Perhaps Battery Powered Motorhomes.....

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.......are more realistic and closer than hitherto assumed?
This BBC summary of an interesting theoretical study by Björn Nykvist and Olle Olsson and published in 'Joule' is well worth a read:

BBC News - Climate change: Electric trucks 'can compete with diesel ones'

If you would like to read the article in 'Joule' it can be found here but there's a charge to access the full paper:

The Feasibility of Heavy Battery Powered Electric Trucks


Colin 🙂🙂🙂
 
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GeoffL

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Pity there's a charge to read that. However, assessment from first principles suggests that the claim is false with regard to current working practices and regulations; at least with regard to long-haul logistics and rechargeable batteries.

AFAICT, artics have fuel tank capacities between 500 and 1,500 litres. More importantly, a search of the 'net suggests fuel consumption of around 8mpg for today's most frugal. Some further searching shows an example EV (Tesla Model S) having an effective range of about 330 miles from a 90kWh battery pack (Tesla claim 370 miles). This is less than half the range I get from the 80 litre tank of my car. I'll take that as a yard stick to get an equivalent electrical energy per litre of fuel. 1kWh gives 330/90 = 3.67 miles and 1 litre of diesel gives about 660/80 = 8.25 miles. Hence 1kW is equivalent to 3.67/8.25 = 0.44 litres of diesel. So a 500 litres of diesel would be equivalent to 500/0.44 = 1,135 kWh and 1,500 litres to 1,500/0.44 = 3,410 kWh. A Tesla supercharger maxes out at 120kW, so it would take about 10 hours to supply the equivalent charge to 500 litres of diesel and 30 hours to supply the equivalent of 1,500 litres.

500 litres of diesel is about 110 gallons of fuel, which at 8mpg would give a range of 880 miles. This is equivalent to a 1,135kWh battery, which would take about 10 hours to recharge. So if a lorry always returned to base, the energy used during the working day could be replenished overnight. However, current long haul practice isn't to return to base each night (think how many lorries overnight at the roadside) and so it would require a network of roadside lorry charging points before these vehicles could become viable for long haul.

Now to payload: The 90kWh battery pack of a Tesla Model S weighs 540kg. So the equivalent of 500 litres of diesel would weigh 540 * 1135 / 90 = 6.75 tonnes and 1,500 litre equivalent would weigh over 20 tonnes (about half the payload of a diesel artic). I couldn't get proper data, but I suspect that a diesel engine and gearbox will weigh about half a tonne more than the electric equivalents, but that small offset isn't going to make enough different to restore the lost payload from going electric.

However, there might be light at the end of that tunnel in the form of aluminium/air batteries. These are non-rechargeable but can be designed to have quickly replaceable anodes and electrolyte -- items that can be replaced in the same order of time it takes to refuel a diesel-fuelled lorry. However, it's a catch-22 situation since this requires dedicated exchange stations, which requires both a standard be adopted and the infrastructure to be pre-built before the technology will be viable...

 

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Thanks for your input, Geoff - the points you make are very interesting.
I think that the authors are pointing out that an alternative to conventional logistics thinking would make heavy electric vehicles a serious possibility, even with technology that is currently on the horizon. They accept that appropriate technology, infrastructure and changes to the ways we organise payloads would be required. This is the very beginning of the move away from a fossil fuel to renewables economy and we need open minds if the much-needed changes are to be realised.
The change to electric vehicles generally will require us to accept change in the way we do things; personal cars, heavy goods vehicles (and motorhomes!) will need to be adapted and used in ways we are yet to fully understand.
The change from fossil to renewable fuels is akin to a step change in technology, and in my view such step changes are always an opportunity, not a threat. But then again, I'm a glass half full kind of person.
We have a very interesting, exciting - and no doubt challenging - time ahead of us!

Colin :):):)
 
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GeoffL

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Thanks Colin. This move towards EVs no matter what the consequences just seems insane to me. I can show mathematically that anthropogenic CO2 does not significantly affect global temperatures with nothing more than A-level maths applied to IPCC/NOAA fundamental values. Studies at Bristol University et al. have shown local pollution from EVs to be at least as bad, and sometimes worse, than for equivalent Euro 6 vehicles -- and that's without the pollution created remotely while generating the electricity to recharge them. Also, there are safety concerns over EVs as they can spontaneously burst into flames hours and/or days after being involved in an RTC and there have been several instances where EVs have ignited in towing companies' pounds. Special, often vehicle-specific, procedures are required to deal with fires in these vehicles -- procedures that manufacturers have been slow to produce.

