EV range

JKenH

Grumpy_chap said:

JKenH said:

As to the efficiency losses I am always amazed that EV enthusiasts suffer only minimal charging losses whereas the professionals who set out to measure charging losses scientifically find the figures are much higher.

If EVs suffer 10-15% charging losses then anyone budgeting/comparing costs needs to know the true cost per mile which one has to take into account actual miles travelled /kWh from the battery and charging inefficiencies.

It isn’t made clear just what the dashboard shown consumption does actually include on an EV. It may or may not include battery preconditioning, preconditioning the cabin, non driving consumption (HVAC), monitoring programs and just general loss of charge over time when the car isn’t being used. 

The lowest (56%) efficiency was during winter with a long 
stand still and probably several cases of preheating the cabin before 
driving. 

AIUI, charging losses and vampire drain are two different factors.

Charging losses are definitely the difference between energy drawn from the electricity meter through the charger and the difference to what actually gets stored in the car's battery.

Vampire losses are a different thing.  I actually asked up thread what these vampire losses are and why they are significant on an EV but not an ICE. 

If I take an ICE to the airport and leave it for two week, the alarm, clock, etc will have been active in that time but the teeny 12V battery will have enough charge to start the car engine.  It's only if there is a fault somewhere that the power sapping over two weeks would be noticed by the driver.

With EV, the reported power drain is something apparently far higher.  There could be some loss of battery holding the charge.  But it does seem as though a lot of this "vampire drain" is features that the EV offers but are not directly to do with the operation of the car. 
 - Enhanced security with a suite of cameras recording all directions all the time. Possible with an EV, impractical with an ICE.
 - Cabin heating when it is cold weather ahead of getting in to drive away.  I think this is common for EV's to heat while parked, so using mains power rather than reducing the vehicle range in driving.  Controlled by an app.  I guess an ICE could also have similar, I even think some higher-end ICEs do have this type of feature.  For some reason, with an EV, the power used is a massive amount but the ICE running the engine while stationary to heat the cabin is no issue.
 - What else?

Comparisons about EV / ICE "vampire drain" should be on a like-for-like consideration.  I can also see that is not always as easy as it sounds - particularly the cabin heating and whether convenience changes behaviour.  With my ICE, I start and drive and the interior soon warms up.  With an EV, plugged in and app control, I think I would use the feature to warm the interior before departure.  Nothing is as simple as it seems.

Yes, charging losses and vampire drain are two different things but both reduce the range (miles that can be driven) you will get from the kWh that come from the plug. 

I found this article on vampire drain interesting. 

https://www.recurrentauto.com/research/tesla-vampire-drain

Something I hadn’t considered is the change in battery energy levels as temperatures change. Usually in the UK a battery will cool rather than heat up if left overnight (except perhaps last July). Does this affect the amount of available energy in the battery?

Petriix

JKenH said:

Does this affect the amount of available energy in the battery?

I believe the cold temperature limits the amount of energy that can safely be extracted from the battery rather than what it can store in total.

It's obviously different for everyone depending on their own circumstances but I frequently used to drive half a mile in the wrong direction to fill up with diesel at the cheapest local price before a long journey.

On the other hand I was happy to accommodate adding a 10 minutes each way walk to the gym while getting a free charge at Lidl. It's not exactly a waste when it's free, but certainly a compromise.

Yes, EVs are potentially problematic for anyone without reliable, affordable charging. We all know that and no one is arguing against that point. 

Grumpy_chap

JKenH said:

Yes, charging losses and vampire drain are two different things but both reduce the range (miles that can be driven) you will get from the kWh that come from the plug. 

I suppose charging losses simply don't exist for an ICE in the same way as they do for an EV, in so far as everything dispensed from the fuel nozzle ordinarily reaches the fuel tank where as the energy into the charge system doe snot all reach the battery.

As for "vampire drain" or "non-motive energy", in an ICE the inefficiencies are so high that running the car on the drive for a few minutes to warm the cabin is essentially unnoticeable.  The EV, on the other hand, is so much more efficient that the pre-heating the cabin is a significant delta to the overall efficiency of the vehicle.

In the long term, highlighting the charging losses is the only way for minds to be concentrated on minimising the charging losses.

Herzlos

JKenH said:

Herzlos said:

jimbo6977 said:

Jenni_D said:

jimbo6977 said:

regarding charging losses, if a petrol pump was sending only 85-95% of the recorded amount of petrol to customers' tanks the station would be shut down and the owner prosecuted. but in EV world this is all tickety-boo it seems. 

