5 ms·

Solar panels are getting cheaper by the day. Solar power is not. Because between the panel and the lightbulb lies a battery.

jaggederest 2y ago
Do you think batteries are getting more expensive over time?
- XorNot 2y ago
  I think the assumption they would get cheaper given a massive change in their adoption patterns is unfounded. We know that lithium prices have gone up from the rise in EVs, and this has in part driven Tesla to switch to LiFePO4's rather then Li-Ion packs in some of their cars. Same effect with coltan. (although lithium is declining currently because EV sales in China have slowed). What would be the effect of the demand for terawatt-hour levels of batteries? Even if lithium is replaced with sodium in the application, the manufacturing capacity isn't there and won't be for quite some time - and the higher-value applications will get first take (i.e. EVs). Even if the lithium demand was saturated battery wise, at the steady state point the cost can then simply stabilize around the refurbisment/recycling cost of lithium/sodium/whatever from batteries. Sigmoidal adoption curves look exponential at the start, linear in the middle,and then become asymptotically flat.
  - kragen 2y ago
    > although lithium is declining currently because EV sales in China have slowed have they? 'one in three' of all new vehicle registrations in china were electric last year https://www.iea.org/reports/global-ev-outlook-2024/trends-in-electric-cars https://www.iea.org/reports/global-ev-outlook-2024/trends-in... or 37% https://autovista24.autovistagroup.com/news/ev-registrations-in-china-nearly-double-from-2023/ https://autovista24.autovistagroup.com/news/ev-registrations... and the absolute number seems to be doubling this year, though they only expect a 45% market share these figures do include both hybrids and pure battery models, though in general the 'experience curve' says that things get exponentially cheaper as you produce exponentially more of them
    - XorNot 2y ago
      The experience curve is asymptotic[1]. What do we get if we look at say, FLOPS per US $ over time? This[2]. There is no reason to think batteries are any different, the only margin you have is to argue over which part of the curve you think we're in. A sigmoid curve[3]. [1] https://www.extension.iastate.edu/agdm/wholefarm/html/c5-208.html https://www.extension.iastate.edu/agdm/wholefarm/html/c5-208... [2] https://www.researchgate.net/figure/Number-of-flops-per-United-States-dollar-by-year-Almost-mirroring-the-change-in-computer_fig3_367400092 https://www.researchgate.net/figure/Number-of-flops-per-Unit... [3] https://en.wikipedia.org/wiki/Sigmoid_function https://en.wikipedia.org/wiki/Sigmoid_function
      - jaggederest 2y ago
        That FLOPS graph is an exponential scale... so that straight line "after the sigmoid" is an exponential growth curve. I'm not sure it makes the point you're trying to make.
bruce511 2y ago
Yes, and no. Yes, a lot of people who install residential solar have a battery, and "common wisdom" tends to size the battery up if the solar install is larger. But nothing stops the battery being really small, or indeed (like commercial solar generation) there being no battery at all. Yes, of course, solar is not 24 hours. But having cheap energy "only" half the day (1) is a major plus. And as energy cost fluctuates, so do habits. For example since we got solar we tend to use the dishwasher in the mid morning instead of at night. (1) actual solar availability depends on the width of your country. For example solar plants in say Arizona happily generate good power while the East coast is dark, and panels in say Florida would cater for mornings in California. And that's before we factor in wind, which is commonly stronger in the late afternoon into the evening.
- kragen 2y ago
  you may want to \ your *s never mind, you fixed it
- toenail 2y ago
  > And as energy cost fluctuates, so do habits You're advocating for reverting back to pre electrified times, this stuff is straight from the 19th century. Using energy is good, it is progress.
  - bruce511 2y ago
    Not at all. I'm saying that people adapt very quickly when costs are involved. I'm not saying we sit in the dark at night. I'm saying that we time-shift some energy consumption because some of the day energy is free, and some of the day we pay for it. The pool pump runs during the day. As does the hot water cylinder. The electrical cost for these us now zero (on most days.) Our night-time electricity usage has gone down because it's more expensive. When energy costs the same all 24 hours then it's not something I take into consideration. When it's different habits change. I don't use less energy, if anything I use more. But I factor time-of-day into -when- I use it. Not everything can be shifted. Our peak usage is still in the morning and evening. But scheduled things have moved from night to day.
bryanlarsen 2y ago
Battery prices have dropped 50% in the last 12 months. https://www.pv-magazine.com/2024/03/07/battery-prices-collapsing-grid-tied-energy-storage-expanding/ https://www.pv-magazine.com/2024/03/07/battery-prices-collap...
- FredPret 2y ago
  That’s great. Grid-scale battery storage is still a terrible idea when you can simply build a nuke station that does the same job with 0.01% of the waste material and space used.
  - kragen 2y ago
    it seems implausible that a nuclear power plant occupies 0.01% of the space of a battery bank of the same peak power capacity; if anything, i'd suspect the discrepancy is closer to the other way around (edit: it is, see the comment below where i do the math, and please stop posting thoughtless bullshit) if you were talking about the solar farm, then yeah, i'd agree
    - zeofig 2y ago
      If that seems implausible you might want to replause your seemometer. A nuclear plant has much higher energy density than any battery.
      - kragen 2y ago
        well, nuclear fuel rods certainly have much higher energy density than any battery. but they're only a small piece of the power plant, and i wasn't talking about the energy density (joules per liter) but the power density (watts per liter or, since we're talking about land use, watts per square meter) a 10c 2000 milliamp hour 18650 cell produces 20 amps at nominally 3.7 volts, which is 74 watts. if it occupies 18 mm × 18 mm × 65 mm that's 3500 watts per liter. tepco's kashiwazaki-kariwa nuclear power plant is 8 gigawatts, which is 2300 cubic meters of 18650s. if you stack them two meters high, that's 1100 square meters, an area 34 meters square. maybe you have to double that so you can drive a forklift in between the racks of batteries, plus you need some space for things like fireproof bulkheads, wiring, and inverters, but we're talking about maybe 50 meters by 50 meters, 0.0025km². kashiwazaki-kariwa is 4.2km², 1600 times bigger. (also, it's more than two meters tall.) the hypothetical 8-gigawatt battery bank uses 0.06% of the land area. even if you scale up the discharge time from 6 minutes to the usual 4 hours, it's still only 2.4% of the area of the nuclear plant you can get better batteries than that, too. and if you're worried about land consumption, as you have to be in japan, you can put your batteries in a building with multiple floors
kragen 2y ago
solar power is getting cheaper by the day; https://www.pv-magazine.com/2024/04/19/europes-renewable-ppa-prices-fell-5-in-q1/ https://www.pv-magazine.com/2024/04/19/europes-renewable-ppa... says: > Energy consultancy LevelTen says that solar power purchase agreement (PPA) prices fell 5.9% in the first quarter of 2024, with decreases recorded in all analyzed countries except for Romania. It attributes the decline to lower wholesale electricity prices and a fall in solar module prices however, they haven't yet recovered to the 02020 levels, presumably because the astounding precipitous fall in module prices over the last year hasn't been priced in yet
huijzer 2y ago
Batteries are getting cheaper by the day too. Price per kWh halved in China in the last 2 years according to BloombergNEF (https://x.com/colinmckerrache/status/1800901575214514475 https://x.com/colinmckerrache/status/1800901575214514475).
fuzzfactor 2y ago
>Solar power is not. Often there is no battery, but regardless when solar cost goes up it could be due to expensive contractors in-between the panels and the installation & maintenance, before the lightbulb even gets a chance to see a single watt.
- kragen 2y ago
  a major reason in the usa is the tariff regime that has basically completely shut out chinese solar panels from the market; this makes solar panels in the us cost about twice as much as in the rest of the world

