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The rise of batteries in six charts

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Re: The rise of batteries in six charts

#151

Post by _aavaa_ »

LUmBULtERA wrote: post #128
epistasis wrote: post #86

Earlier quoted context omitted.

This argument ignores the cost of transmission and distribution, which are higher costs than the generation itself. And as electricity prices are driven down even further, T&D will come to dominate over energy generation costs. Few models account for this, but Christopher Clack made one, and the lowest cost energy path was a small amount of investment in distribution now, paired with massive deployment of solar on ho…

Unless every home is completely off the grid, you’re going to need to pay for most or the majority of that transmission and distribution anyway. Peak winter and summer I also would imagine many or most residential deployments aren’t going to cover their own need, unless they’re incredibly over built with massive batteries. In any case, I should check out your Christopher Clack reference.

As long as the houses are still connected to the grid you will indeed by paying for distribution costs. But I think that you should expect to see transmission savings since you'll have more of the demand met locally.

Re: The rise of batteries in six charts

#152

Post by photochemsyn »

LUmBULtERA wrote: post #51
aresant wrote: post #4

This is all very encouraging and in particular batteries role in solar Two interesting data points to that end 1) The "duck curve" for CA is almost neutral - eg the timing imbalance between peak demand and solar power generation - battery utilization is the most straightforward solution here - https://twitter.com/baker_edmund/status/1750644294673748366 2) There has been a massive decline in rooftop solar applications…

Given the dramatically lower costs of utility-scale solar vs. residential rooftop solar, is it not better at a society level for state policy to incentivize utility over residential solar? Utility-scale battery installations likewise should be much cheaper.

As far as rooftop solar, it makes a big difference if solar PV is built into the design process at the beginning, rather than tacked on as an afterthought. Similarly, a household battery might be as common in the future as a household hot water heater (with a similar footprint, size-wise).

There's also regional variability - cities absolutely require utility-scale solar, just as they require dedicated agricultural land to feed the population, because there's not enough surface area in a city. Rural/suburban areas on the other hand are ideal for integrated rooftop solar.

Re: The rise of batteries in six charts

#153

Post by matthewdgreen »

breischl wrote: post #137
stcredzero wrote: post #112

Earlier quoted context omitted.

I cannot reasonably run lengths of 110v extension cords down the block to charge a car overnight I used to run extension cords out of windows and across the sidewalk to charge a Fiat 500e.

Works if you live in a first-floor, street-facing unit and can reliably park in front of it. Otherwise it can be tough. It's unfortunate that EVs make the most immediate sense in high-density urban settings, but those same settings have lots of people who can't use the simple kinds of charging infrastructure (eg, Level 1/2 chargers).

Cities are going to have to invest in lamppost and curb charging. These already exist. The good news is that with a modest surcharge to the base electricity cost, they will produce a stream of revenue that can be financialized to pay for the install cost (which is basically AC wiring.) The billing needs to be standardized (this is already mostly done with NACS/CCS.) It’s low hanging fruit and will happen within the next few years.

Re: The rise of batteries in six charts

#154

Post by Gibbon1 »

radium3d wrote: post #77
aresant wrote: post #4

This is all very encouraging and in particular batteries role in solar Two interesting data points to that end 1) The "duck curve" for CA is almost neutral - eg the timing imbalance between peak demand and solar power generation - battery utilization is the most straightforward solution here - https://twitter.com/baker_edmund/status/1750644294673748366 2) There has been a massive decline in rooftop solar applications…

It's super cool you can watch California's grid level batteries "breathe" every day here, https://www.caiso.com/TodaysOutlook/Pages/supply.html#sectio... Yesterday we peaked out at 3GW discharging rate, and 4GW charging rate. We are plowing ahead in the transition to utilizing all of our excess solar! We peak at 25GW expected today, so we have a little ways to go but it's incredible how far and how fast they're repla…

The amazing thing is there basically were no batteries three four years ago. And they can supply about 10% of the max power demand already. So it feels like the technologies we need are now good to go on an engineering an accounting basis. And adoption can be quite rapid. We're not saying in 50 years, 25 years, 10 years. We're looking at 5 years.

Re: The rise of batteries in six charts

#155

Post by dgacmu »

usefulcat wrote: post #135
radium3d wrote: post #77

Earlier quoted context omitted.

