4 ms·

I do wonder, how significant are inefficiencies in transmission, charging, and storage? With cheap lithium batteries I've bought (like phone power banks), I usu

I do wonder, how significant are inefficiencies in transmission, charging, and storage? With cheap lithium batteries I've bought (like phone power banks), I usually need to subtract about 25% from the rated capacity to figure out how many times it'll fill my phone's battery. Although hopefully cars are more efficient

jeeeb 5y ago
Your right! I was just looking at it from the point of view of how efficient does this standard require power plants to be, since 270g of CO2 to run a 1kw heater for an hour seemed high. If you look at the whole energy supply chain though the picture is probably a lot worse for both, in particular when you account for things like methane leaks or the emissions from transporting + refining oil.
- deleted 5y ago
  [deleted]
arcticbull 5y ago
Losses on the big high-voltage wires average about 2% in the US. Losses on lower-voltage distribution wires average 4% on top of that - so about 6% in total. [1] Lithium Ion batteries charge near 100% efficiency. [2] In terms of storage (specifically self-discharge), Lithium Ion batteries lose 5% in 24 hours, then 1-2% per month thereafter - but can be as low as 0.35% per month. [3, 4] [1] http://insideenergy.org/2015/11/06/lost-in-transmission-how-much-electricity-disappears-between-a-power-plant-and-your-plug/ http://insideenergy.org/2015/11/06/lost-in-transmission-how-... [2] https://www.powertechsystems.eu/home/tech-corner/lithium-ion-battery-advantages/ https://www.powertechsystems.eu/home/tech-corner/lithium-ion... [3] https://batteryuniversity.com/article/bu-802b-what-does-elevated-self-discharge-do%C2%A0 https://batteryuniversity.com/article/bu-802b-what-does-elev... [4] https://en.wikipedia.org/wiki/Lithium-ion_battery https://en.wikipedia.org/wiki/Lithium-ion_battery
- _fizz_buzz_ 5y ago
  > Lithium Ion batteries charge near 100% efficiency The power electronics to charge the battery also have losses. Although they are getting really good, my guess would be something better than 95% efficiency in the battery charger. There are some really great improvements in power transistors recently though, so this number will still have some room for improvement.
  - arcticbull 5y ago
    Thank you for calling that out. I was going to say something about that, and budget say 10% to switching regulators. With car-scale charging systems I just didn't have enough data to ballpark efficiency.

jeeeb 5y ago

Your right! I was just looking at it from the point of view of how efficient does this standard require power plants to be, since 270g of CO2 to run a 1kw heater for an hour seemed high. If you look at the whole energy supply chain though the picture is probably a lot worse for both, in particular when you account for things like methane leaks or the emissions from transporting + refining oil.

deleted 5y ago
[deleted]

arcticbull 5y ago

Losses on the big high-voltage wires average about 2% in the US. Losses on lower-voltage distribution wires average 4% on top of that - so about 6% in total. [1] Lithium Ion batteries charge near 100% efficiency. [2] In terms of storage (specifically self-discharge), Lithium Ion batteries lose 5% in 24 hours, then 1-2% per month thereafter - but can be as low as 0.35% per month. [3, 4] [1] http://insideenergy.org/2015/11/06/lost-in-transmission-how-much-electricity-disappears-between-a-power-plant-and-your-plug/ http://insideenergy.org/2015/11/06/lost-in-transmission-how-... [2] https://www.powertechsystems.eu/home/tech-corner/lithium-ion-battery-advantages/ https://www.powertechsystems.eu/home/tech-corner/lithium-ion... [3] https://batteryuniversity.com/article/bu-802b-what-does-elevated-self-discharge-do%C2%A0 https://batteryuniversity.com/article/bu-802b-what-does-elev... [4] https://en.wikipedia.org/wiki/Lithium-ion_battery https://en.wikipedia.org/wiki/Lithium-ion_battery

_fizz_buzz_ 5y ago
> Lithium Ion batteries charge near 100% efficiency The power electronics to charge the battery also have losses. Although they are getting really good, my guess would be something better than 95% efficiency in the battery charger. There are some really great improvements in power transistors recently though, so this number will still have some room for improvement.
- arcticbull 5y ago
  Thank you for calling that out. I was going to say something about that, and budget say 10% to switching regulators. With car-scale charging systems I just didn't have enough data to ballpark efficiency.