Charging cars at home at night is not the way to go: study • Hacker News Board

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

#361

Post by elihu » Sat, Sep 24, 2022, 9:07 AM UTC

_8j50 wrote: post #286

elihu wrote: post #285

Earlier quoted context omitted.

Battery swap stations are an old idea, but it's really hard to actually pull it off. It requires that all the cars you service have the same battery pack, or that there are at most only a few kinds of battery pack to deal with. The packs have to be stored and charged, so you have the same electrical service requirements plus you need a place to store the batteries, and employees or robots to move them around. You nee…

As a sibling commenter pointed out, NIO is already doing this with millions of swaps already in China. Instead of electrifying roads for cars, why not electrify them for rail cars and trains?

Converting trains over to electric is also well worth doing.

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

#362

Post by davidro80 » Sat, Sep 24, 2022, 10:13 AM UTC

greedo wrote: post #113

floatrock wrote: post #40

Earlier quoted context omitted.

It's almost as if the logical conclusion is to invest in convenient workplace charging infrastructure so charging is simple when the car is conveniently parked at work doing nothing and the owner wants a car ready to go home in the evening... > “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 c…

The logical conclusion is to try to get away from needing to drive to work at all.

No post body was provided.

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

#363

Post by mabbo » Sat, Sep 24, 2022, 10:58 AM UTC

_8j50 wrote: post #289

mabbo wrote: post #281

Earlier quoted context omitted.

I think the problem is that you are thinking of things purely in terms of how gas stations and gas powered cars work. You need to step back and re-think. For almost all EV owners, a level 2 (240V 20amp) charger at home is all that's needed[0]. It charges slowly, but given the car sits for 12+ hours every night, it's more than enough. You get home, you plug in, you go eat dinner and go to bed. When it's time to go in…

And you are only thinking in terms of rich home owners. I get paid verg well and I still can't afford a house. How am I going to charge at an apartment? Do you think they will spend millions converting every parking lot into a charger and maintaining it? Or would I have to stand in line at a charging station? This is one the main reasons I vehemently oppose any idea that promotes electric cars the way they are. We st…

> How am I going to charge at an apartment? Do you think they will spend millions converting every parking lot into a charger and maintaining it?

I live in a condo actually. I'll tell you how: we passed laws in my province that say the condo must assist me when I decide to install a charger. Other jurisdictions are following this pattern. Also: not millions. As I said, it's relatively inexpensive to install a level 2 charger. For a 200 unit parking lot, you'd be wildly overcharged at a million dollars. And providing level 1 charging is as cheap as running extension cords from Walmart.

And hey, don't all your arguments work just a well for when electric lighting and heating first appeared? And yet somehow, all apartments today have it.

> Ugh, NIO is already doing this in China and I'm pretty sure it's cheaper.

They aren't on any real scale, and it's not cheaper overall- just massively subsidized. You know what is cheap? The ubiquitous electrical system that's already everywhere.

> Also, the government is literally spending hundreds of billions to subsidize electric car infrastructure

Source on those numbers? And what is "electric car infrastructure"? You mean the standard electric grid that's already ubiquitous? The EV subsidies are drying up quickly. Adoption of the tech is at the inflection point that the free market is handling the problems just fine.

You've decided how the world "ought to be" and don't care much that the rest of us have solved these problems just fine and have moved on.

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

#364

Post by ZeroGravitas » Sat, Sep 24, 2022, 11:03 AM UTC

tsimionescu wrote: post #356

parker_mountain wrote: post #354

Earlier quoted context omitted.

> 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…

Recent price rises due to gas in Europe have exposed more people to the idea that the market price is set at the margin.

If 1W of gas fired power needs to be brought online in the middle of the night to charge your phone, then all the wind power gets the same price. That's why peaks have always been the most economical place to target investments.

It would be interesting to compare the charge rate of a Tesla Powerall * the number of them deployed. I can see iPhones alone winning that depending on some assumptions you make.

You'd then probably be able to find stats on what Tesla gets paid for providing that service to get some idea of scale.

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

#365

Post by Retric » Sat, Sep 24, 2022, 11:24 AM UTC

midasuni wrote: post #358

Retric wrote: post #274

Earlier quoted context omitted.