🙄

Another pointless whataboutery. How much energy is expended (lost) pumping the fuel? How much is lost getting the fuel to the filling station? How much is lost in producing the fuel? (And all this before we consider the energy transfer efficiency of an ICE engine).

it's not whataboutery, it's simple case of paying for quantity M of a product and receiving quantity M x 9/10

regardless of how the product got to the dispensing point, and what the customer does with the product afterwards, how is this acceptable?

How much petrol do people waste driving to petrol stations?

Electricity efficiency losses happen with every electrical device, it's just how it works and I can't really see it being a sticking point for anyone?

I fill my petrol car up when going to Asda or Morrisons for a shop or just occasionally when I drive past a petrol station on route. Because the car is capable of going around 500 miles a tank (almost a month’s worth of driving) I find I can fit a fill up in without going in a detour. At our local Asda the diversion to the pumps as you go in is no more than 10 yards.So, no, I don’t waste petrol driving to petrol stations and I doubt many others do either.

That wasn’t the case with my EV. While I would do most of my charging at home when I was on a long run I usually had to go on a detour to find a charger. In fact it often turned out to be several miles as my first choice charger rarely worked. In fact, advice given to me on the G&E MS board was to avoid motorways for charging - drive a mile or two off the motorway and the chance of finding a working charger are much better.

For anyone who doesn’t have home charging then the likelihood is they will waste even more electricity driving around looking for available working chargers.

But presumably most EV users will take the car to places that can charge, and charge whilst they are there anyway?

It doesn't work for road trips, but given the average car journey is 8 miles, and all modern EV's have at least 100 miles of range that means if they just need to stumble across a charger every 12th trip.

Assuming I had an EV with 100 miles range, my normal driving would mean I'd realistically only need to charge every week or so, and we're at a supermarket every other day where I could charge. Ditto if I worked from an office in the city, I could charge at the train station once a week, or at a park & ride twice a week.

My parents entire mileage could be covered by charging once a month at Asda. "Ah, but what if it takes over an hour to charge?" you say, but you've no idea how long my mum can spend in Asda in a single trip, it's incredible.

There will be some extreme cases where a car is only driven between locations without charging, but most destinations (shops, leisure, commuting) will have some charging facility. Those people may have to wait a while for suitable EVs, though EV's already exist with 400 mile ranges so they shouldn't have to wait forever.

MouldyOldDough

The government is banning the sale of new petrol and diesel cars in 2030. Have you thought how this will affect you? The ban will affect everybody including disabled motorists. The ban is less than eight years away so if you haven’t thought about it already now is the time to do so.

More and more electric vehicles are coming to market all the time and battery technology has come a long way since the first EVs hit the roads. You might have ruled out an EV in the past, but there might be something that now suits your needs. It’s worth doing some research as it will be something you will have to think about in the near future.

Over the past few years you will have read about several EV projects that DMUK has been involved in and the worrying news that the public charging infrastructure is completely inaccessible to many disabled motorists. It is thought that roughly 40% of households will not have the facilities and access at their home to have an at home charging point installed, so will be reliant on public charging infrastructure. With the fastest rapid charge taking at least 20 minutes, a big proportion of the populations will have to completely rethink refuelling - or what will be the new normal - re-charging! It won’t be a case of just popping to the local petrol station while running another errand or going to work, charging will be the reason for the journey. The way in which we think about getting fuel for our vehicles will completely change.

In April 2022 Disabled Motoring UK was awarded some funding from the National Lottery to research the worries and concerns which disabled motorist have regarding the ban on the sale of new petrol and diesel vehicles in 2030 and switch over to electric vehicles (EVs). The charity surveyed participants from May to September and received over 2000 responses.

Disabled Motorist identify the lack of a disabled parking bay as their biggest barrier to accessing public charging infrastructure.

The survey asked participants to rank in order from 1-6 what would pose the biggest difficulty to them when using public charge points. 1 being the biggest difficulty and 6 being the least. The options were:

·         Dexterity required to plug in cable to charger and car

·         Lack of an accessible parking bay

·         Height of machinery

·         Complexity of charging machinery and booking/payment apps

·         Machinery being on a plinth without a dropped kerb

·         Weight of charging plug and cable

The biggest problem was clear from the results with 41 % saying that the biggest difficulty would be a lack of a disabled parking bay. Most other results had equal weighting.

The other major concerns included the cost of purchase and the worry of charging on longer journeys.

45.7% of people ranked the cost of purchasing an EV as the thing that concerned them most with the worry of charging on longer journeys coming in at second most concerning at 12.5%.

EVs are becoming more widespread, but there is yet to be an established second-hand market for such vehicles. There is no clear understanding of resale values and second-hand EV reliability. This is off putting to all motorists wanting to make the switch especially with the cost of new EVs being so high.

