Adventures in an all electric vehicle.

[GRW]

Today I spent the day at an aerospace event. Battery planes are coming and so are hydrogen ones. They feel that the effort is going into air travel.
Oh and there will be hybrid planes using substitute fuels to get off the ground and batteries to make the flight.
Nice

Will they be able to carry any people or freight?


More seriously, commercial planes need to carry 50% more spare fuel than the journey requires (so that on the event of bad weather, diversions, delays etc - they don't fall out of the sky).
If a battery-powered airliner has to carry an extra 50% (usable) battery storage, that's an awful lot of weight.

 

[My Old Landy]

Will they be able to carry any people or freight?


More seriously, commercial planes need to carry 50% more spare fuel than the journey requires (so that on the event of bad weather, diversions, delays etc - they don't fall out of the sky).
If a battery-powered airliner has to carry an extra 50% (usable) battery storage, that's an awful lot of weight.

Some of the people I spoke to today were very convincing in their abilities to provide a solution. The fossil fuels will be legislated out across the globe for air travel. The thrust some of these new technology motors are making from an electric motor is phenomenal. The control systems are also very impressive. One company already had a prototype ready for air trials. It is coming and no amount of 'it will never work' is going to stop the tide!!

 

[GRW]

Nope. Wrong again.

I use mine for both local and 100+ mile trips (that is one way, with plenty of capacity for the return trip). A 480 mile trip to Scotland will not present any problem whatsoever. I do wonder what you are on - never really bothering to think, rationally, before posting.

The longest journey so far was 230 miles. The shorter return to home trip was started with about 12 miles predicted spare range - I did not bother to go a couple of miles ‘off route’ to top up and arrived home with that spare buffer. Not a problem for anyone who can use what they have in a sensible fashion - so quite easy to use a (suitable) EV for far more than just local commuting/shopping/etc.

If I had only wanted a vehicle for round trips of 50 miles, I would have bought one with a smaller battery. If I had wanted a vehicle for local load carrying, I would have got a van, not a car. I have fitted a tow hitch for my occasional trailer requirement. Horses for courses.

You could do a 480-mile trip to Scotland on a pushbike. That doesn't mean a bicycle is best suited for doing so.
EV's are better suited to commuting/shorter journeys than long distance. You can charge them from home base all the time (assuming you don't live in a flat or a terraced house with no off-road parking), & you get the artificially-created ULEZ zone advantages (plus the reduced emissions for the city folk), plus you can have a sensibly-sized EV that makes the best of the attributes of the tech.

(I wonder if someone will come out with the idea of a booster battery / range extender for the EV?
Need longer range for the weekend away? Tow a dinky Erde type trailer behind your EV, with an extra battery pack & an umbilical connection to extend the range of your EV)

 

[DanZac]

Will they be able to carry any people or freight?


More seriously, commercial planes need to carry 50% more spare fuel than the journey requires (so that on the event of bad weather, diversions, delays etc - they don't fall out of the sky).
If a battery-powered airliner has to carry an extra 50% (usable) battery storage, that's an awful lot of weight.

I'm not sure where 50% extra fuel comes from? As far as I'm aware it's an addiitional 5% of the trip fuel, plus sufficant to reach your diversion, plus a bit more.

I suppose that there could be situations where that could equal 50%, but I'm pretty certain that 50% isn't the norm.

What Are Minimum Fuel Requirements And How Are They Defined

The amount of fuel to be carried for a flight depends on local air regulations.

simpleflying.com

 

[premmington]

You could do a 480-mile trip to Scotland on a pushbike. That doesn't mean a bicycle is best suited for doing so.
EV's are better suited to commuting/shorter journeys than long distance. You can charge them from home base all the time (assuming you don't live in a flat or a terraced house with no off-road parking), & you get the artificially-created ULEZ zone advantages (plus the reduced emissions for the city folk), plus you can have a sensibly-sized EV that makes the best of the attributes of the tech.

(I wonder if someone will come out with the idea of a booster battery / range extender for the EV?
Need longer range for the weekend away? Tow a dinky Erde type trailer behind your EV, with an extra battery pack & an umbilical connection to extend the range of your EV)

Google "i3 Rex"

 

[truckdoctor]

You could do a 480-mile trip to Scotland on a pushbike. That doesn't mean a bicycle is best suited for doing so.
EV's are better suited to commuting/shorter journeys than long distance. You can charge them from home base all the time (assuming you don't live in a flat or a terraced house with no off-road parking), & you get the artificially-created ULEZ zone advantages (plus the reduced emissions for the city folk), plus you can have a sensibly-sized EV that makes the best of the attributes of the tech.

(I wonder if someone will come out with the idea of a booster battery / range extender for the EV?
Need longer range for the weekend away? Tow a dinky Erde type trailer behind your EV, with an extra battery pack & an umbilical connection to extend the range of your EV)

That's a very good solution, maybe hire one for the trip?

