EV general discussion

[Bear]

really?

maybe 1 in 1000 own an electric vehicle and yet you are surprised wireless charging isn't available?

maybe once the figure is 9 in 10 then i would be surprised. but not at this moment in time

Its more that wireless charging is about 75 to 80% efficient, so if you have a 100kW charger you are going to lose 20 to 25kW in heat and losses so not only the charging will be slower, you would use more energy to charge up the battery but things would get damn hot and melt everythng in the vacinity. Have a 7kW home wireless charger then you could have a 1.4 to 1.75kW heater sitting outside killing your battery and melting your car

 

[Jez]

EVs aren't for everyone, and yeah, if you live in the country, miles from any public chargers, and regularly do 100 miles a day, then an EV probably isn't for you (yet). It's not really a relevant point for the majority of the population though, and certainly where EVs are needed most (where air pollution is above legal limits).

I live in the country and do a 130-140 mile commute every day. I doubt i would ever use a public charger (I'd install a big home charger and have regular predicable usage) and even for me i would think that a decent EV such as a model S/3 would be fantastic. There has been heavy Model S & X adoption for years in my area (you see tons of X and S's everywhere) in the Oxfordshire countryside, everyone uses them to commute into London (65 miles away from us, M40).

The point of my ramble being that even us folk in the country have been heavily using EVs for years now. I'm yet to make the jump from a large diesel, but i really will have to think about whether i get another typical obvious big Merc/BMW diesel as my next commuter.

 

[jpaul]

Are you even considering an EV? I'm all for an open discussion with viewpoints from all sides but it's kinda like someone who's diehard Xbox constantly posting in a PS5 thread.

I want to establish if the numbers make sense ... as ever, the true cost of running cars is often masked, in spades so, for the ev revolution, with congestion/eco charge factors;
you can pay up for a PCP, offsetting the risk, in exchange for some additional cash, but, so far, have purchased directly.

Currently wedded to the estate, or hatchback practicality, so, I'm not enthousiastic about the design of most of the current offerings : Kona doesn't seem bad,
but "...who's that , the next cargirl " , I'd missed that VW seem to be talking about an ID 3 variant
https://www.thisismoney.co.uk/money...lectric-family-estate-car-promising-2021.html

 

[Skillmister]

So my dad successfully completed a 2500 mile road trip around France, down into Italy and back in his I-Pace over a couple of weeks around Christmas.

Before anyone jumps in and says well that would have been far better in an ICE car, well yeah obviously from some perspectives.

But it was a very well planned trip utilising rapid chargers in places they actually wanted to visit and hotels with chargers. I think there were a couple of necessary detours when range anxiety kicked in especially with the cold affecting the distance but not much trouble.

I'm hoping he's going to write a blog piece about it or something, I can imagine some of the EV outlets would be interested in a real world experience. If he does put any words to page I'll share

I think the biggest take away was that in a lot of places where there were multiple chargers some would not be working and he had to ring helplines a few times to get them to reset or something. Some had to try multiple charge cards or credit cards. One only worked if he kept the language in French so some work to do there when things get busier

 

[Psycho Sonny]

Its more that wireless charging is about 75 to 80% efficient, so if you have a 100kW charger you are going to lose 20 to 25kW in heat and losses so not only the charging will be slower, you would use more energy to charge up the battery but things would get damn hot and melt everythng in the vacinity. Have a 7kW home wireless charger then you could have a 1.4 to 1.75kW heater sitting outside killing your battery and melting your car

I made that point long ago in the thread too. They would be terribly inefficient.

Anything that doesn't involve a direct wire to the grid will be inefficient.

 

[Matthew.M]

More misinformation based on assumptions!

Wireless charging exists on BMW hybrids in the US today. But the capital costs are large - you need a pad and for it to be invisible this needs to be sunken into the driveway. This is 85% efficient current gen.

