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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

#341

Post by nikau »

notatoad wrote: post #99
GoOnThenDoTell wrote: post #55

Earlier quoted context omitted.

time-of-use is also cognitive load that can cause anxiety

it is, but that's the part that technology can actually help us with. all the internet-connected smart home stuff that companies have been trying to sell us is a bit silly when electricity is sold at a flat rate, but if my car charger, my clothes dryer, or my or my dishwasher could sit idle until electricity prices drop into the cheap zone and then turn themselves on, that internet connection becomes useful. an attit…

Yep that could certainly work if appliances and cars have an option to say "have my dishwasher finish or car charged by 9am tomorrow" and it knows how long a cycle takes and picks the best time.

For anything real time it wont work - here in Australia we had a discount for a box that you connect to your air conditioner which would throttle back its use during peak, and a lot of people ditched it due to impact on their comfort.

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

#342

Post by nikau »

tsimionescu wrote: post #337
kevinpet wrote: post #222

Earlier quoted context omitted.

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%.

They were saying this creates huge problems for the grid. Let's assume people will want to destroy their car battery by draining it to power their house every night, and that this indeed supplements the need for grid storage overnight. However, when holiday seasons comes around, all of a sudden a significant percentage of homes will start demanding much higher power usage from the grid, as people co-ordinate in setti…

Sounds like the UK where everyone used to turn their kettles on during the ad breaks of popular TV shows

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

#343

Post by Test0129 »

sidewndr46 wrote: post #261
Traubenfuchs wrote: post #229

Did anyone do the math for when gasoline car sales will be banned? How many more power plants to we need? How much more Lithium do we need? I don‘t want to be a luddite, but the ev revolution seems to be unfeasible.

As long as the internal combustion engine is banned the EV revolution is entirely feasible. No one said everyone would be able to afford to drive an EV. Just that people would stop driving internal combustion engine vehicles.

No one has answered how people intend to do things that require transportable fuel. I can't buy a Tesla (or whatever) and hot-swap batteries. If I travel 200 miles to go camping and the nearest charging station is 150 miles away I am hosed. No electric vehicle to date (nor planned for release) has the towing capacity needed to haul a week or two of gear, solar panels, deep cycle batteries, alternators, etc needed to set up a system. Even if you could, the risk of starting a forest fire due to reflections and/or sudden spontaneous battery deconstruction is non-negligible. The torque of an electric truck makes it attractive as an off road vehicle, however it's entirely infeasible in practice.

So the government rules by fiat that ICE vehicles are to be banned. I guess someone better tell people that they won't be able to travel as far, or for as long, until the 22nd century when battery technology catches up and you can charge it with a single lightweight panel where ever you are. The energy density of a can of gasoline is so much higher than a towable array of solar panels the EV solution may as well be horse and buggy. It will be decades before remote gas stations in the middle of no where have a charging station available.

The government can "ban" things all they want. If the alternative isn't acceptable to people who don't want to live a life of being a metropolitan worker drone who owns nothing they will find a way.

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

#344

Post by brabel »

vanviegen wrote: post #331
wodenokoto wrote: post #326

Earlier quoted context omitted.

> 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.

Is hourly pricing the norm in Denmark?

There are apps that track the prices and can automatically "trigger" charging when it's cheaper.

Found these examples by quickly googling:

https://www.trueenergy.io/app/

https://play.google.com/store/apps/details?id=com.sense.andr...

https://play.google.com/store/apps/details?id=com.tibber.and...

EDIT: to answer the question: yes, these apps use something called "Nord Pool" which publishes hourly electricity prices (in Swedish): https://elavtal24.com/blogg/tibber-greenely/

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

#345

Post by jjav »

shiftpgdn wrote: post #94
landemva wrote: post #86

Earlier quoted context omitted.

For the small amount I consume, tiny potential savings are not worth the mental hassles. I switched a residence to flat rate to avoid these mental games.

My house uses around 3-4MW/mo. I hyper optimized when I had true spot pricing before Griddy energy was disbanded by the state. My bill was extremely low compared to what I pay now.

> My house uses around 3-4MW/mo.

This sounds.. astonishing. How can one consume so much in a house?

My average is around 500 kWh which results in a $200+ bill.

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

#347

Post by tetha »

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.

Hamburg the city is currently funding a fairly interesting research project. The problem here is that solar + wind at times overproduces, and we have no grid scale energy storage to keep that power. So, a short-term idea is to equip most larger garages with EV chargers and to include a central control unit for these chargers. This way, the grid can bring the EVs to 40% - 60% charge slowly during off-hours, or dump as much power into the EVs as possible if the alternative was to shut down solar plants or wind turbines.

And additionally, centralizing the power usage simplifies transmission issues for now. It's much easier to have a few big cables to a few big buildings, than having every single home pulling a lot of power all of a sudden.

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

#348

Post by jjav »

sidewndr46 wrote: post #251
tacostakohashi wrote: post #231

Earlier quoted context omitted.

We're talking about an industry that has failed to standardize on a single, interchangeable charging plug here. What do you think the chances of a single, interchangeable battery for such a "battery station" to remove, recharge, replace are? Or are you proposing such stations for each individual manufacturer, model, model year, etc?

Let's just ignore the total of end-user standardization like a charging plug. They can't even put the gas filler on the same side universally on all vehicles. They can't even make the way you access it universal. Ever seen a car from the 70s where it was hidden behind the license plate?

> They can't even put the gas filler on the same side universally on all vehicles.

The side is a a non-issue. The important part is that the hose connection is standard. Any ICE car I could possibly buy can be fueled at any gas station anywhere, the hose always works.

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

#349

Post by coderenegade »

xboxnolifes wrote: post #189
lm28469 wrote: post #54

Earlier quoted context omitted.

They don't care until their whole neighbourhood goes dark at 6PM everyday

They still won't care to change . They will complain, yes, but change? No.

That seems fairly reasonable to me? Most people are just trying to get by. They have bigger problems on their plate like getting paid so they can pay their bills on time, and keep a roof over their head. Adding additional stuff on top of that is a cognitive load that most people would rightfully push back against, because they don't have the spare capacity.

I think this is a big part of why, to-date, the environmental movement is comprised of the relatively wealthy, and what I would characterize as "true believers" who don't have much, but are okay with that, and okay with living their lives in a way that minimizes their impact. The first group have the spare capacity to do something about their impact, and the second group take it on as a mandate that often (but not always) affects their ability to function in broader society (or: how do you hold down a decent job if you ride a pushbike everywhere?).

My personal belief is that any successful environmental movement needs to go hand-in-hand with a more equitable distribution of wealth in society, and focus on quality-of-life, so that the people in the middle have the spare capacity to give a shit. Otherwise, you're going to bump into the ugly reality of people's day-to-day, and your movement will be perceived as rich people -- who make up the bulk of consumption to begin with -- telling everybody else how to live their lives. Which is exactly what's happened. I don't think it's an accident that the countries farthest along the path to decarbonization also have some of the best income equality, and quality-of-life on the planet.

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

#350

Post by jjav »

mabbo wrote: post #281
_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…

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…

> You get home, you plug in

Assuming a common work schedule, that would put you into plugging in at the most expensive peak tier pricing ($0.72c/kW here in PG&E land).

When we had the EV I had a timer on the charger to only turn on at midnight when the off-peak rates kick in. If one had to leave early in the morning, the car was never fully charged.

It worked ok most of the time as my partner could charge it up to 100% for free at work, but without that perk it was iffy.

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