Electric cars priviledges in UK (London) and Channel Tunnel crossing speeds

[nctnico]

I'm really surprised about how many people don't like the idea of EVs on an electronics engineering forum. EVs take a complex mechanical device with many bits to go wrong (recently a friend has just had to completely rebuild an engine after his timing belt slipped)  and replace it with a simple inverter and motor assembly. It's a completely different way of building a car. It's just the chemical batteries that get in the way at the moment, but this should change over time.

If you think an EV is just batteries and a motor + inverter you are sooo wrong. Just look at the battery and electronics cooling system of a Chevrolet Volt or Tesla Model-S. An ICE based car doesn't need the 'aircondition' to cool the engine so it can run. An EV however cannot work properly without the 'airconditioning' being in tiptop condition https://gigaom.com/2010/09/29/electric-car-101-liquid-vs-air-battery-cooling-systems/ . An EV just trades in one problem for the other.

[richard.cs]

Solar corresponds to peak usage pretty well (industrial use during the day, air-con). Also, 30c/kWh makes EVs unattractive? It's still an order of magnitude cheaper than petrol.

He was talking about the UK, peak demand here is around 18:00-1900 http://www.nationalgrid.com/ngrealtime/realtime/realtime1daylarge.aspx That should (always) show the last 24 hours if I've got the link right, y-axis in megawatts. Peak today was about 5 GW more than relatively flat the daytime demand. We don't use much aircon here even in the summer and the is a lot of electricity used for domestic heating and cooking. From memory we hit around 56 GW in the winter.

[bookaboo]

Agreed.

I'm really surprised about how many people don't like the idea of EVs on an electronics engineering forum.

Pretty simple - EEs without rose tinted glasses understand how shit batteries are.

If you are talking Nissan leaf and hybrid type stuff then yeah it's pretty shit. On the other hand Tesla specifications and their entire approach is ground breaking.

[tom66]

Batteries are expensive - but those used in, for example the Model S, cannot be described by in any way as "shit". They are engineered to make the most of what is available. Li-ion has hit the point of being convenient enough and power dense enough to drive a car. I really don't mind 30 minutes to supercharge my vehicle's battery, given the slight inconvenience is outweighed by charging at home every night.

I'm really surprised about how many people don't like the idea of EVs on an electronics engineering forum. EVs take a complex mechanical device with many bits to go wrong (recently a friend has just had to completely rebuild an engine after his timing belt slipped)  and replace it with a simple inverter and motor assembly. It's a completely different way of building a car. It's just the chemical batteries that get in the way at the moment, but this should change over time.

If you think an EV is just batteries and a motor + inverter you are sooo wrong. Just look at the battery and electronics cooling system of a Chevrolet Volt or Tesla Model-S. An ICE based car doesn't need the 'aircondition' to cool the engine so it can run. An EV however cannot work properly without the 'airconditioning' being in tiptop condition https://gigaom.com/2010/09/29/electric-car-101-liquid-vs-air-battery-cooling-systems/ . An EV just trades in one problem for the other.

Nissan Leaf uses air cooling (fans) for the battery. Liquid cooling is best for longevity but is not necessary for a low performance vehicle such as the Leaf. (Inverter and motor are cooled I think.)

Doesn't virtually every production petrol car use liquid cooling? And have you ever looked at how complex such systems are in a petrol engine, all running off the serpentine belt? If that belt snaps you loose everything. Power steering, cooling, interior heat/cool, air con, etc. Maybe the fan would still work off 12V...

EV = Everything electrically driven. Aircon/PTC heater from HV pack, pumps from 12V system.

A Model S can also drive without the cooling system functional but goes into limp mode, power significantly limited (to about 60kW which is enough to go 70mph, but accel is poor.)

And yes, the cooling system is fairly complex... but it is a car now offering 691hp across front and rear axles... that's supercar territory.

[bookaboo]

I'm really surprised about how many people don't like the idea of EVs on an electronics engineering forum. EVs take a complex mechanical device with many bits to go wrong (recently a friend has just had to completely rebuild an engine after his timing belt slipped)  and replace it with a simple inverter and motor assembly. It's a completely different way of building a car. It's just the chemical batteries that get in the way at the moment, but this should change over time.

