The EV fact thread

[ChipChop]

Also:

For my smaller 74kWh battery, the predicted range for a 100% charge is 282 miles.

Again, these are my 'Real life' figures.

What would the range be if I switched off all the heaters, and put the car in 'Eco' drive mode? No idea, this isn't my real life..... it's just as hypothetical for me as asking what would the remaining mileage be if I was towing a caravan - I don't know.

217 miles is indeed 77% of 282 miles. Real life?

 

[markjay]

217 miles is indeed 77% of 282 miles. Real life?

By 'Real life' I meant that to say this how I use the car, as opposed to the various hypothetical driving conditions that are often mentioned here.

As for the accuracy of the figures showing on the onboard computer- distance, consumption, and time - I already commented that for the purpose of this discussion, I am happy to accept them, the issue isn't important enough for me to engage in carefully controlled scientific testing (whatever is the EV equivalent of ICE ' brim-to-brim'). So yes, if (say) the car's mileage reading is incorrect for example, then the range calculation will be incorrect as well.

BTW, l am referring at the post previous to the one you quoted. In any event both screens agree (if you make the adjustment between the 74kWh battery and the 77kWh battery)

 

[ChipChop]

By 'Real life' I meant that to say this how I use the car, as opposed to the various hypothetical driving conditions that are often mentioned here.

As for the accuracy of the figures showing on the onboard computer- distance, consumption, and time - I already commented that for the purpose of this discussion, I am happy to accept them, the issue isn't important enough for me to engage in carefully controlled scientific testing (whatever is the EV equivalent of ICE ' brim-to-brim'). So yes, if (say) the car's mileage reading is incorrect for example, then the range calculation will be incorrect as well.

BTW, l am referring at the post previous to the one you quoted. In any event both screens agree (if you make the adjustment between the 74kWh battery and the 77kWh battery)

On the face of it the range figures appear to be no more sophisticated than the ones you would get from a 'trip computer' in a 1990's car. A simple percentage calculation.



What is the stated range from new of your Hyundai? 300 miles?

 

[markjay]

....What is the stated range from new of your Hyundai? 300 miles?

285 miles for my car with the higer trim spec and smaller 74kWh battery.

From memory, the lower-spec model (less weight, narrower tyres, etc) had a WLTP range of 300 miles with the same battery.

 

[Bellow]

Hands up who personally drives a low cost, super light, super small footprint, super efficient, city car - regardless of drivetrain - as their primary vehicle for themself.

So cars like Smart Fortwo, Smart ForFour, Renault Twingo, Volkswagen Up!, Suzuki Ignis, Citroen C1, Renault Twizy, Mitsubishi iMIEV, kei cars, etc.

Me. I ran a smart fortwo bought at 6 months old in 2005 for 14 years. No one copied me.
Initially bought as a stop gap while my foot injury healed (fortwo was the easiest way to a 2-pedal car without going much larger), temporary became 14 years. Probably wouldn't have endured without chassis mods - the understeer as standard is pitiful - it ended up agile and grippy.

 

[BTB 500]

Will be interesting to see the rebuttal to this.

Well, I would suggest that a single BEV matching fuel cell range / cost doesn't support the general statement made that hydrogen FCVs are more expensive than BEVs.

 

[markjay]

Well, I would suggest that a single BEV matching fuel cell range / cost doesn't support the general statement made that hydrogen FCVs are more expensive than BEVs.

I don't doubt the advantages of Hydrogen FC cars, however I think it would be odd to have a future where almost everything is electric apart for cars.

Given that (almost) every household in the West is connected to the grid, upgrading the grid's capacity seems like the logical step, instead of building a parallel infrastructure of Hydrogen distribution.

We should keep in mind that cars were first introduced in the last ninetieth century, and petrol station started appearing a decade or two later, at a time when houses did not have electricity.

 

[BTB 500]

Everyone knows that the real world range is half of that, and in winter it halves again.

Fuel cell range is certainly much less affected by cold weather. Efficiency drops a lot less than battery efficiency, and you get to heat the car for 'free' rather than having to consume additional power from the battery to do it. WLTP range is tested at 23C without any heating.

