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Charging cars at home at night is not the way to go: study

news.stanford.edu

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Re: Charging cars at home at night is not the way to go: study

#271

Post by adrr »

mh8h wrote: post #239
_8j50 wrote: post #228

I need ELI5: electric cars have very large and heavy batteries right? Why is it prohibitively difficult to replace them on demand? What if there were 2-3 batteries charging at home or hundreds at a "battery station", where you would park at a spot/drive-thru garage and have a hydraulic machine drop your old battery and lift in a new battery and the whole swap can take no longer than the time it takes to fill up a has…

With the current way of owning an EV, you own the battery. And because batteries degrade overtime, the health of the battery is a big component of the value of your car. Using a service like that means you'll get a random battery every time you swap. I guess that can change if you lease the battery separately.

EVs will switch to LFP batteries that will have a life span of 300k miles with current technology and in 10 years will be at a million miles. Batteries will last longer than the cars.

Re: Charging cars at home at night is not the way to go: study

#273

Post by yjftsjthsd-h »

jonahhorowitz wrote: post #116
floatrock wrote: post #27

Earlier quoted context omitted.

> > Today, California has excess electricity during late mornings and early afternoons, thanks mainly to its solar capacity. If most EVs were to charge during these times, then the cheap power would be used instead of wasted. > How are people going to charge their cars during commutes? Come on, you're saying most commutes are "late morning and early afternoon"? I too would like a job where my commute in is at 11 and…

We should install solar panels over those lots at the same time. It covers some of the capacity need, cools the lot and the cars, and is an efficient use of space.

It would also conveniently reduce transmission loss, and if you did it right you could probably skip the inverter overhead by going all DC.

Re: Charging cars at home at night is not the way to go: study

#274

Post by Retric »

midasuni wrote: post #203
Scoundreller wrote: post #190

Earlier quoted context omitted.

Nice. I’ve also wanted my phone to tread water and not add charge while I’m driving. Dumb dumb to use a gasoline engine’s generator to charge it, but I don’t want it to go dead either.

The iPhone 13 pro max has a battery about 17Wh. A typical car uses 330 Wh per mile. Charging your phone from flat will cost you about 90 yards in range. At the most expensive electricity on the planet of about 70c per kWh it will cost you about 1c.

Engine > alternator > rectifier > wireless charger > battery isn’t particularly efficient so you could be looking at closer to 2c/charge depending on setup and gas prices. Still trivial compared to an iPhone.

Re: Charging cars at home at night is not the way to go: study

#275

Post by jjtheblunt »

parker_mountain wrote: post #257
jjtheblunt wrote: post #202

Earlier quoted context omitted.

my 2014 BMW i3 could be set to start charging when electricity was cheap (defined by me onscreen). it was a little buggy, as far as systems go, but it was the original model year (for north america, i think 2013 in europe).

A lot of newer charging stations in the US also have this built in, as well. You can hook them up to the internet, or do it manually. How mine works is pretty clever: you plug it in, and it asks you if you'd like to go to 100% now or wait until charging is cheaper. If you don't reply, it will fast charge your car to about 40%, and then wait.

that's EXACTLY the oversight in the 2013-2014 onboard firmware :

even though i didn't need a full charge at 8am, the car would realize it couldn't get to (the not important) full charge by 8am, which was the previous day time of departure, and would start charging while electricity was still expensive, because it decided maximal charge at previous day departure time was more important than cheap electricity.

Just an oversight...

Re: Charging cars at home at night is not the way to go: study

#277

Post by collinmcnulty »

cgb223 wrote: post #241
alexb_ wrote: post #17

>We're doing it wrong, according to a new Stanford study Wrong according to what metric? Cost? Raw efficiency? A lot of people are more than willing to give up efficiency so that they don't have to actually worry about finding a station during the day. To say that something is just outright "wrong" based on their personal preference of priorities comes off as unhelpful to me. The solution is simple. Make electricity…

> The solution is simple. Make electricity cheaper when it's more available, and people will use it. You don't need any complex "AI" like people in this thread are saying, you just use natural market forces and the problem fixes itself. Too much energy being used at night - price increases. It's not complicated, and it's what we're doing already. People don't need a Stanford study to convince them to get their energy…

Texas electricity prices are capped at $9/kWh but are often reported in the wholesale $/MWh

Re: Charging cars at home at night is not the way to go: study

#278

Post by Symbiote »

midasuni wrote: post #203
Scoundreller wrote: post #190

Earlier quoted context omitted.

Nice. I’ve also wanted my phone to tread water and not add charge while I’m driving. Dumb dumb to use a gasoline engine’s generator to charge it, but I don’t want it to go dead either.

The iPhone 13 pro max has a battery about 17Wh. A typical car uses 330 Wh per mile. Charging your phone from flat will cost you about 90 yards in range. At the most expensive electricity on the planet of about 70c per kWh it will cost you about 1c.

For what it's worth, and since this thread started with Denmark, the hourly price I was paying for an hour earlier this evening was 7.71DKK = 0.93USD.

A few days ago the price was almost zero (plus tax) for several windy hours.

https://andelenergi.dk/kundeservice/aftaler-og-priser/timepr... (add 1.59DKK for the taxes.)

Re: Charging cars at home at night is not the way to go: study

#279

Post by discretion22 »

yazaddaruvala wrote: post #266
Scoundreller wrote: post #193

Earlier quoted context omitted.

Ontario Canada did a mass $2b implementation of smart meters for time of day pricing. Unfortunately most people don’t care (or the technology to take advantage of it just isn’t there), and demand shifted less than 1% over several years. But it’s hard to find this info, because it doesn’t fit the (expensive to implement) narrative of “let them pay market price and people will respond to incentives”. https://www.cbc.ca…

I wouldn't judge this framework on a few year time horizon, but the time horizon to migrate to 100% EV fleet for Ontario. The problem with 100% EV fleet a regular grid will be overloaded and customer's will not be incentivized to care. This framework future proofs the Ontario grid from such a "wall". Now that the framework exists in Ontario, prices at certain times in the day can grow 10x, 100x, 1000x where appropria…

If time of use had even a 10x premium, people in Ontario would simply switch to simple tiered pricing which is available as an alternative to time of use pricing. Each Ontario electricity company is required to show you which would be cheaper for you and allow you to switch to the cheaper tariff to obtain cost savings.

Re: Charging cars at home at night is not the way to go: study

#280

Post by jacknews »

mh8h wrote: post #239
_8j50 wrote: post #228

I need ELI5: electric cars have very large and heavy batteries right? Why is it prohibitively difficult to replace them on demand? What if there were 2-3 batteries charging at home or hundreds at a "battery station", where you would park at a spot/drive-thru garage and have a hydraulic machine drop your old battery and lift in a new battery and the whole swap can take no longer than the time it takes to fill up a has…

With the current way of owning an EV, you own the battery. And because batteries degrade overtime, the health of the battery is a big component of the value of your car. Using a service like that means you'll get a random battery every time you swap. I guess that can change if you lease the battery separately.

Like with cooking gas cylinders?

If you don't own it, as long it's certified good and won't blow your car up it doesn't really matter if it's well-worn, etc?

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