 

[brewdexta]

Here's some battery pack pricing https://www.secondlife-evbatteries.com/collections/ev-packs - following on from the cheap EV discussion earlier.

A 40kWh Leaf battery is £7.4k ex VAT- so just under £230 per kWh in VAT - but this is tested and ready to go back into an EV, not really targeted at second use home solar. You can get cheaper ex EV batteries for that.

To put that into context, the cheaper end of solar storage, apart from DIY cell builds, say Pylontech, are £850 inc VAT for 2.4kWh, so about £350 per kWh inc VAT, gets a bit cheaper if you buy the bigger batteries. https://www.tradesparky.com/solarsparky/batteries/pylon/pylontech-us2000c-24kw-battery. This is what I have, they have reduced £100 in the last couple of weeks.

The dearer end of Solar storage is say the Libbi from MyEnergy, which is 4.6k + VAT for 5kWh, but I think it gets a bit cheaper if you buy more modules. So about £1100 per kWh inc VAT. https://www.myenergi.com/libbi-battery-storage/

Tesla Powerwall is about 10K for 13.5kWh usable capacity installed, so about £1350 per kWh, probably plus VAT. Apart from the Tesla, all the above figures are gross capacities, not usable capacities as I can't be arrised to dig out the info

The solar batteries typically simply connect to your inverter if its the hybrid type. With an EV battery, a bit more jiggery pokery is needed to get your solar in and your mains out, I haven't looked into that too much yet, could be vehicle to grid/house, tear down and assemble cells into 48v packs, use a HV inverter etc. Then get the right BMS working. Something I would do in a small purpose built shed, well away from the house In truth I'll probably never do it until its a feature of a future EV,

 

[GRW]

Google "i3 Rex"

So.... a BMW with "Rex".... is an EV with a motorbike engine in the boot to recharge the batteries en route?

So, their advanced technology solution, is to create a small car version of the diesel-electric locomotive from the 1960's?

 

[DanZac]

Google "i3 Rex"

Can someone explain why it only extends the range by 90 miles?

Isn't it like a train where you just use the engine to drive an alternator to provide power to drive the wheel motors, in which case it should go on endlessly until you run out of fuel?

And more the point, why don't they just do that anyway? I guess using petrol to create electricity isn't that efficient?

 

[premmington]

So.... a BMW with "Rex".... is an EV with a motorbike engine in the boot to recharge the batteries en route?

So, their advanced technology solution, is to create a small car version of the diesel-electric locomotive from the 1960's?

Yes... But I think it is good solution (to a problem).

I know what you gonna say - why not just put a 1.0 three cylinder petrol in it - in the first place.

But a range extender does have obvious advantages.

 

[premmington]

Can someone explain why it only extends the range by 90 miles?

Isn't it like a train where you just use the engine to drive an alternator to provide power to drive the wheel motors, in which case it should go on endlessly until you run out of fuel?

And more the point, why don't they just do that anyway? I guess using petrol to create electricity isn't that efficient?

There are losses - plus the twin cylinder motorbike engine is just not big enough to generate enough power for the car on full power and it has tiny fuel tank - but you only get out what you put in - energy wise.


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The explanation off google

Yes it is possible, however the gasoline engine is only meant to maintain the battery once it gets to 7–10% of total capacity. This is no hybrid vehicle. Once the battery is drained to 7–15%, the gasoline engine will then turn on to maintain the battery level. It does not charge the battery back up. The fuel capacity is only about 2.1 gallons so the acceleration and performance will be normal until the battery gets to about 10% and then the car will start the struggle on hills and be limited to a lower top speed as the gasoline motor runs a generator that produces electricity to maintain the batteries. The gasoline generator is not meant to provide enough energy to provide peak electrical performance once the battery is near depletion. In summary, the gasoline generator will provide enough energy to power the vehicle once the battery is near empty but at a lower performance level.

 

[willie.macleod]

Can someone explain why it only extends the range by 90 miles?

Isn't it like a train where you just use the engine to drive an alternator to provide power to drive the wheel motors, in which case it should go on endlessly until you run out of fuel?

And more the point, why don't they just do that anyway? I guess using petrol to create electricity isn't that efficient?

They have a tiny fuel tank, less than 10 litres. That's why it only extends range by 90 miles. You can always refill it!

The i3 is a typical solution which looks good on paper and doesn't work well in the real world. Folk bought them with the idea that they would never get stuck, they never ended up using the REX and what happens if you don't use an engine for months/years at a time? They end up having all sorts of issues with the petrol engine.

I used to drive one on a 170 mile round trip every week. Could charge with a rapid charger at each end and there were chargers enroute as well so perfectly feasible to do it on full electric, I'd typically get to within the last mile of my destination and the REX would fire up, little petrol engine revving its heart out while I was stationary in town, just where you don't want emissions! The i3 is a great car for single track roads, nippy and handles well but I would forget the REX.