If you think an EV is just batteries and a motor + inverter you are sooo wrong. Just look at the battery and electronics cooling system of a Chevrolet Volt or Tesla Model-S. An ICE based car doesn't need the 'aircondition' to cool the engine so it can run. An EV however cannot work properly without the 'airconditioning' being in tiptop condition https://gigaom.com/2010/09/29/electric-car-101-liquid-vs-air-battery-cooling-systems/ . An EV just trades in one problem for the other.

ICE vehicles require a cooling system as well and it's regularly a weak point in the system. I would love to see verified reliability figures on Teslas and how they compare.

With regard to the debate surrounding renewables, no one denies that in an unregulated system burning fossil fuels is a lot more cost effective than renewable energy. However cost comparisons are entirely pointless without taking into consideration the true cost of releasing carbon. It's a seperate question and I don't know the answer to it but the consensus seems to be that this cost is high hence carbon taxes that should (if the math is done right) reflect the true cost of carbon based power.
The libertarians screaming about government interference can go back to the 1800's for their air and water if they want.

[nctnico]

I'm really surprised about how many people don't like the idea of EVs on an electronics engineering forum. EVs take a complex mechanical device with many bits to go wrong (recently a friend has just had to completely rebuild an engine after his timing belt slipped)  and replace it with a simple inverter and motor assembly. It's a completely different way of building a car. It's just the chemical batteries that get in the way at the moment, but this should change over time.

If you think an EV is just batteries and a motor + inverter you are sooo wrong. Just look at the battery and electronics cooling system of a Chevrolet Volt or Tesla Model-S. An ICE based car doesn't need the 'aircondition' to cool the engine so it can run. An EV however cannot work properly without the 'airconditioning' being in tiptop condition https://gigaom.com/2010/09/29/electric-car-101-liquid-vs-air-battery-cooling-systems/ . An EV just trades in one problem for the other.

ICE vehicles require a cooling system as well and it's regularly a weak point in the system.

In an ICE car the cooling system is just a pump and a radiator at low pressure. Usually the coolant pump needs replacing around 200k km to 300k km. Nowadays the coolant can stay in the car as long as the car lasts.

An EV has a cooling system which is basically an airconditioning (AC). If you ever had a car with AC then you know it needs service every few years to have it running at full capacity. Due to the high pressure there is always a little bit of leakage. And you may need to change expensive parts like the compressor (it gets much more use in an EV than in an ICE) and condensor (which is at the front of the car taking all the water and other parts flying into the grill). I recently had the condensor on my car replaced which cost me 400 euro at a universal AC repair shop.

[tom66]

The AC system in Model S is only used when supercharging/using chademo and using warp speed continuously.  When driving along the motorway, it doesn't even use the cooling fans, just dissipates it in the radiators using moving air. It only needs to dissipate a few kW in most cases, doesn't even actively cool the pack until it hits 55C.

You can get an A/C top up near where I live for about £30, it's not a significant maintenance item.

Picture from Model S diagnostic utility, I believe car was cruising when this image was taken... chiller not in use:

[richard.cs]

If you ever had a car with AC then you know it needs service every few years to have it running at full capacity. Due to the high pressure there is always a little bit of leakage.

Car AC has this problem mainly because of leakage from the shaft seals, rotating seals being a consequence of belt driving from an ICE. Electrically driven AC can solve this problem by having the motor in a sealed can with the refrigerant. Universal on domestic refrigerators and common (here at least) for small/medium sized AC units. Even some ICE cars are now going to all-electric accessories with just the (larger) alternator driven from the belt. This simplifies the mechanics and for things like a power steering pump you can significantly reduce wasted power by not having a pump running continuously.

[sunnyhighway]

An ICE based car doesn't need the 'aircondition' to cool the engine so it can run.

Try removing this system from your ICE and let me know what the results are.

[Rufus]

Batteries are expensive - but those used in, for example the Model S, cannot be described by in any way as "shit".

Needing to make 1/3rd of the car battery to get a vaguely acceptable range is shit. Needing 6000 individual cells is shit and ridiculous. Needing to be nursed with a vast amount of monitoring circuitry is shit. Needing to be actively cooled and warmed is shit. Being expensive and having a limited life is shit.

A tin can to hold chemical fuel has none of these problems, dirt cheap, lasts forever and has about 60 times higher energy density.

[nctnico]

An ICE based car doesn't need the 'aircondition' to cool the engine so it can run.