 

[Bobby Dazzler]

Me. I ran a smart fortwo bought at 6 months old in 2005 for 14 years. No one copied me.
Initially bought as a stop gap while my foot injury healed (fortwo was the easiest way to a 2-pedal car without going much larger), temporary became 14 years. Probably wouldn't have endured without chassis mods - the understeer as standard is pitiful - it ended up agile and grippy.

I had you in mind when I posted

 

[markjay]

Fuel cell range is certainly much less affected by cold weather. Efficiency drops a lot less than battery efficiency, and you get to heat the car for 'free' rather than having to consume additional power from the battery to do it. WLTP range is tested at 23C without any heating.

Agreed, but as per my previous post, there's already electricity in (almost) every house and (almost) every street in the UK.... do the advantages of fuel cell technology justify the building of a nationwide Hydrogen distribution infrastructure?

As others have said, I too believe that Hydrogen Fuel Cell will remain in the realm of commercial applications where vehicles are being refuelling at the depot (or bus garage etc) at the end of the journey or the days work.

 

[Bobby Dazzler]

Fuel cell range is certainly much less affected by cold weather. Efficiency drops a lot less than battery efficiency, and you get to heat the car for 'free' rather than having to consume additional power from the battery to do it. WLTP range is tested at 23C without any heating.

I’m sure that’s the case. The reality is that all fuel types are less efficient in cold weather - partly down to science and partly because of the way we use them to make ourselves more comfortable, ie heated seats, heating, aircon (to dehumidify), lights - they all consume some energy.

The other way of looking a “free heat” is wasted energy, and an EV wastes less. Some of the energy wasted as heat in non-EV vehicles is harvested and used for cabin heating, the rest, and the rest of the time it’s just good old fashioned wasted energy. An EV doesn my waste it, so it has to convert the energy to heat purposefully hence reduction in range.

 

[Bobby Dazzler]

For those concerned about the viability of EVs without being propped up with Government subsidies, what’s the position regarding public transport, should we pull subsidies there too?

 

[BTB 500]

I don't doubt the advantages of Hydrogen FC cars, however I think it would be odd to have a future where almost everything is electric apart for cars.

Given that (almost) every household in the West is connected to the grid, upgrading the grid's capacity seems like the logical step, instead of building a parallel infrastructure of Hydrogen distribution.

We should keep in mind that cars were first introduced in the last ninetieth century, and petrol station started appearing a decade or two later, at a time when houses did not have electricity.

Agreed, but as per my previous post, there's already electricity in (almost) every house and (almost) every street in the UK.... do the advantages of fuel cell technology justify the building of a nationwide Hydrogen distribution infrastructure?

As others have said, I believe that Hydrogen Fuel Cell will remain in the realm of commercial applications where vehicles are being refuelling at the depot (or bus garage etc).

To be clear I don't think fuel cell cars are perfect or necessarily 'the future'. I'm just seeking to correct some of the statements being made about them.

As mentioned it looks extremely likely that we'll need a hydrogen infrastructure to enable support zero emission HGV and van usage that isn't fixed-route 'depot' based (battery technology could work for a good proportion of that). Once there's a hydrogen infrastructure then fuel cell becomes a practical option for car drivers who want/need longer range and faster refuelling. That's why Toyota/Hyundai/BMW/Vauxhall/Ford/JLR/Honda/etc. are sinking large amounts of money into this technology now.

BEV will remain a practical solution for much (most?) of the personal transportation sector.

 

[BTB 500]

The other way of looking a “free heat” is wasted energy, and an EV wastes less. Some of the energy wasted as heat in non-EV vehicles is harvested and used for cabin heating, the rest, and the rest of the time it’s just good old fashioned wasted energy. An EV doesn my waste it, so it has to convert the energy to heat purposefully hence reduction in range.

An EV also wastes energy during every charge of course (20% ballpark figure).

From a purely practical POV the fact remains that EV range is far more affected by cold weather than any other power source, which can be an issue for some people.

 

[Bobby Dazzler]

An EV also wastes energy during every charge of course (20% ballpark figure).

From a purely practical POV the fact remains that EV range is far more affected by cold weather than any other power source, which can be an issue for some people.

All machines (ie the motor, transmission, etc) and all (man made) systems (ie the end to end ecosystem surrounding that machine like manufacturing, energy production, transmission/transit, and storage) waste energy. There are few perfect systems, the universe is the only one which springs to mind.

