Any GTAM'ers own an electric vehicle? | Page 315 | GTAMotorcycle.com

Any GTAM'ers own an electric vehicle?

Brian P

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Tesla go brrrrrrr.


I'm starting to think that the whole heat-pump idea for EV HVAC is overrated. I've seen from tests in Norway that the Ioniq 5 seems to have issues with it, too.

None of these heat pumps do what we normally think of, from what home HVAC heat pumps do ... i.e. suck heat out of the outside air and pump it up to the interior. What they're actually doing is sucking heat out of the battery pack (which produces low-grade heat during operation) and pump it to the interior. Problem is, if driving conditions aren't conducive towards keeping the battery pack in its happiest temperature range but interior HVAC demands more heat than that ... either the battery pack doesn't warm up enough (resulting in slow charging if you stop the car to recharge - this is the problem identified in Norway) or you don't get enough interior heat (Tesla) or the system has to intentionally waste power somewhere in order to produce more heat (which is no more efficient than resistance heating). There's probably a window of outside temperature and driving conditions in which it works OK, but outside those windows, it doesn't accomplish much or has other side effects.

Having watched teardown videos on a few different EVs, I kinda see why GM took the KISS principle with the Bolt. Three separate cooling systems for three separate systems that each have different demands. There's one loop for the motor and inverter and radiator, which don't really care too much about their operating temperature as long as they don't overheat (and these could take forever to warm up, especially if you are driving slowly in cold weather). There's another loop for the battery, which is capable of heating or cooling via the A/C compressor, although most of the time it just lets battery temperature free-float wherever it wants to be and just keeps it within bounds ... and the only time the battery pack would normally require active cooling are under high-ambient conditions when the A/C is running anyhow, and the only time the battery normally needs active heating is during cold-weather charging when the car is plugged in anyhow. The last loop is for the HVAC and uses plain ordinary resistance heating ... which can heat up immediately when it's cold (and there is insufficient heat from the motor/inverter loop or battery loop to keep up). It would be nice in the ideal world to reuse the powertrain heat to help heat the interior ... but under the conditions when you really want interior heat (cold start) it isn't there, and under the conditions when you have excess powertrain heat (high ambient, highway driving) you don't need it. I totally understand the designers saying the heck with it, just use three separate simple systems that each have a simple easy-to-implement control strategy.
 

GreyGhost

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I'm starting to think that the whole heat-pump idea for EV HVAC is overrated. I've seen from tests in Norway that the Ioniq 5 seems to have issues with it, too.

None of these heat pumps do what we normally think of, from what home HVAC heat pumps do ... i.e. suck heat out of the outside air and pump it up to the interior. What they're actually doing is sucking heat out of the battery pack (which produces low-grade heat during operation) and pump it to the interior. Problem is, if driving conditions aren't conducive towards keeping the battery pack in its happiest temperature range but interior HVAC demands more heat than that ... either the battery pack doesn't warm up enough (resulting in slow charging if you stop the car to recharge - this is the problem identified in Norway) or you don't get enough interior heat (Tesla) or the system has to intentionally waste power somewhere in order to produce more heat (which is no more efficient than resistance heating). There's probably a window of outside temperature and driving conditions in which it works OK, but outside those windows, it doesn't accomplish much or has other side effects.

Having watched teardown videos on a few different EVs, I kinda see why GM took the KISS principle with the Bolt. Three separate cooling systems for three separate systems that each have different demands. There's one loop for the motor and inverter and radiator, which don't really care too much about their operating temperature as long as they don't overheat (and these could take forever to warm up, especially if you are driving slowly in cold weather). There's another loop for the battery, which is capable of heating or cooling via the A/C compressor, although most of the time it just lets battery temperature free-float wherever it wants to be and just keeps it within bounds ... and the only time the battery pack would normally require active cooling are under high-ambient conditions when the A/C is running anyhow, and the only time the battery normally needs active heating is during cold-weather charging when the car is plugged in anyhow. The last loop is for the HVAC and uses plain ordinary resistance heating ... which can heat up immediately when it's cold (and there is insufficient heat from the motor/inverter loop or battery loop to keep up). It would be nice in the ideal world to reuse the powertrain heat to help heat the interior ... but under the conditions when you really want interior heat (cold start) it isn't there, and under the conditions when you have excess powertrain heat (high ambient, highway driving) you don't need it. I totally understand the designers saying the heck with it, just use three separate simple systems that each have a simple easy-to-implement control strategy.
So you're saying if it's cold out and you drive a tesla, just keep speeding up until you have sufficient cabin heat?