So, AFAICT, there is nothing to be gained, and much to lose, from a premature move to EVs, which appears to me to be change for change's sake rather than something that might actually be of benefit. There might be upcoming technology (e.g. metal/air batteries) to challenge petroleum in the future and sufficient petroleum reserves to have the time to permit development of those technologies rather than rush into something that is worse than the status quo.
 

GeoffL

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Its not just about global warming its about peoples health and the right to breath clean air
Exactly. As I wrote previously, EVs produce more pollution locally than equivalent Euro-6 petrol and diesel powered vehicles. Very little comes out of the exhausts of Euro-6 ICEVs other than water and CO2 -- neither of which is a pollutant. The majority of pollution thus is particulates that come from tyre, road and brake wear, which EVs (being heavier, due to the weight of their batteries) produce more of. When it comes to lorries, it's no contest -- the massive additional mass of battery powered lorries guarantees they'll create significantly more pollution than the latest diesels.
 

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Exactly. As I wrote previously, EVs produce more pollution locally than equivalent Euro-6 petrol and diesel powered vehicles. Very little comes out of the exhausts of Euro-6 ICEVs other than water and CO2 -- neither of which is a pollutant. The majority of pollution thus is particulates that come from tyre, road and brake wear, which EVs (being heavier, due to the weight of their batteries) produce more of. When it comes to lorries, it's no contest -- the massive additional mass of battery powered lorries guarantees they'll create significantly more pollution than the latest diesels.

Not all particulates are the same, though Geoff.
The particulates emitted from diesel engines (no matter what treatment systems are added to their exhaust) are different to the particulates from tyres, brakes etc.
The former are far, far smaller, chemically different and more damaging to human health and the environment generally than the dust-like particulates from the latter.
The main point that the paper I've highlighted brings to the discussion is that we shouldn't assume that heavy goods vehicles need huge batteries with the associated increase in vehicle mass. Nykvist and Olsson argue that more frequent, faster charging of smaller batteries should be considered a viable option.
My view is that the move away from fossil fuel to renewables is a positive one and, when the technology and infrastructure is more mature, I will embrace it.
My intention was to bring an alternative view to the debate about electric powered heavy goods vehicles and the possible impact on us motorhomers, rather than a debate about EVs per se.
I'll leave the discussion here. I hope it was of general interest.

Colin 🙂🙂🙂
 

GeoffL

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Not all particulates are the same, though Geoff.
The particulates emitted from diesel engines (no matter what treatment systems are added to their exhaust) are different to the particulates from tyres, brakes etc.
The former are far, far smaller, chemically different and more damaging to human health and the environment generally than the dust-like particulates from the latter.
The main point that the paper I've highlighted brings to the discussion is that we shouldn't assume that heavy goods vehicles need huge batteries with the associated increase in vehicle mass. Nykvist and Olsson argue that more frequent, faster charging of smaller batteries should be considered a viable option.
My view is that the move away from fossil fuel to renewables is a positive one and, when the technology and infrastructure is more mature, I will embrace it.
My intention was to bring an alternative view to the debate about electric powered heavy goods vehicles and the possible impact on us motorhomers, rather than a debate about EVs per se.
I'll leave the discussion here. I hope it was of general interest.

Colin 🙂🙂🙂
Thanks -- it is of interest. It's a pity I couldn't access that paper as it would have been good to comment on what was actually written rather than approaching this from first principles.

The couple of studies that I've seen state that filtration removes just about all particles from the exhaust. So what's left is that from tyres, road and brakes. From an IET article (clicky link):
IET article said:
“The latest generation of diesels, with particle filters on the exhaust, emit virtually nothing from the exhaust. So, if an electric vehicle is emitting as much in the way of wear emissions as a diesel vehicle, switching to electric is not going to make a lot of difference.”

Wear and tear is particularly acute in the case of lorries. However, it is a problem for all vehicles, be they petrol, diesel or electric, and regardless of whether they are private cars or public transport buses or trains.
If lorries are to be more frequently charged then drivers are going to need to spend more time sitting around waiting for their vehicles to get enough charge for the next bit of their journey -- which won't be efficient use of their time. I suspect this might be viable for short-haul (say, the last stage of delivery into an urban area) but not for long trips, where a lorry might cover over 200 miles without stopping. A 'pony express' model might work; one with marshalling yards where drivers switch prime movers -- but each switch would take time and thus eat into their working day. Again, inefficient use of time.