In an energy-aware and resource-constrained world then the least-waste option must be preferable. That said it’s not viable for everything to be the least-waste and so there will always be a range of efficiencies, the key is to choose the least-waste option when it’s possible and viable to do so.

The range of EVs are definitely more affected by cold weather driving - for scientific and usage reasons - it’s often stated on this thread, and I don’t recall anyone anyone suggesting that it’s not the case. The difference of opinion usually comes from the perception of how impactful that is.

 

[Bellow]

Given that (almost) every household in the West is connected to the grid, upgrading the grid's capacity seems like the logical step, instead of building a parallel infrastructure of Hydrogen distribution.

Upgrading frequently means complete replacement. It just goes back in the same hole.

Agreed, but as per my previous post, there's already electricity in (almost) every house and (almost) every street in the UK.... do the advantages of fuel cell technology justify the building of a nationwide Hydrogen distribution infrastructure?

But not necessarily accessible by EVs.

 

[Dryce]

For those concerned about the viability of EVs without being propped up with Government subsidies, what’s the position regarding public transport, should we pull subsidies there too?

Maybe it's an issue of directing subsidies.

As an example it seems to be assumed that the public money pumped into railways is good value. I'm not convinced. Despite subsidies peak fares and walk on fares are high on the railways meaning that those using them for work / commuting are being hit both with the subsidy from their taxes and the gouging on pricing.

We have a lot of road freight. It may be that some decent public investment in radical management of it could improve roads generally and improve emissions.

And there's a fundamental question that bothers me: Why are our urban buses so cr*p. When I was young a bus going through a city would bang and crash and rattle and jolt because of the way it was constructed/fitted out and the the way it interacted with the nearside part of the road. Why is it when I ride in a modern EV bus that it is just as bad in terms of crash bang rattle jolt as several decades ago? Why are the seats just as cramped and bad?
.

 

[PXW]

An EV also wastes energy during every charge of course (20% ballpark figure).

From a purely practical POV the fact remains that EV range is far more affected by cold weather than any other power source, which can be an issue for some people.

I’m interested in this 20% figure, which I think you have used a few times. Collective wisdom on the Tesla forums (where widely used apps such as Teslafi give some fleet-wide data) seems to indicate that AC charging is around 87% efficient and DC charging more like 97-99%. Obviously vehicles and BMS can vary, but from my reading the 20% would be an outlier low number rather than typical.

Of course if we then look at the overall efficiency of conversion of onboard “fuel” to forward motion then the EV is massively ahead of any ICE…

 

[190]

For those concerned about the viability of EVs without being propped up with Government subsidies, what’s the position regarding public transport, should we pull subsidies there too?

For the railways and underground yes we should pull subsidies, because the only way the unions have been able to take the pi$$ to the extent they have got away with is practically unlimited public funding. No fully private company would pay drivers such high salaries. They are being paid more than airline pilots for a skill set comparison that is laughable. In fact a private company wouldn't even have drivers on the underground, it would have been automated by now as it has been in other countries. I'd be more than happy for subsidies to fund efficiently run public transport but how do we get there for the railways and underground when the unions have no interest in efficiency ?

 

[Bellow]

To be clear I don't think fuel cell cars are perfect or necessarily 'the future'. I'm just seeking to correct some of the statements being made about them.

Indeed - and you're winning me over to a more favourable view of FCs.

As mentioned it looks extremely likely that we'll need a hydrogen infrastructure to enable support zero emission HGV and van usage that isn't fixed-route 'depot' based (battery technology could work for a good proportion of that). Once there's a hydrogen infrastructure then fuel cell becomes a practical option for car drivers who want/need longer range and faster refuelling. That's why Toyota/Hyundai/BMW/Vauxhall/Ford/JLR/Honda/etc. are sinking large amounts of money into this technology now.

But what I cannot get my head around is storage. Somewhere between production and end use, it has to be stored - and in large quantities. By what method? The highest of pressures won't be an option (pressure vessel geometry and scale) and at lower pressure it is incredibly bulky. It also loves to leak and of all the gasses I can think of its flammability limits are enormous - making it a massive explosion risk.
Cryogenic storage removes the pressure requirement but at what energy cost in refrigerating it down to minus 253C and what safeguards are needed to counter any loss of that refrigeration? Pressurised storage also extracts a significant energy penalty in compressing it to high pressure.