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.

Sure, though it is well worth it to replace the battery on an old iPhone.

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

#366

Post by adgjlsfhk1 » Sat, Sep 24, 2022, 12:49 PM UTC

ZeroGravitas wrote: post #351

adgjlsfhk1 wrote: post #186

Earlier quoted context omitted.

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.

have you ever looked at a level 2 charger? it's literally just a beefy extension cord.

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

#367

Post by PaulDavisThe1st » Sat, Sep 24, 2022, 2:06 PM UTC

upsidesinclude wrote: post #328

PaulDavisThe1st wrote: post #320

Earlier quoted context omitted.

I live near Santa Fe at 6000'. I have a 6.6kW array out front. It generates 3x what we need in the summer, and 1/3rd of what we need in the winter, when we heat with an air source heat pump. Yes, it's an old adobe and not well insulated, but even with those things fixed, the amount of power we'd need to stay warm would require a battery system of immense size, much larger than a car (for now, anyway).

From two googlings, avg home consumption daily : 30kwh Avg EV consumption per 100mi : 30kwh That is about a third of a typical modern vehicle range. Sounds like an adequate amount for your needs, but what you really should do is install passive solar heating like a thermal mass. If you're in Santa Fe then you already know the what and how. There's about 325 days of sunshine over there

The average daily home consumption does not typically include electric heating. Most homes in the US use oil or gas for heat. Even though heat pumps are very efficient, it still requires quite a lot of energy.

Given that our house is mostly constructed of double adobe (24" thick) walls, we have lots of thermal mass, and some notable passive solar design features too.

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

#368

Post by zbrozek » Sat, Sep 24, 2022, 2:12 PM UTC

landemva wrote: post #294

zbrozek wrote: post #177

Earlier quoted context omitted.

Sortof? The chumps left behind have fewer people to help amortize fixed costs.

Hawaiian islands have struggled with this for a decade. Rich people put up solar cells with usage offsets and get grid scale reliability on the backs of those who can't put up solar cells due to being poor or living in an apartment.

I'm going a step further. No grid connection at all. Uptime isn't great anyway-about 87% in July in my neighborhood.

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

#369

Post by vel0city » Sat, Sep 24, 2022, 2:55 PM UTC

bonzini wrote: post #360

vel0city wrote: post #171

Earlier quoted context omitted.

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.

There's only a narrow band of land then where we would be able to live without expending large amounts of energy to stay warm or cool.

Colder places use just as much if not more energy in wintertime. They just don't often use it as kWh from their electricity provider so they don't normally compare it this way. Instead of electricity they burn natural gas or propane or fuel oil or even wood pellets to heat their homes. Many people in this chat which talk about having pretty low energy usage then acknowledge they heat with gas.

For many, changing to heat pumps would drastically increase their electric bills in the winter offsetting their gas bills. Just look at my comparison of energy usage of my heat pump cooling my home compared to the energy usage of other big usage areas. It's not even close.

Running a heat pump for 12 hours to keep the house warm would be a similar amount of energy usage. It's the same tech. Raising the inside temperature from 0F to 70F (70F degrees of difference) takes more energy than cooling from 100F to 70F (30F of difference). So a place that spends half the year around 100F but then is close to comfortable inside for the other half requires less energy than a place that gets down to 0F half the year and then is close to comfortable the other.

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

#370

Post by _8j50 » Sat, Sep 24, 2022, 2:55 PM UTC

vinnymac wrote: post #306

theluketaylor wrote: post #305

Earlier quoted context omitted.

Way more complex than that. Different packs have very different voltage and current delivery characteristics. A bunch of motor management depends on the battery pack characteristics, including things like regen braking. Charge times are already under 20 minutes for the best cars and will likely continue to come down. Swappable batteries would be a massively expensive undertaking that would hugely limit innovation in…

I agree. The newer charging stations are so quick at a rest stop, that I don't even notice them anymore. Once it's down to 10 minutes, it won't even be a discussion topic imo.

I would say 5min. 10min is nothing on a road trip but a lot when you are running late for something. People who make less money tend to care more about this.