how much of this is simply the Gigafactory coming online at full production + others trying to keep their factories running.

If you look at Tesla's plan to be making 10,000 model 3's a week, with a nominal 90 kWh battery in each that is 900 MWh a week of capacity or 46 GWh capacity a year. But it is all tied up in cars of course[1].

The power companies have been screwing around with rate plans to keep grid-tied solar from being as economic as it could be and so I do see a lot of people such as myself moving to a whole house storage system at some point.

[1] I fully expect a TV show to have a scene where they need more power and the 'genius' hero looks out the window and sees a row of electric cars charging and "hacks the system to feed the car's energy into the power grid for the extra energy needed to save the day" along with the gratuitous cars exploding as they are being drained too quickly but reaching the minimum level of power at just the right time to save the world.

Re: Falling lithium-ion battery prices to drive rapid storage uptake

#36

Post by ptero »

epistasis wrote: post #25
ptero wrote: post #18

Earlier quoted context omitted.

Maximum discharge speed (which is one of the very few storage characteristics I can think of to be measured in GW) is pretty much irrelevant for storage systems. Add a few quick discharge capacitors that cost almost nothing and boom -- your max discharge speed shoots through the roof (but speed goes down for a very short time). Maybe sustained charge speed is a (little bit) more meaningful thing you can express in GB…

Your instincts would be wrong on this one. This is a technical article, that talks about all the right things for grid storage: value stacking, $/kWh (note the h), various install locations such as behind-the-meter, etc. They know what they are talking about. Currently, grid discussions happen mostly in the MW or GW space. Maximum instantaneous discharge speed is pretty much the most important characteristic for stor…

OK, thank you, good to know. I will re-read with this in mind to give this a fresh look.

Re: Falling lithium-ion battery prices to drive rapid storage uptake

#37

Post by yourapostasy »

EngineerBetter wrote: post #14
merpnderp wrote: post #3

Earlier quoted context omitted.

That wouldn't work for much of the South where summer usage for a house can easily hit 100 kWh/day for air conditioning. The hottest part of the day usually starts at about the end of the prime solar hours. Plus you'll want massive overcapacity of your batteries as deep discharges drastically reduce their useful lifespan.

Wow - that's a crazy amount of energy. As a Brit who's never been the south of the US, is that figure really true? 100kWh is about 300 miles in a Tesla, or boiling a kettle constantly for about 30 hours. If that's really accurate, then I'm staggered at how much energy folks must be using to keep cool, and makes my efforts at saving energy seem paltry in comparison.

In the US, there are very large variations in house interior volume, insulation, and usage patterns. Upper-middle class house built on a slab with standard in Dallas with a stay-at-home mom, for example? I wouldn't bat an eyelash at 100kWh/day on the hottest and wettest days. Condo apartment in downtown Houston? That would be excessive.

US insulation requirements in Dallas is R-20 in the walls [1]. The PassivHaus standard is R-40 to R-60. I believe Germany requires R-5 at a minimum. Mainstream US construction design and practice still doesn't account for thermal bridging, so that defeats much of the insulation we're throwing into our buildings.

[1] https://eepartnership.org/wp-content/uploads/2016/02/Texas-2...

Re: Falling lithium-ion battery prices to drive rapid storage uptake

#38

Post by comicjk »

Using lithium-ion batteries for stationary storage is interesting because their original advantage was all about light weight (lithium is the lightest metal element).

Now, it seems the development effort devoted to lithium-ion has paid off so well that they are the best OVERALL battery solution. The single-minded effort we put into cell phones and cars is so strong that it now reaches all the way to homes and the grid.

To me, this suggests that all sorts of cool technologies might be possible if we as a society could concentrate on making them work.

Re: Falling lithium-ion battery prices to drive rapid storage uptake

#39

Post by derefr »

Hah, I misinterpreted "storage" here, and thought this was going to be about Li-ion cells getting cheap enough to replace the capacitors in the Power Loss Protection circuits in hard drives/SSDs/NVMe boards.

Which doesn't make sense, after giving it a second's thought—batteries wear out after just a few years, while capacitors (very nearly) don't, so it'd put a hard lifetime on drives. (Though, for server use-cases with constant workloads, they have hard lifetimes anyway...)

But it's an interesting question! If—rather than UPSes as specialized enterprise-level hardware—we instead had Li-ion cells on computer motherboards (picture a big brother to the CR-2032 CMOS battery) that kept the disks alive for up to, say, 30 minutes after power loss—could we architect our storage subsystems differently?

(Sorry if that's a complete tangent from the topic at hand, but I'm not sure where I'd post this otherwise!)

Re: Falling lithium-ion battery prices to drive rapid storage uptake

#40

Post by baybal2 »

ChuckMcM wrote: post #35

I wonder how much of this is simply the Gigafactory coming online at full production + others trying to keep their factories running. If you look at Tesla's plan to be making 10,000 model 3's a week, with a nominal 90 kWh battery in each that is 900 MWh a week of capacity or 46 GWh capacity a year. But it is all tied up in cars of course[1]. The power companies have been screwing around with rate plans to keep grid-t…

>I wonder how much of this is simply the Gigafactory coming online at full production + others trying to keep their factories running.

The "Gigafactory," is a drop in the ocean if you count noname Chinese factories, but it will be one of the biggest market players outside of China

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