Prototypes already exist for wireless charging which are just as efficient as using a cable. I saw a BMW prototype on an owners club day and they were quoting high 90% on the working demo. Alignment is the issue, the screen has to help you park very carefully. And again, cost. Are people really going to spend lots on a pad to save a few seconds plugging in a day? If you google wireless ev charging and efficiency there are a few articles on it.

If there’s demand it’ll be popular soon.

 

[Bear]

More misinformation based on assumptions!

Wireless charging exists on BMW hybrids in the US today. But the capital costs are large - you need a pad and for it to be invisible this needs to be sunken into the driveway. This is 85% efficient current gen.

Prototypes already exist for wireless charging which are just as efficient as using a cable. I saw a BMW prototype on an owners club day and they were quoting high 90% on the working demo. Alignment is the issue, the screen has to help you park very carefully. And again, cost. Are people really going to spend lots on a pad to save a few seconds plugging in a day? If you google wireless ev charging and efficiency there are a few articles on it.

If there’s demand it’ll be popular soon.

How can it be misinformation? Lets take your figures then, you quote high 90% efficiency so for a 100kW charger for say 95% efficiency you are still losing 5kW! For a 7kW home charger it may be manageable but fast charging seems a long way off even for 99% efficiencies. For your current gen 85% your home charger will still be losing 1kW! This is wasted energy and heat

 

[Psycho Sonny]

More misinformation based on assumptions!

Wireless charging exists on BMW hybrids in the US today. But the capital costs are large - you need a pad and for it to be invisible this needs to be sunken into the driveway. This is 85% efficient current gen.

Prototypes already exist for wireless charging which are just as efficient as using a cable. I saw a BMW prototype on an owners club day and they were quoting high 90% on the working demo. Alignment is the issue, the screen has to help you park very carefully. And again, cost. Are people really going to spend lots on a pad to save a few seconds plugging in a day? If you google wireless ev charging and efficiency there are a few articles on it.

If there’s demand it’ll be popular soon.

10-15% loss isn't efficient in my book

for something to be efficient in todays age it has to have loss of 5% maximum. ideally 1-2% though should be the aim if they can't hit 0% loss.

again who is going to pay £10K on top to have their driveway dug up and replaced? Far easier and cheaper to just have them install a charging point directly on the driveway that you just run a wire to.

I don't see wireless charging of a car to take off unless it's a public charging space.

 

[Jez]

Even 1% is a massive loss to take as a consumer paying for tens of thousands of miles of power. A non starter unless it could eventually get to the >99% range.

 

[mjt]

Is wireless charging really necessary, especially at home? Plugging in and unplugging my i3 takes seconds. It even lights up when you unlock the car or unplug the cable at the mains so I don't need to turn on the light in the garage.
Coupled with ANY loss makes it even less necessary. Literally money up in thin air.

 

[Psycho Sonny]

Even 1% is a massive loss to take as a consumer paying for tens of thousands of miles of power. A non starter unless it could eventually get to the >99% range.

Isn't electric £ per mile supposed to be 1/3rd of petrol/diesel?

Therefore losing 1% isn't a massive loss in comparison of cost. But in terms of if the whole country was doing it then yeah. The greta thunberg's of this world would never let it happen.

 

[sovietspybob]

I wonder whether the wireless charging thing is being pushed by people who haven't used an EV, as i've never heard anyone who owns one complain about it, as like others have said it takes seconds as you get out of the car before you go in to the house, it's pretty much a non issue?

 

[b0rn2sk8]

More misinformation based on assumptions!

Wireless charging exists on BMW hybrids in the US today. But the capital costs are large - you need a pad and for it to be invisible this needs to be sunken into the driveway. This is 85% efficient current gen.

Prototypes already exist for wireless charging which are just as efficient as using a cable. I saw a BMW prototype on an owners club day and they were quoting high 90% on the working demo. Alignment is the issue, the screen has to help you park very carefully. And again, cost. Are people really going to spend lots on a pad to save a few seconds plugging in a day? If you google wireless ev charging and efficiency there are a few articles on it.