As I wrote, there are upcoming technologies (sorry to keep harping on about metal/air) with similar mass energy density and replenishment times as petroleum. I'm sure that there will be a viable alternative to fossil fuel within a couple of decades. I just don't thing that current batteries are it!
 

Minisorella

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I’ve never really believed that electric is the way to go for vehicles. It’s a very pedestrian solution to finding alternatives to petrol and diesel and one that’s riddled with pitfalls. Electricity production isn’t necessarily ‘green’, although the UK is better than most countries in that respect. Batteries are self-defeatingly heavy and cumbersome, very expensive and have far too short a lifespan. What will happen to all the discarded batteries? Currently, the cost of replacement batteries is a big proportion of the value of the car and the second-hand market will hit huge problems. I’m not even sure if battery manufacture is clean? Charging takes far too long and the range is a real problem.

I’ve long thought it’s time for scientists to exercise some of those well known cliches... blue skies thinking outside the box etc, etc. At the moment, they’re trying to make a silk purse from a sow’s ear. I’m out of cliches 😜
 

yorkslass

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Something i know nothing about, but has been spoken about for years....the viability of hydrogen as a fuel source. The one thing I am pretty sure about is that the new technologies won't be affordable for many, and public transport won't fill the gap.....bus companies only want to run routes that are financially viable, only to be expected when they need to make a profit. Perhaps we need a return to public ownership.
 

GeoffL

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FWIW, I've seen a few papers about hydrogen fuel. There are issues, not least being it's uneconomical to distribute and so supply to refuelling points would almost certainly need to be local (equivalent to each petrol station having it's own oil well).

Regarding affordability of new technologies; BEVs will almost kill the second-hand car market. This is because the battery pack has a limited life (5 to 10 years) and is probably the most expensive part of the car. I have to ask whether I'd want to buy a car that would likely need a new engine within the next year and then ask whether I'd want to buy a 5 year old EV likely to soon need a new battery pack. Of course, this is good for the manufacturers since their product has guaranteed obsolescence and so an almost guaranteed market into which to supply replacements.

BTW, if anyone's interested, the link I gave upthread (clicky link) has links to other IET articles on similar subjects, including a summary of the study referenced in the OP (clicky link). The study makes a lot of "if ... then" observations AFAICT. For example, if a large network of fast chargers were to exist to service electric cars then trucks could use these to get by with smaller batteries.

It's an interesting subject for sure...
 

johnjjl

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Would you buy a second hand electric car/van, not knowing the remaining life span of the batteries? What is the mileage/life of, say the batteries in a Nissan Leaf? How much is a replacement bank? How much to dispose of the old set? I have just sold my Honda civic diesel with 168k miles on the clock,. 11 years old, engine still performing as if it were new!
 

trevskoda

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FWIW, I've seen a few papers about hydrogen fuel. There are issues, not least being it's uneconomical to distribute and so supply to refuelling points would almost certainly need to be local (equivalent to each petrol station having it's own oil well).

Regarding affordability of new technologies; BEVs will almost kill the second-hand car market. This is because the battery pack has a limited life (5 to 10 years)
Not true, vw have being doing feed back rests and they now say they will outlive the life of the car, 20 plus years at least, my mates VW is over 5 years and the battery is still 100%.
 

Bailey62

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.......are more realistic and closer than hitherto assumed?
This BBC summary of an interesting theoretical study by Björn Nykvist and Olle Olsson and published in 'Joule' is well worth a read:

BBC News - Climate change: Electric trucks 'can compete with diesel ones'

If you would like to read the article in 'Joule' it can be found here but there's a charge to access the full paper:

The Feasibility of Heavy Battery Powered Electric Trucks


Colin 🙂🙂🙂
Hi I can add a little perspective to the discussion as I have driven a Tesla model S for the last five years. Firstly driving habits change, with liquid fuels you run until nearly empty then refuel, with EV you always start with a full tank. EV”a are criticised over range, “Tesla claim 370 but actually only achieve 330 miles” this is true but do we believe claims about mpg? Liquid fuel cars have a longer range per tank, true but surely we would expect to stop after a couple of hundred miles in any event? I know my bladder usually suggests this. The Tesla can recharge quicker than I can discharge and have a coffee. As for cost I get free electric at super chargers but even at home can refuel for less than £10 I also have an old fashioned piston driven car but it costs over £50 for the same range.