Good description. Air source heat pump seems like a great fit for ev. I'm surprised that isnt commonly implemented.
 

mimico_polak

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All I know is the heat in the Volt blows chunks. Horrid system.

Need to crank up the temp to 24-25C to actually feel anything. Below that...totally useless. Thought it was only my car, but my neighbour and buddy have the same issues with their Gen2 Volts.
 

Brian P

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TFLtruck has an interview with the chief engineer of the Silverado EV which goes over many of its features.


Price tag for the work-truck version is aligned with Ford Lightning, but for that top-end RST model ... wow. I'd still take the Silverado over the Hummer purely on account of narrower width ... and cleaner styling.
 

Brian P

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Good description. Air source heat pump seems like a great fit for ev. I'm surprised that isnt commonly implemented.

I'm thinking heat pump (almost) isn't worth the bother at all ... just use resistance heating and manage it smartly.

The trouble with air-source heat pump in a mobile application is that the available airflow and heat transfer are limited. If it's -20 C outside, you just can't practically suck enough heat out of enough air to make it work. In a house, you can have a big heat exchanger and blow lots of air across it (and it still doesn't work great when it's -20 C). In a vehicle, you don't want to be drawing lots of air through a heat exchanger, because it kills aero. All EVs that were designed as EVs, have minimal grille openings. (For the pickup trucks, I am happy to see an end to the grille-size war.)

It's way more demanding to heat air, than it is to directly heat the things that you're trying to heat with the air. Window-defrost/defog is killer on energy demand, because you have to run A/C to get the moisture out of the air and then add heat to get the air back up to temperature, and with high airflow to get it across the windows. It's more efficient to electrically heat the windows directly. (Electrically heated windscreens have been done! GM has done it ...) If you do that, there's no waiting for air circulation to slowly start defrost/defog. Heated seats + heated steering wheel (and possibly other heated touch points) use less energy than heating all of the air going through the car. Obviously that can only be taken up to a point, but if you can keep the occupants comfortable by keeping their touch points warm and reduce the air temperature, or use less air volume, it's going to be more efficient.
 

Brian P

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Tesla FSD in the snow.

LOLOLOLOLOL

 

Brian P

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Apparently the reservations for the Silverado RST First Edition sold out in 12 minutes. This is evidently how you sell the public on EVs. GM clandestinely showed off the next Equinox during the Silverado intro, and that looks good, too.
 

cruiserider

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Apparently the reservations for the Silverado RST First Edition sold out in 12 minutes. This is evidently how you sell the public on EVs. GM clandestinely showed off the next Equinox during the Silverado intro, and that looks good, too.

They never mentioned how many were available for reservations. They bragged about delivery of electric Hummer that started in December. Only one was delivered.


Sent from my iPhone using GTAMotorcycle.com mobile app
 

Brian P

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They never mentioned how many were available for reservations. They bragged about delivery of electric Hummer that started in December. Only one was delivered.

Yeah, the frustrating thing is that this is still more than a year away from start of production, and it's going to be a slow ramp-up. Rivian has a head start, but they're still on slow ramp-up. The F150 Lightning will beat this to start of production, but that's also going to be a slow start ... and it will barely get going before it's scheduled for the next major model change.
 

killvino

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$100 fully refundable deposit is all it took.