jaggederest 2y ago

Do you think batteries are getting more expensive over time?

XorNot 2y ago
I think the assumption they would get cheaper given a massive change in their adoption patterns is unfounded. We know that lithium prices have gone up from the rise in EVs, and this has in part driven Tesla to switch to LiFePO4's rather then Li-Ion packs in some of their cars. Same effect with coltan. (although lithium is declining currently because EV sales in China have slowed). What would be the effect of the demand for terawatt-hour levels of batteries? Even if lithium is replaced with sodium in the application, the manufacturing capacity isn't there and won't be for quite some time - and the higher-value applications will get first take (i.e. EVs). Even if the lithium demand was saturated battery wise, at the steady state point the cost can then simply stabilize around the refurbisment/recycling cost of lithium/sodium/whatever from batteries. Sigmoidal adoption curves look exponential at the start, linear in the middle,and then become asymptotically flat.
- kragen 2y ago
  > although lithium is declining currently because EV sales in China have slowed have they? 'one in three' of all new vehicle registrations in china were electric last year https://www.iea.org/reports/global-ev-outlook-2024/trends-in-electric-cars https://www.iea.org/reports/global-ev-outlook-2024/trends-in... or 37% https://autovista24.autovistagroup.com/news/ev-registrations-in-china-nearly-double-from-2023/ https://autovista24.autovistagroup.com/news/ev-registrations... and the absolute number seems to be doubling this year, though they only expect a 45% market share these figures do include both hybrids and pure battery models, though in general the 'experience curve' says that things get exponentially cheaper as you produce exponentially more of them
  - XorNot 2y ago
    The experience curve is asymptotic[1]. What do we get if we look at say, FLOPS per US $ over time? This[2]. There is no reason to think batteries are any different, the only margin you have is to argue over which part of the curve you think we're in. A sigmoid curve[3]. [1] https://www.extension.iastate.edu/agdm/wholefarm/html/c5-208.html https://www.extension.iastate.edu/agdm/wholefarm/html/c5-208... [2] https://www.researchgate.net/figure/Number-of-flops-per-United-States-dollar-by-year-Almost-mirroring-the-change-in-computer_fig3_367400092 https://www.researchgate.net/figure/Number-of-flops-per-Unit... [3] https://en.wikipedia.org/wiki/Sigmoid_function https://en.wikipedia.org/wiki/Sigmoid_function
    - jaggederest 2y ago
      That FLOPS graph is an exponential scale... so that straight line "after the sigmoid" is an exponential growth curve. I'm not sure it makes the point you're trying to make.