DMUK Communications & Campaigns Director, said: “The ban on the sale of new petrol and diesel vehicles is moving closer and it is clear from the results of this survey that more needs to be done so that disabled motorists can move forward with this transition. Some of the problems highlighted in the survey aren’t unique to disabled motorists. The cost of purchase, the worry of charging on longer journey and availability of public charging will affect all motorists. However, the lack of accessible public charging is problematic. From the survey the biggest concern on public charging is the lack of a disabled parking bay. In recent BSI guidance issued on accessible public charging (PAS 1899) the provision of a disabled parking bay is just an annex to the document. Our survey suggests that this needs to be at the forefront of any guidance to make public charging truly accessible.”

Herzlos

Disability access is definitely a big thing that needs to be addressed, and I hope will catch up as demand is available. I'm assuming that most people who are too disabled to pump petrol will get a similar assistance with charging.
The biggest thing we seem to be missing is disabled charging spaces where there's sufficient room to get to the charger and charging port from a wheelchair, but that's at least an easy fix.

Motability have 47 full electric cars available to rent now, and 18 hybrids, so they don't seem overly concerned yet.

As I understand it, you want to stick to petrol because at a staffed petrol station you can stick your hazards on and someone will come out and pump for you? Why do you not think that'll be an option with a staffed EV charging station? I'm pretty confident all petrol stations will have fast chargers by 2030.

It's also worth noting that the ban is only on pure ICE vehicles; you'll still be able to buy a hybrid and never plug it in, until it starts getting hard to find a petrol pump.

MouldyOldDough said:

The ban is less than eight years away so if you haven’t thought about it already now is the time to do so.

Why? 8 years is a long time in cars. That's 2.66 motability lease periods, and at least 2 standard finance periods. Apparently the average length of a car ownership is 2 years, so 8 years is 4 cars away.

You'll also still be able to buy a petrol car the day before the ban, or buy a 2nd hand one, if you can find either. So realistically you may be able to get to about 2040 before you need to buy a dreaded battery car. I certainly have no idea what vehicle I'll need in 8 years time, never mind 20.

The biggest risk isn't the ban; it's the market and it's entirely possible you won't be able to buy a new ICE vehicle before 2030 as manufacturers have largely stopped selling and developing them, because most people want EVs.

MouldyOldDough

Changing the subject slightly. :

Exactly how does charging an EV at different rates work ?

I am aware (from schoolboy physics)  that V=I*R, or Charge Current = Voltage / Resistance But surely R (resistance) is obviously fixed.

So - do they ramp up the voltage to shorten charging times (by up to 10 times)

if not - how do they force a charge in to a Lithium battery at a higher rate than it usually accepts ?

The same question is for mobile phone fast chargers ..

MouldyOldDough

Herzlos said:

MouldyOldDough said:

The ban is less than eight years away so if you haven’t thought about it already now is the time to do so.

Why? 8 years is a long time in cars. That's 2.66 motability lease periods, and at least 2 standard finance periods. Apparently the average length of a car ownership is 2 years, so 8 years is 4 cars away.

I've had my 2017 car for 6 years and I should imagine that with the current state of finances, inflation and savings - there are many others in a similar position ?

Herzlos

MouldyOldDough said:

Herzlos said:

MouldyOldDough said:

The ban is less than eight years away so if you haven’t thought about it already now is the time to do so.

Why? 8 years is a long time in cars. That's 2.66 motability lease periods, and at least 2 standard finance periods. Apparently the average length of a car ownership is 2 years, so 8 years is 4 cars away.

I've had my 2017 car for 6 years and I should imagine that with the current state of finances, inflation and savings - there are many others in a similar position ?

Sure, some people may be looking to buy their last ever new petrol car, but given the average is just 2 years most people are nowhere near it yet.

That you've had yours for 6 years doesn't mean you're going to struggle to find a petrol car yet and be forced to use electric.

Honestly, it just sounds like yet another stretched reasoning to try and claim EV's are a problem.

Herzlos

MouldyOldDough said:

Changing the subject slightly. :

Exactly how does charging an EV at different rates work ?

I am aware (from schoolboy physics)  that V=I*R, or Charge Current = Voltage / Resistance But surely R (resistance) is obviously fixed.

So - do they ramp up the voltage to shorten charging times (by up to 10 times)

if not - how do they force a charge in to a Lithium battery at a higher rate than it usually accepts ?

The same question is for mobile phone fast chargers ..

Watts = Amps * Volts, so you'd either increase the current or voltage. For phone chargers over USB which are capped at 5v you'd obviously increase the amps, but for a car charger I assume you increase both.

Resistance isn't quite fixed, it's lower at higher voltages for reasons I'm not sure; IIRC that's why power lines transmit at huge voltages.