 

[GRW]

Yes... But I think it is good solution (to a problem).

I know what you gonna say - why not just put a 1.0 three cylinder petrol in it - in the first place.

But a range extender does have obvious advantages.

Seems a bit like having a "Reserve" fuel tap position on an older motorbike.
Seems rather daft to go to the expense and trouble to put basically a small petrol generator into an EV - but make it a weedy one so it can't actually charge the battery up.
So in effect, its an engine driven trickle-charger in the boot of an EV.
You couldn't make it up.

 

[premmington]

Seems a bit like having a "Reserve" fuel tap position on an older motorbike.
Seems rather daft to go to the expense and trouble to put basically a small petrol generator into an EV - but make it a weedy one so it can't actually charge the battery up.
So in effect, its an engine driven trickle-charger in the boot of an EV.
You couldn't make it up.

i3 with a new battery on warm day not up a mountain - has a range of 110miles ish.

The REX was seen as good idea at the the time - but the 34hp twin cylinder Kymco engine was just not suitable - so strangled with emissions compliance .

Same engine was fitted to the BMW C650 GT scooter rated at 59hp (only Euro 4 rated).

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I really did look into these at the time - these were the first EV's (bar a G Wiss) I had ever worked on.

 

[GRW]

i3 with a new battery on warm day not up a mountain - has a range of 110miles ish.

The REX was seen as good idea at the the time - but the 34hp twin cylinder Kymco engine was just not suitable - so strangled with emissions compliance .

Same engine was fitted to the BMW C650 GT scooter rated at 59hp (only Euro 4 rated).

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I really did look into these at the time - these were the first EV's (bar a G Wiss) I had ever worked on.

34hp, so pretty much a 25KW(M) engine. Surely that ought to be enough spuds to power a sizeable charger to charge the pack??

 

[premmington]

34hp, so pretty much a 25KW(M) engine. Surely that ought to be enough spuds to power a sizeable charger to charge the pack??

746w per HP - so near 25kw. But there are losses - lots of them - it is lot less that 746w in real life - taking heat/friction and other losses. 710w is the standard start point for many calcs...

But you now getting the feel for the losses in converting petrol to charged battery power - 34hp does not or did not "touch the sides" - the motor was taking more out than the Kymco engine could put in - so thus the reduced performance map to keep it all on the level.

 

[premmington]

They have a tiny fuel tank, less than 10 litres. That's why it only extends range by 90 miles. You can always refill it!

The i3 is a typical solution which looks good on paper and doesn't work well in the real world. Folk bought them with the idea that they would never get stuck, they never ended up using the REX and what happens if you don't use an engine for months/years at a time? They end up having all sorts of issues with the petrol engine.

I used to drive one on a 170 mile round trip every week. Could charge with a rapid charger at each end and there were chargers enroute as well so perfectly feasible to do it on full electric, I'd typically get to within the last mile of my destination and the REX would fire up, little petrol engine revving its heart out while I was stationary in town, just where you don't want emissions! The i3 is a great car for single track roads, nippy and handles well but I would forget the REX.

Agree with the bit in bold 100% - I even thought this was a good idea - I did...

 

[GRW]

710w per HP - so nearer 24kw.

But you now getting the feel for the losses in converting petrol to charged battery power - 34hp does not or did not "touch the sides" - the motor was taking more out than the Kymco engine could put in - so thus the reduced performance map to keep it all on the level.

I thought 1hp was 746 watts.
Either way, yes, I suppose the only way the engine could put more energy. IN, than the weight of car & battery & load took OUT.... would be if the car was pulled over & stopped for long enough.

Really poor solution all-around really. Kinda pointless.
I hope for the sake of humanity that hardly anyone was daft enough to buy one

 

[Agrismith]

If they where to look at range extenders surely interchangeable battery packs would be the best option. Have space for multiple batteries but can run on a single one. Reducing weight for normal travel. But the range is there and can swap out at a battery station in minutes to save waiting for charge. I am surprised the EU or similar haven't already drawn up a standardized battery design in case we go this route in the future,or maybe they have and it's not been publisized

 

[premmington]

If they where to look at range extenders surely interchangeable battery packs would be the best option. Have space for multiple batteries but can run on a single one. Reducing weight for normal travel. But the range is there and can swap out at a battery station in minutes to save waiting for charge. I am surprised the EU or similar haven't already drawn up a standardized battery design in case we go this route in the future,or maybe they have and it's not been publisized

I have thought about this...

But have you seen the size and weight of an EV battery in real life? Sadly I have...

Hardly gonna be "splash and dash" is it?

I really like that saying "splash and dash"...

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I even been giving some thoughts to swaping out hydrogen 300bar bottles in cars - but this is not gonna be like pumping in LPG at low pressure.

Difficult problems to resolve...