bruce511 2y ago

Yes, and no. Yes, a lot of people who install residential solar have a battery, and "common wisdom" tends to size the battery up if the solar install is larger. But nothing stops the battery being really small, or indeed (like commercial solar generation) there being no battery at all. Yes, of course, solar is not 24 hours. But having cheap energy "only" half the day (1) is a major plus. And as energy cost fluctuates, so do habits. For example since we got solar we tend to use the dishwasher in the mid morning instead of at night. (1) actual solar availability depends on the width of your country. For example solar plants in say Arizona happily generate good power while the East coast is dark, and panels in say Florida would cater for mornings in California. And that's before we factor in wind, which is commonly stronger in the late afternoon into the evening.

kragen 2y ago
you may want to \ your *s never mind, you fixed it
toenail 2y ago
> And as energy cost fluctuates, so do habits You're advocating for reverting back to pre electrified times, this stuff is straight from the 19th century. Using energy is good, it is progress.
- bruce511 2y ago
  Not at all. I'm saying that people adapt very quickly when costs are involved. I'm not saying we sit in the dark at night. I'm saying that we time-shift some energy consumption because some of the day energy is free, and some of the day we pay for it. The pool pump runs during the day. As does the hot water cylinder. The electrical cost for these us now zero (on most days.) Our night-time electricity usage has gone down because it's more expensive. When energy costs the same all 24 hours then it's not something I take into consideration. When it's different habits change. I don't use less energy, if anything I use more. But I factor time-of-day into -when- I use it. Not everything can be shifted. Our peak usage is still in the morning and evening. But scheduled things have moved from night to day.

bryanlarsen 2y ago

Battery prices have dropped 50% in the last 12 months. https://www.pv-magazine.com/2024/03/07/battery-prices-collapsing-grid-tied-energy-storage-expanding/ https://www.pv-magazine.com/2024/03/07/battery-prices-collap...

FredPret 2y ago
That’s great. Grid-scale battery storage is still a terrible idea when you can simply build a nuke station that does the same job with 0.01% of the waste material and space used.
- kragen 2y ago
  it seems implausible that a nuclear power plant occupies 0.01% of the space of a battery bank of the same peak power capacity; if anything, i'd suspect the discrepancy is closer to the other way around (edit: it is, see the comment below where i do the math, and please stop posting thoughtless bullshit) if you were talking about the solar farm, then yeah, i'd agree
  - zeofig 2y ago
    If that seems implausible you might want to replause your seemometer. A nuclear plant has much higher energy density than any battery.
    - kragen 2y ago
      well, nuclear fuel rods certainly have much higher energy density than any battery. but they're only a small piece of the power plant, and i wasn't talking about the energy density (joules per liter) but the power density (watts per liter or, since we're talking about land use, watts per square meter) a 10c 2000 milliamp hour 18650 cell produces 20 amps at nominally 3.7 volts, which is 74 watts. if it occupies 18 mm × 18 mm × 65 mm that's 3500 watts per liter. tepco's kashiwazaki-kariwa nuclear power plant is 8 gigawatts, which is 2300 cubic meters of 18650s. if you stack them two meters high, that's 1100 square meters, an area 34 meters square. maybe you have to double that so you can drive a forklift in between the racks of batteries, plus you need some space for things like fireproof bulkheads, wiring, and inverters, but we're talking about maybe 50 meters by 50 meters, 0.0025km². kashiwazaki-kariwa is 4.2km², 1600 times bigger. (also, it's more than two meters tall.) the hypothetical 8-gigawatt battery bank uses 0.06% of the land area. even if you scale up the discharge time from 6 minutes to the usual 4 hours, it's still only 2.4% of the area of the nuclear plant you can get better batteries than that, too. and if you're worried about land consumption, as you have to be in japan, you can put your batteries in a building with multiple floors

kragen 2y ago

solar power is getting cheaper by the day; https://www.pv-magazine.com/2024/04/19/europes-renewable-ppa-prices-fell-5-in-q1/ https://www.pv-magazine.com/2024/04/19/europes-renewable-ppa... says: > Energy consultancy LevelTen says that solar power purchase agreement (PPA) prices fell 5.9% in the first quarter of 2024, with decreases recorded in all analyzed countries except for Romania. It attributes the decline to lower wholesale electricity prices and a fall in solar module prices however, they haven't yet recovered to the 02020 levels, presumably because the astounding precipitous fall in module prices over the last year hasn't been priced in yet

huijzer 2y ago

Batteries are getting cheaper by the day too. Price per kWh halved in China in the last 2 years according to BloombergNEF (https://x.com/colinmckerrache/status/1800901575214514475 https://x.com/colinmckerrache/status/1800901575214514475).

fuzzfactor 2y ago

>Solar power is not. Often there is no battery, but regardless when solar cost goes up it could be due to expensive contractors in-between the panels and the installation & maintenance, before the lightbulb even gets a chance to see a single watt.

kragen 2y ago
a major reason in the usa is the tariff regime that has basically completely shut out chinese solar panels from the market; this makes solar panels in the us cost about twice as much as in the rest of the world