Try removing this system from your ICE and let me know what the results are.

Maybe try to read first before making a fool out of yourself

@tom66: An 'AC top up' is not the way to go because that usually doesn't include replacing the oil and testing how much coolant is still in the system. A top-up is a cheap fix to keep yourself cool in an old car (which you may not want to use much longer) but I wouldn't do that on an EV where the airconditioning/cooling system is a vital part of the car.

[bookaboo]

Needing to make 1/3rd of the car battery to get a vaguely acceptable range is shit.

The Model S has loads of room and has storage space where an ICE would go.

Needing 6000 individual cells is shit and ridiculous.

Ok, why? What is the inherent shitiness of needing X amount of components?
By that measure everything is complete shit as they are actually made of lots of atoms, which themselves are probably shit too as they are made of lots of stuff. Shit indeed.

Needing to be actively cooled and warmed is shit.

As opposed to ICE and virtually everything else under the sun that prefers to be kept in a certain temperature range.

having a limited life is shit.

Teslas own data and reports from users show the battery bank to perform incredibly well over the long term. A Norwegian blogger calculated his battery has 0.5% less capacity after 50,000 Kilometers. Clearly shit.

Being expensive.

I'll give you that one but Tesla have the optimal approach to attaining economies of scale.

[sunnyhighway]

An ICE based car doesn't need the 'aircondition' to cool the engine so it can run.

Try removing this system from your ICE and let me know what the results are.

Maybe try to read first before making a fool out of yourself

An EEV needs the batteries within a certain temperature range for reliable operation.
An ICE needs the engine block within a certain temperature range for reliable operation.

Both use a complex system to accomplish that
The EEV uses air as a transfer medium and the ICE use a liquid as a transfer medium.

[nctnico]

An ICE based car doesn't need the 'aircondition' to cool the engine so it can run.

Try removing this system from your ICE and let me know what the results are.

Maybe try to read first before making a fool out of yourself

An EEV needs the batteries within a certain temperature range for reliable operation.
An ICE needs the engine block within a certain temperature range for reliable operation.

Both use a complex system to accomplish that
The EEV uses air as a transfer medium and the ICE use a liquid as a transfer medium.

More nonsense. Please compare the picture of the cooling/heating system of the Tesla and compare to the picture you posted. An ICE has a simple bi-metal thermostat which regulates the coolant temperature. It is so simple it can't go wrong when a car is reasonably well maintained.

[eneuro]

Both use a complex system to accomplish that
The EEV uses air as a transfer medium and the ICE use a liquid as a transfer medium.

It depends:
High Performance Liquid Cooled AC Motors

Even in custom garage conversions of classic cars to electric vehicles its motor is liquid cooled-air transfer is good to cool PC computers 

[tom66]

More nonsense. Please compare the picture of the cooling/heating system of the Tesla and compare to the picture you posted. An ICE has a simple bi-metal thermostat which regulates the coolant temperature. It is so simple it can't go wrong when a car is reasonably well maintained.

The primary reason Tesla's cooling system is so complicated is because they want to get the most range out of the battery. As one example, they recycle waste heat from the battery and motor into the heating system, like an ICE. Also, when you use the interior heat or AC, some of that heating/cooling can be redirected to the battery if it's not needed to maintain cabin temperature. Also, they reduce drag by having a set of active louvers at the front of the vehicle, these only open when full cooling is required.

It's also an early vehicle. ICE manufacturers have had 100+ years to perfect and reduce the cost of the cooling system. It's still a very complicated system with many parts to fail, especially around a vibrating, hot and rotating engine.  One of the reasons Tesla did not use a simple bimetal thermostat is they have software control over all parts of the cooling system, for example they can change the active/passive cooling targets with newer releases. For example they recently increased the 55°C  active cooling target to 60°C. They probably changed this because in their long term tests they determined that the pack would still have good range over its lifespan if allowed to hit 60°C and it increases the range of the pack during high performance exertions.

All of this takes up a small amount of the space where an engine would be...
http://www.teslamotorsclub.com/attachment.php?attachmentid=17176&d=1361810978

[tom66]

Even in custom garage conversions of classic cars to electric vehicles its motor is liquid cooled-air transfer is good to cool PC computers 

The original Tesla Roadster had an air cooled motor and liquid cooled inverter. It had no problems putting out 200kW for some time.