I could go on but I firmly believe EV’s are a large part of the future but not in every case. My other vehicle is a Land Rover which I drive over mountains etc essentially “off grid”. Battery power is not likely to be good for that any time soon. Horses for courses comes to mind. Motor homes could easily be viable if charge points were added to other service facilities such as waste disposal etc.
 

GeoffL

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To my comment, "Regarding affordability of new technologies; BEVs will almost kill the second-hand car market. This is because the battery pack has a limited life (5 to 10 years)":
Not true, vw have being doing feed back rests and they now say they will outlive the life of the car, 20 plus years at least, my mates VW is over 5 years and the battery is still 100%.
I have to ask whether VW actually have 20 years of data for current batteries to be able to make that claim. A little research shows that the VW claim is actually that "batteries will retain 70 percent of their original capacity for 8 years or 100,000 miles." Industry standard seems to be 80%, not the 70% that VW have chosen. Also, ICEVs last a lot longer than the 8 years that VW cite as the lifetime of their EVs.

A little research suggests that Lithium Ion cells have a lifespan of between 500 and 800 charge/discharge cycles before the capacity drops below 80% of new, while Lithium Phosphate this is for up to 2000 cycles. As @Bailey62 wrote, EV owners always start with a 'full tank' -- i.e. they tend to charge after every day the car is used. So a daily driver will be subject to over 250 cycles a year, which will mean a Lithium Ion pack will have reached its theoretical end of life in a little over three years while a Lithium Phosphate pack this will be 8 years. While there are ways to extend battery life (such as not recharging unless it's really, really needed), I suspect the only way that EV owners will see 20 years of use from a battery pack will be to accept an increasingly reducing range.
 

johnjjl

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To my comment, "Regarding affordability of new technologies; BEVs will almost kill the second-hand car market. This is because the battery pack has a limited life (5 to 10 years)":

I have to ask whether VW actually have 20 years of data for current batteries to be able to make that claim. A little research shows that the VW claim is actually that "batteries will retain 70 percent of their original capacity for 8 years or 100,000 miles." Industry standard seems to be 80%, not the 70% that VW have chosen. Also, ICEVs last a lot longer than the 8 years that VW cite as the lifetime of their EVs.

A little research suggests that Lithium Ion cells have a lifespan of between 500 and 800 charge/discharge cycles before the capacity drops below 80% of new, while Lithium Phosphate this is for up to 2000 cycles. As @Bailey62 wrote, EV owners always start with a 'full tank' -- i.e. they tend to charge after every day the car is used. So a daily driver will be subject to over 250 cycles a year, which will mean a Lithium Ion pack will have reached its theoretical end of life in a little over three years while a Lithium Phosphate pack this will be 8 years. While there are ways to extend battery life (such as not recharging unless it's really, really needed), I suspect the only way that EV owners will see 20 years of use from a battery pack will be to accept an increasingly reducing range.
has there been any info replacement costs?(and disposal costs)
 

johnjjl

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Hi I can add a little perspective to the discussion as I have driven a Tesla model S for the last five years. Firstly driving habits change, with liquid fuels you run until nearly empty then refuel, with EV you always start with a full tank. EV”a are criticised over range, “Tesla claim 370 but actually only achieve 330 miles” this is true but do we believe claims about mpg? Liquid fuel cars have a longer range per tank, true but surely we would expect to stop after a couple of hundred miles in any event? I know my bladder usually suggests this. The Tesla can recharge quicker than I can discharge and have a coffee. As for cost I get free electric at super chargers but even at home can refuel for less than £10 I also have an old fashioned piston driven car but it costs over £50 for the same range.

I could go on but I firmly believe EV’s are a large part of the future but not in every case. My other vehicle is a Land Rover which I drive over mountains etc essentially “off grid”. Battery power is not likely to be good for that any time soon. Horses for courses comes to mind. Motor homes could easily be viable if charge points were added to other service facilities such as waste disposal etc.
Hypothesis. If you drove your Tesla to say, Heathrow, left it on a car park with no charging facilities at 10% charge left, for a month, what would be the state of the batteries on your return?
 
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