Being over a year away from production LOL.... I wouldn't be too excited if I was GM.
Need to know how many reservations they had.
Cybertruck was the same. But only didn't sell out because they had no limit (1,256,487 pre-orders so far)

I've gone to the dark side, put an order in for a Model 3 will be trading in or selling the truck.
delivery says March, if it's warm enough by then, I'll try doing my Sudbury visits in it. Worst case, take the wife's car.
Other work locations in London and Kitchener won't be an issue.
 

mimico_polak

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Need to know how many reservations they had.
Cybertruck was the same. But only didn't sell out because they had no limit (1,256,487 pre-orders so far)

I've gone to the dark side, put an order in for a Model 3 will be trading in or selling the truck.
delivery says March, if it's warm enough by then, I'll try doing my Sudbury visits in it. Worst case, take the wife's car.
Other work locations in London and Kitchener won't be an issue.
Super jealous! I want a M3 Performance...but $$$$...way too much for my bank account.
 

killvino

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Super jealous! I want a M3 Performance...but $$$$...way too much for my bank account.
the M3P isn't worth it IMO. it gets the same battery and motors as the LR AWD. you do get bigger brakes, suspension, wheels. but you don't really need those and the ride quality is worse.
there's a $2000 acceleration boost you can buy for the LR AWD that bumps up hp close to the performance and cuts half a sec from the 0-60
 

Evoex

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the M3P isn't worth it IMO. it gets the same battery and motors as the LR AWD. you do get bigger brakes, suspension, wheels. but you don't really need those and the ride quality is worse.
there's a $2000 acceleration boost you can buy for the LR AWD that bumps up hp close to the performance and cuts half a sec from the 0-60
its not worth it unless you plan to track it.

LR is the better buy!

i'll probably get a performance car this year and scale back on the bike.
 

LBV

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i'll probably get a performance car this year and scale back on the bike.
Not to derail too much, but what are you looking for in your performance car?

ie. engine, tranny, sound, handling, size, all-season or only fair weather, etc?

Got any early faves?
 

Evoex

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Not to derail too much, but what are you looking for in your performance car?

ie. engine, tranny, sound, handling, size, all-season or only fair weather, etc?

Got any early faves?
I change my mind every 5 minutes 😂 A performance car, doesn’t have to be 2 door.

Current champ is a C7 Z06 in manual, I’d daily drive it all year round. Runner up is current gen AMG CLS 53s

Tycan or Model S are in the running but since I can’t charge at home I’m not loving that decision. Model S is on my wife’s short list and we’re gonna replace her vehicle first anyways, so maybe she’ll take one for the team. 🙂
 

GreyGhost

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I change my mind every 5 minutes 😂

Current champ is a C7 Z06 in manual, I’d daily drive it all year round.

Tycan or Model S are in the running but since I can’t charge at home I’m not loving that decision. Model S is on my wife’s short list and we’re gonna replace her vehicle first anyways, so maybe she’ll take one for the team. 🙂
You should have bought @Gary 's car. It was a beauty.
 

Evoex

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LBV

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I change my mind every 5 minutes 😂 A performance car, doesn’t have to be 2 door.

Current champ is a C7 Z06 in manual, I’d daily drive it all year round. Runner up is current gen AMG CLS 53s

Tycan or Model S are in the running but since I can’t charge at home I’m not loving that decision. Model S is on my wife’s short list and we’re gonna replace her vehicle first anyways, so maybe she’ll take one for the team. 🙂
I daily drove a 2009 Pontiac G8 GXP with an LS3 V8 and a stick shift for 2 or 3 years. A rare car (the GXP model) that never actually was sold in Canada - I ended up flying down to Nebraska and drove it back. That was when the CAD was on par with the USD. There was maybe 2-3 in all of Canada. Think of it as a 4-door Camaro.

As much as I loved that car, the frequent fuel stops got old after awhile.

If you've got the means to swing it, I'd recommend a car like that as a toy that comes out on nice days and have a fuel efficient daily for the grind. The days you end up driving the toy are special, just like the days you get on the bike.

So the Mustang isn't on your radar?
 

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