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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

#351

Post by ZeroGravitas »

adgjlsfhk1 wrote: post #186
ZeroGravitas wrote: post #140

Earlier quoted context omitted.

These can actually be cheaper than the alternative to install, and get greater use (assuming the standard gets widely implemented). Definately going to be a thing. Loading/waiting areas for taxis and delivery vehicles seem like an early adopter market.

A wireless charger is cheaper than a power outlet?

Cheaper than an equivalent EV charger. Safety requires an isolating transformer in the charger, which adds costs and an efficiency loss. The wireless charger is the isolating transformer in their case, leading to surprisingly high efficiency and low costs in comparison.

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

#352

Post by jjav »

kwhitefoot wrote: post #125

Sounds like the problem is simply that the US doesn't seem to have real time pricing of electricity. In Norway we pay what the market determines is the current price. Most people don't have flat rate charges. I can see the spot price in real time in an app. Why isn't that good enough?

> the US doesn't seem to have real time pricing of electricity

"The US" is a big place. Depends which city/county you're in and who is providing the electric service.

> I can see the spot price in real time in an app.

That sounds like a nightmare. Does it really change hourly? How can you program your systems to use the most efficient rate if you have no idea in advance what it is?

Here in PG&E California we have time of use tiers, but they are known. So I can for example let the EV start charging only at midnight when the cheapest tier kicks in. But I know it is cheap midnight to 3pm, brutally expensive 3pm to 9pm and fairly expensive 9pm to midnight.

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

#353

Post by qqqwerty »

upsidesinclude wrote: post #224
qqqwerty wrote: post #166

Earlier quoted context omitted.

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 a…

Turn off fox news for a bit and try getting your information from reliable, nonpartisan sources. Currently, over 60% of Californias electricity comes from clean sources (hydro, renewables, and nuclear). And we are well on target to hit 100% before our goal of 2045. These are facts.

PG&E has nothing to do with this. Most power plants in the state are owned by third party investors, not by the utilities. Perhaps you should read up on CA power markets before commenting.

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

#354

Post by parker_mountain »

tsimionescu wrote: post #332
parker_mountain wrote: post #269

Earlier quoted context omitted.

"150 million people" There are over a billion iPhones in use worldwide. This technology is also being brought to MacBooks (100 million+), Watches (100 million+), and iPads (150 million+). Your fundamental numbers are staggeringly inaccurate. And, most crucially, representing it as a whole of the electric usage instead of peak hours intentionally misses the point of reducing peak hour usage. It's called "peak hour" fo…

And the total worldwide use of electricity is 22,848 TWh/year, (according to the IEA [0]). So that would be 5Wh/day * 1 billion phones * 366 days = 1,830 TWh = 0.0008% of world electricity consumption. Getting data about peak hour usage is much harder, but I would wager it's at most as much of that. So yes, completely insignificant at a large scale. If anything, the biggest impact will come to individual consumers, i…

> Getting data about peak hour usage is much harder

That is the entire point of this exercise. My point is that OP fails to address that with data (as do you).

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

#355

Post by jjav »

pornel wrote: post #205
greedo wrote: post #176

Earlier quoted context omitted.

Our lot isn't closed, and it's adjacent to a mall. So the only way we'd electrify each spot is with pay outlets (which is what the current 2 are). Otherwise we'd have people leeching off of the company.

You're overthinking this. The solution can be as trivial as putting a padlock on the power outlet. More practically, there are dispensers that read RFID cards, so employee badges can be used to grant access. It can be a raspberry-pi level tech, not a full-blown payment terminal.

This is a well-solved problem. My previous employer had all the chargers on the chargepoint network but only available to accounts which verified as employees.

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

#356

Post by tsimionescu »

parker_mountain wrote: post #354
tsimionescu wrote: post #332

Earlier quoted context omitted.

And the total worldwide use of electricity is 22,848 TWh/year, (according to the IEA [0]). So that would be 5Wh/day * 1 billion phones * 366 days = 1,830 TWh = 0.0008% of world electricity consumption. Getting data about peak hour usage is much harder, but I would wager it's at most as much of that. So yes, completely insignificant at a large scale. If anything, the biggest impact will come to individual consumers, i…

> Getting data about peak hour usage is much harder That is the entire point of this exercise. My point is that OP fails to address that with data (as do you).

Do you have some data? Or some reason to believe that iPhones are a much larger part of peak hour consumption than they are of overall electricity consumption?

Based on the data we do have, there doesn't seem to be any reason to care about iPhone charging - so, if you don't come up with some data or rationale for why we should, then I still feel it's justified to say that this change has little chance of helping the world in all but the most minor of ways.

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

#357

Post by ZeroGravitas »

wodenokoto wrote: post #326
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…

> Make electricity cheaper when it's more available, and people will use it. It’s _not_ like that in the states? In Denmark people are sharing spreadsheet that can tell you when to run the washing machine to save on electricity since the energy crisis following Russias invasion of Ukraine has pushed prices enough that these optimizations become valuable to regular consumers.

It's not like that in the States.

https://fsr.eui.eu/time-of-use-and-dynamic-pricing-rates-in-...

All the usual communist elements (Jimmy Carter, California) have been slowly making progress on introducing it since the 1970s, but mysteriously a lot of lies sprung up about how it would harm the poor. And the USA is really caring about the poor not using as much fossil fuels as they possibly can so it got kind of squashed.

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

#358

Post by midasuni »

Retric wrote: post #274
midasuni wrote: post #203

Earlier quoted context omitted.

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.

An iPhone probably last about 1000 charges (once a day for 3 years), so even 5c/charge would be $50, less than 5% of the total cost.

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

#359

Post by kwhitefoot »

jjav wrote: post #352
kwhitefoot wrote: post #125

Sounds like the problem is simply that the US doesn't seem to have real time pricing of electricity. In Norway we pay what the market determines is the current price. Most people don't have flat rate charges. I can see the spot price in real time in an app. Why isn't that good enough?

> the US doesn't seem to have real time pricing of electricity "The US" is a big place. Depends which city/county you're in and who is providing the electric service. > I can see the spot price in real time in an app. That sounds like a nightmare. Does it really change hourly? How can you program your systems to use the most efficient rate if you have no idea in advance what it is? Here in PG&E California we have tim…

It changes continuously but there are clear diurnal patterns.

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

#360

Post by bonzini »

vel0city wrote: post #171
bonzini wrote: post #112

Earlier quoted context omitted.

What? My house used 4 MWh a year in 2020, with two people working from home and two kids. Of these about half (IIRC) is self-produced solar. Stove and heating are gas and I do not have a tumble dryer, but does that justify a 10x difference??

My home uses over 2MWh/mo over the summer, I think our peak bill this year was ~3200kWh. Average highs these last few months has been around 100F or so and very sunny, with at least one month >100F for the high every day. Its finally "cooling off" around here, with our highs being in the upper 90s most days. Cooling >2000sqft of space, even with some decent insulation and keeping the AC to 78F in the day, uses a lot…

To be honest I wonder if those are good places for humans to live in, at all.
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