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

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

#221

Post by maxerickson »

denimnerd42 wrote: post #102
parkingrift wrote: post #89

Earlier quoted context omitted.

>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. 99% of people have a fixed rate 24/7/365. I live in NYC and I'm not even sure if it's possible for me to pay time of use rates. The time of day that electricity is cheapest is... all the time. I sincerely doubt there is any public or political will to change this engrained billing me…

In Texas right now you can get two meters to your home. One meter you use a fixed rate plan and the other meter you use a "wholesale" plus fee type plan, infamous example being Griddy. When the rate is nearly free you enable the outlet that charges your car. Of course hiring an electrician and all of that would probably have a long payback period.

That's one of those things that works great if you use a huge amount of power.

The fixed rate cost of charging for my commute would probably be less than the connection fee for the 2nd meter. In that scenario it wouldn't pay off it all (and of course you wouldn't bother doing it).

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

#222

Post by kevinpet »

NickM wrote: post #97
Schroedingersat wrote: post #85

Earlier quoted context omitted.

I wonder if there's any correlation between times someone travels 400 miles and times when they are not home... we probably need a study or something to figure it out.

The problem is, you need a full charge in the morning if you're leaving on a road trip, so then your car will not be powering your house the night before. This would likely lead to big spikes in demand the night before the start of holiday a weekend, for example.

I don't have an electric car, but I can't imagine this is a challenging problem at all. All you need is a target charge level. If you're going on a trip tomorrow, set it to 100%. If your normal commute is 20 minutes, no reason to charge past 75% or even 50%.

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

#223

Post by KennyBlanken »

ars wrote: post #199
dybber wrote: post #169

Earlier quoted context omitted.

If all iPhones do this it will matter. Charging when energy is plentiful also means that electricity is more likely to come from renewables.

> If all iPhones do this it will matter. No it won't. An phone has around 5 watt hours. So: 5 watt hours / day * 150 million people * 365 days = 273GWh / year / 4,116 billion kilowatthours / year = 0.006651% of electrical usage. Yah, it's virtue signaling, not anything real. And keep in mind 0.006651% is total electrical usage - this time shifting might save 10%, so actual savings are even less than that.

[flagged]

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

#224

Post by upsidesinclude »

qqqwerty wrote: post #166
upsidesinclude wrote: post #104

Earlier quoted context omitted.

If we're seriously going there , then legislate mandatory carpool or motorcycles for single occupants. The thing is, California isn't making great policy decisions or even efficient power decisions. They are making virtue decisions. Moving 1.5 tons of battery or 1.25 tons of battery isn't where the hairsplitting should take place

They are making politically expedient decisions that move the state towards its clean energy commitments. Yes, there may be some hiccups down the road, but that is the price to pay for putting off the transition for so long. And as one of the faster movers in this space CA will almost undoubtedly move the market in a way that will make it cheaper and easier for everyone else. Look at the "California Solar Initiative"…

Have you seen BART? The freeways in every major metro of CA?

You are defending politics and not engaging the reality of failed infrastructure in the state.

Now they are going to lead the country in developing a new paradigm in power infrastructure? The same that has PG&E blowing up neighborhoods because the company got so much tax incentive to continue building they failed to record where they placed capital assets and can't complete maintenance.

California isn't putting anything off, they just can't get anything done.

Giving tax incentives to get more people to buy e-cars won't fix that problem

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

#225

Post by CameronNemo »

This will happen when/if TOU rates change, which will happen when/if solar gets built way out... There is a lot of inertia in the grid. No need to rush things and mess with incentives without good reason.

Being receptive to and prepared for employers who want to offer EV charging is a good idea, but it is definitely early days. No need to panic and implement a bad solution.

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

#226

Post by spoonjim »

JohnFen wrote: post #213
spoonjim wrote: post #161

Earlier quoted context omitted.

LOL. This is classic “virtue signaling.” Your iPhone battery is not even a rounding error on your electricity consumption.

"virtue signaling" is doing something useless in order to make yourself look good to a particular group. Could it be that this isn't "virtue signaling", but rather people overestimating the impact of the action? In other words, an honest (if mistaken) attempt at doing a good thing rather than just wanting to be perceived as doing a good thing?

I think many virtue signalers are earnest and think that Tweeting #BLM or other useless actions are actually useful.

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

#227

Post by m0RRSIYB0Zq8MgL »

CameronNemo wrote: post #220
m0RRSIYB0Zq8MgL wrote: post #174

Earlier quoted context omitted.

My post wasn't not about criticizing EVs. My post was about criticizing the energy grid. I think "slow" charging over night is the best way to use EVs and an energy grid that cannot accommodate that (because of a predominance of PV) should be criticized.

Is a level 2 charger not slow enough? Running that for 2-4 hours should be enough for normal commutes I imagine.

I was referring to level 2 chargers.

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

#228

Post by _8j50 »

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 car and you have less queues. Why is this not possible?

If it takes an hour to charge a battery and a battery station has 200 charging at any given time, and it takes 2 minutes to swap a battery then 6 charging bays can replace batteries for 180 cars leaving 20 extra batteries for defects and other issues. Couldn't such a charging station be implemented on a similar lot and budget of constructing a medium size gas station (at least a dozen pumps and around 1 acre lot).

A charging station that is twice as efficient with a 30min charge time can do 2 cars at most in one hour. You need 90 charging station to reach that efficiency even without considering the queues.

I just don't get it. Governments around the world and spending trillions on this stuff so why is there no clear answer on this?

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

#230

Post by spoonjim »

KennyBlanken wrote: post #223
ars wrote: post #199

Earlier quoted context omitted.

> If all iPhones do this it will matter. No it won't. An phone has around 5 watt hours. So: 5 watt hours / day * 150 million people * 365 days = 273GWh / year / 4,116 billion kilowatthours / year = 0.006651% of electrical usage. Yah, it's virtue signaling, not anything real. And keep in mind 0.006651% is total electrical usage - this time shifting might save 10%, so actual savings are even less than that.

[flagged]

No. Do you celebrate programmers fixing 1 in a million cosmetic bugs when the software crashes on boot and deletes the user’s disk?
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