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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

#41

Post by lm28469 »

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…

> Wrong according to what metric?

Have you read the study ? https://www.nature.com/articles/s41560-022-01105-7

> you just use natural market forces and the problem fixes itself.

Never worked, never will, borderline sounds like a cult following, "The all mighty market will automagically fix it with no human intervention"

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

#42

Post by floatrock »

ctrlmeta wrote: post #24
kadoban wrote: post #12

Earlier quoted context omitted.

Charge at work.

But how many work areas have a charging station available easily?

Literally the point of the study

> “We encourage policymakers to consider utility rates that encourage day charging and incentivize investment in charging infrastructure to shift drivers from home to work for charging,” said the study’s co-senior author, Ram Rajagopal

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

#43

Post by lbriner »

denimnerd42 wrote: post #18

I would be curious about a study done for the Texas market. From what I understand, you'd definitely want to charge at night due to the vast amounts of wind power available and the otherwise low demand. Even better would be to plug the car in at all times when parked either at work or home and it just charges when the rate is cheapest. You don't need to charge every day to refill that 20 or 30 miles.

I guess the issue with this report is that it is specific to the unique mix of energy that the (west of the) USA has compared to other areas/countries. Countries with a lot of nuclear see that energy wasted at night because you can't just dial down the level very quickly, in that sense, in most of Nothern Europe this would be desirable.

In countries that have extreme levels of solar, clearly this only works during the day and perhaps leaves the night being covered by fossil fuel plants instead where they are happy to use less/dial it down.

The massive missing piece, at least in the UK, is a genuine Smart Grid that can drive usage to meet supply. I have precisely zero appliances in my house that can make any use of cheap electricity and even worse, if I want a dual-tariff to get cheaper overnight electric, I get punished for it costwise.

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

#44

Post by drdec »

function_seven wrote: post #30
goethes_kind wrote: post #13

Earlier quoted context omitted.

Yeah, except now each parking spot at work needs its own power outlet.

That would be the best part. Cover all that parking with solar panels, use those panels to partially or completely offset the charging demands of the cars parked under them. An average parking space has enough room for (napkin math...) 6kW of solar output. That's more than enough to offset a level 2 charger while the driver of that car is in the office. And it leaves the car cooler at the end of the say. Costs a bit…

>Cover all that parking with solar panels

This would help in many cases, but parking garages are a thing, even in my relatively small city. We would need a solution for them as well.

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

#45

Post by cortesoft »

It sounds like the real issue is that the time-of-use rates are wrong. Just adjust them to match the actual energy production/demand, and the behavior change will follow.

My solar, battery, and car setup automatically adjusts to the rate for power. It sends all my energy to the grid when costs are high and I get the most back, and uses the battery at that time... and then charges the battery when rates are low.

Set the rates to be accurate and the system will work itself out. I am not going to use more expensive electricity just because the rates are set wrong.

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

#46

Post by Gasp0de »

DropPanda wrote: post #34

This is very interesting and perfectly logical. I wrote a fairly recent report looking at a very similar question, and reached the opposite conclusion: night time charging is far better for the grid. That study however focuses on Sweden, where solar power only marginally impacts day-time supply. Link to the study: http://urn.kb.se/resolve?urn=urn%3Anbn%3Ase%3Ari%3Adiva-5752... If the western US has a surplus in morni…

Inductive charging seems like a horrible solution as it must surely be extremely inefficient? Also, if dynamic charging refers to charging while in motion, why would that be a good solution? It seems way more complicated and inefficient than charging while stationary, and personally owned cars are stationary more than 90% of the time.

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

#47

Post by sudden_dystopia »

EV’s are only a solution as far as renewable energy can keep up with electricity demands. And that doesn’t appear to be the case right now. Coupled with the mining of minerals, violent venting of batteries, and non-recyclable/non disposable nature of the batteries it’s not obvious that EV’s are more environmentally friendly.

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

#48

Post by chipsa »

goethes_kind wrote: post #13
3pt14159 wrote: post #4

This is simple. Musk just needs to throw 1% of his AI talent at optimizing charging times via realtime grid negotiating and nobody will need to even think about this. Cars will turn into one of our most valuable assets as they help stabalize the grid by being both sinks when energy is plentiful and sources when it's not. There are certain problems we all need to think about, but this is not one of them. It will effec…

Yeah, except now each parking spot at work needs its own power outlet.

Future is SAE J2954 (aka Witricity): you have a wireless charging pad under each parking spot. No screwing with power plugs, just park and go. This isn't ideal for fast charging, but for the slower charging you'd get from being somewhere for 6-8 hours, it's perfectly fine. You still need to run power to every parking spot, but now it's embedded in the ground, and you don't have to worry about someone just coming around with cable cutters and stealing it.

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

#49

Post by alexb_ »

lm28469 wrote: post #41
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…

> Wrong according to what metric? Have you read the study ? https://www.nature.com/articles/s41560-022-01105-7 > you just use natural market forces and the problem fixes itself. Never worked, never will, borderline sounds like a cult following, "The all mighty market will automagically fix it with no human intervention"

A very small amount of people really care about "grid impact" enough to change their behavior. They do care about "I can make my electricity cheaper" or "My electricity bill went up".

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

#50

Post by wongarsu »

Skimming the article it seems the crux of the matter is that with home charging people charge either a) when they come home b) with a timer, at 9pm, or c) with a timer, at 12am (with b and c driven by fixed changes in electricity prices). Electricity demand for everything else is highest at about 7pm, so both a and b charge at times where there isn't a lot of unused grid capacity. And to make things worse, at all three times you don't get a lot of solar power.

I wonder why the recommendation is to go to daytime charging, instead of timers staggered around 4am (when grid utilization is lowest). Sure, no solar, but potentially lots of unused wind, and lots of spare capacity on the power lines that already exist.

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