If there’s demand it’ll be popular soon.

The big reasons why it isn’t practical are already highlighted in your post. Cost and alignment.

Who is going to realistically want to spend the time carefully and accurately parking their car so it’s aligned to the mm for a wireless charger for maximum efficiency. It would just be quicker and easier to park like a normal person and just plug it in.

 

[Jez]

Isn't electric £ per mile supposed to be 1/3rd of petrol/diesel?

Therefore losing 1% isn't a massive loss in comparison of cost. But in terms of if the whole country was doing it then yeah. The greta thunberg's of this world would never let it happen.

Yeah, i was more meaning a pointless loss and multiplied over millions of cars and billions of miles driven, thats an absolutely massive waste of money and power...

 

[bimbleuk]

I want to establish if the numbers make sense ... as ever, the true cost of running cars is often masked, in spades so, for the ev revolution, with congestion/eco charge factors;
you can pay up for a PCP, offsetting the risk, in exchange for some additional cash, but, so far, have purchased directly.

Currently wedded to the estate, or hatchback practicality, so, I'm not enthousiastic about the design of most of the current offerings : Kona doesn't seem bad,
but "...who's that , the next cargirl " , I'd missed that VW seem to be talking about an ID 3 variant
https://www.thisismoney.co.uk/money...lectric-family-estate-car-promising-2021.html

How about the Model Y with it's 7 seat capacity and is already being driven and tested in the US. Production may be an issue I guess until the German factory comes online for the EU.

I'm looking forward to my Octopus Go tariff switch so I can charge my ~50kw battery at home for £2.50-£3.00 + standing charge.

I'm well aware you don't buy a £40k car to save money but the low running costs makes it via for me to afford a nice car for a change.

 

[bimbleuk]

Yeah, i was more meaning a pointless loss and multiplied over millions of cars and billions of miles driven, thats an absolutely massive waste of money and power...

Sorry are we talking about ICE cars now because they sure do suck at 20-40% efficiency

 

[Matthew.M]

How can it be misinformation? Lets take your figures then, you quote high 90% efficiency so for a 100kW charger for say 95% efficiency you are still losing 5kW! For a 7kW home charger it may be manageable but fast charging seems a long way off even for 99% efficiencies. For your current gen 85% your home charger will still be losing 1kW! This is wasted energy and heat

There are articles around quoting 97% efficiency. And using a cable isn't 100%, the cables heat up due to the resistance. What's the efficiency of a standard 5m type 2 cable? I don't know, but when charging at 32A mine gets noticeably warmer than ambient.

My point is efficiency isn't the barrier for wireless charging. Cost and practicality are. Everyone assumes you'll be dumping kw's of heat but that just isn't true anymore.

The alignment isn't a huge issue, it guides you in on the computer and probably can even park itself.

I was mainly responding to efficiency point.

 

[Bear]

Everyone assumes you'll be dumping kw's of heat but that just isn't true anymore.

The alignment isn't a huge issue, it guides you in on the computer and probably can even park itself.

I was mainly responding to efficiency point.

So where does this missing energy disappear to? I'm not disputing it's not possible because it is. There are buses that are being charged using a 75kW wireless charger at 94% efficiency. That is 4.5kW lost in the system somewhere, this is basic maths and not up for arguement, where does this lost energy go if it isn't heat and lost radiated electrical field?

 

[Fusion]

There will be losses in a cable anyway. Plus, the motors aren’t 100% efficient- nothing is, if anyone’s up on their thermodynamics.

Seems a bit of a moot point when there are massive inefficiencies in petrol and diesel tech that we all gloss over.

 

[Russinating]

Isn't electric £ per mile supposed to be 1/3rd of petrol/diesel?

Therefore losing 1% isn't a massive loss in comparison of cost. But in terms of if the whole country was doing it then yeah. The greta thunberg's of this world would never let it happen.

Mine will be 1/10th (based on overnight 5p/kWh rate and current diesel 42MPG).