It's super cool you can watch California's grid level batteries "breathe" every day here, https://www.caiso.com/TodaysOutlook/Pages/supply.html#sectio... Yesterday we peaked out at 3GW discharging rate, and 4GW charging rate. We are plowing ahead in the transition to utilizing all of our excess solar! We peak at 25GW expected today, so we have a little ways to go but it's incredible how far and how fast they're repla…

Kind of unrelated, but I'm wondering why TX uses so much more electricity than CA. Right now (afternoon of 1/26) happens to be a good time to compare: -- Temperatures are mild throughout most of TX (50s and 60s F); temps in CA are similar, perhaps a bit warmer; -- It's roughly mid-day in both places (3PM TX, 1PM CA); -- TX has a population of ~30M, CA has ~39M ..yet somehow right now TX is consuming ~47GW (per ercot)…

It's a mix of a bunch of things. CA is more heating day dominated than TX, and as a result of that, more households use natural gas for heating, whereas you're more likely to see supplemental electric heat in TX than, particularly, NorCal.

(2) high energy costs lead to more investment in electrical efficiency in CA;

(3) high energy costs mean that if you're running an aluminum smelter (for example), you don't run it in CA. Or building a new mega data center. so there are fewer electricity-intensive industrial facilities in CA than there would otherwise be.

Re: The rise of batteries in six charts

#156

Post by earthling8118 »

treflop wrote: post #52
crote wrote: post #44

Earlier quoted context omitted.

We don't have billions of people living in the wilderness. And technology has reached a price level where off-grid solar is actually an affordable and superior alternative to propane and diesel for household use in rural Africa.

Yeah but the article is just about batteries and someone asked to see a graph about energy density. Plus they asked about airplanes and somehow you made it about cars.

The person you are responded to did not make it about cars. They were responding to someone talking about cars

Re: The rise of batteries in six charts

#157

Post by pkolaczk »

api wrote: post #75
tonymet wrote: post #55

Earlier quoted context omitted.

Lithium Battery 0.5 kWh/kg Diesel 12.7 kWh/kg

Diesel is more like 3.175 (25%) due to the inefficiencies of small heat engines. You're throwing away like 3/4 of the energy as waste heat. Electric motors are >95% efficient and lithium batteries are in the high-90s percent efficient. Electricity is already low-entropy, whereas energy from burning petrol is high entropy and thus contains less useful work.

Diesel has efficiency of 40% not 25%.

Re: The rise of batteries in six charts

#158

Post by _aavaa_ »

slingnow wrote: post #105
thelastgallon wrote: post #20

Earlier quoted context omitted.

> I'd like to see the the energy density of petrol for comparison. Petrol's higher energy density doesn't matter as much as people think. Electric vehicles are around four times as efficient as petrol. In a petrol car, only 20% of the energy is converted to motion. In electric cars, this is around 80% (with some variation dependent on regenerative braking). I wrote about this extensively in a previous article: https:…

"Doesn't matter as much as people think" Doesn't matter for WHAT? You start out talking about energy density, and then cite some numbers regarding efficiency. What does one have to do with the other? You've done nothing to support your opening claim here.

"Energy" value of gasoline and "energy" value of a battery pack are measuring two very different things even though they are both units of energy. When you burn gas in an engine, the engine has a theoretical upper limit on its efficiency which is FAR below 100%, and electric vehicle does not. So saying that gasoline has an energy content of 115,000 BTU/gal doesn't mean much since you'll be lucky to see 30% of that be turned into useful work.

Re: The rise of batteries in six charts

#159

Post by 1970-01-01 »

sandworm101 wrote: post #142
1970-01-01 wrote: post #136

Earlier quoted context omitted.

Domestic solar isn't as efficient as solar power plants. If we took this 25% and instead built solar farms, we would be farther ahead. Domestic battery power plants do make sense however.

Yes but a solar panel literally feet from the EV it is charging avoids massive transmission infrastructure.

That doesn't make sense. Very few EV owners will recharge over the length of the day while sitting at home.

Re: The rise of batteries in six charts

#160

Post by nerdbert »

LUmBULtERA wrote: post #128
epistasis wrote: post #86

Earlier quoted context omitted.

This argument ignores the cost of transmission and distribution, which are higher costs than the generation itself. And as electricity prices are driven down even further, T&D will come to dominate over energy generation costs. Few models account for this, but Christopher Clack made one, and the lowest cost energy path was a small amount of investment in distribution now, paired with massive deployment of solar on ho…

Unless every home is completely off the grid, you’re going to need to pay for most or the majority of that transmission and distribution anyway. Peak winter and summer I also would imagine many or most residential deployments aren’t going to cover their own need, unless they’re incredibly over built with massive batteries. In any case, I should check out your Christopher Clack reference.

You don't need as much grid capacity if houses have their own generation and storage.
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