Electric Vehicles?

[cpp]

I don’t even own a car and use public transportation.

That's great, for you !. Surprised you don't bike ride around town

 

[highfigh]

Today the NTSB has raised some concerns on the issue with EV's in a crash with non-EVs. Of note : a Ford’s F-150 Lightning EV pickup is 2,000 to 3,000 pounds (900 to 1,350 kilograms) heavier than the same model’s combustion version. The Mustang Mach E electric SUV and the Volvo XC40 EV, and are roughly 33% heavier than their gasoline counterparts. An electric GMC Hummer weighs about 9,000 pounds (4,000 kilograms), with a battery pack that alone is 2,900 pounds (1,300 kilograms) — roughly the entire weight of a typical Honda Civic. Just found it interesting, the weights of the these EV vehicles.

It's all about getting rid of fossil fuels, not safety. So many details have been omitted in the "We're from the government and we're here, to help" crowd that it could be a long time until the day we can see everything that went wrong.

 

[highfigh]

I don’t even own a car and use public transportation.

That's nice, but public transportation doesn't work for everyone, especially those who don't live in a city.

 

[j_garcia]

I'd use it here, except it sucks.

Same here, if it was good, I would use it.

 

[Trell]

That's great, for you !. Surprised you don't bike ride around town

Nah, it’s public transportation or just walking.

 

[GO-NAD!]

It's all about getting rid of fossil fuels, not safety.

So, as long as the vehicle is emissions-free, nothing else matters?

So many details have been omitted in the "We're from the government and we're here, to help" crowd that it could be a long time until the day we can see everything that went wrong.

I have no idea what this refers to.

 

[Swerd]

On the subject of EV weight …

It's clearly true that EVs are heavy. If you can do a direct comparison with cars that are sold with either internal combustion or electric engines, it's obvious. Most of the extra weight in EVs is from the batteries.

When I was shopping, I narrowed down my choice to the Volvo C40 that I bought, and the Tesla Model Y. Both come with 75 kWh batteries and AWD with two electric motors. Yet, the Tesla's range is said to be 325 miles, and the Volvo C40 or XC40 is 225 miles. Why? It seems the difference is due to total weight. The Tesla Model Y's frame is made of aluminum, with a fair amount of plastic, while the Volvo has a heavier steel frame, responsible for it's relative crush-resistance. I don't know for certain if that is the only reason for the range difference, but I think it explains a lot.

Interestingly, a Tesla sedan (unknown model … perhaps a Model 3) recently was in the news because it went over a steep cliff a bit south of San Francisco. It fell about 250 feet, crashing onto some rocks below. Rescuers were surprised to find that all 4 occupants – 2 adults & 2 children – survived. Most similar crashes result in death for all inside. What about that Tesla might have contributed to that? Certainly, the bottom heavy placement of the heavy batteries had something to do with that. The car landed on it's wheels. We'll find out soon enough, if there is greater inherent strength to that Tesla EV's frame.

 

[Swerd]

On the subject of EVs in cold weather …

I recently saw an article in the Washington Post, titled "Why you might want a heat pump in your electric car".
https://www.washingtonpost.com/climate-solutions/2023/01/07/electric-vehicles-cold-winter-range/

I'll summarize & excerpt:

As frigid temperatures sweep across the country once again – and motorists from Buffalo to Seattle have contended with snow and ice – electric cars (EVs) are facing fresh scrutiny. Lithium-ion batteries perform more sluggishly in cold temperatures, cutting into an EV’s range when temperatures drop close to freezing. For what it’s worth, gas-powered cars also don’t perform perfectly in the cold. But there’s a fix for EVs with dwindling range in winter: the humble heat pump.

Two factors account for why EVs have a slightly harder time in cold weather than gas-powered cars. One stems from the simple reality that the massive lithium-ion batteries in electric cars perform best around 70° F. “Cars are like humans,” said Anna Stefanopoulou, a professor of mechanical engineering at the University of Michigan. “They like room temperature.”

At cold temperatures, lithium ions – which flow from the anode of the battery to the cathode of the battery to create an electrical current – move more slowly through the battery and face greater resistance. That causes the battery to function less efficiently.

But the second reason has to do with the human sitting inside. No one wants to sit in a frigid car during the winter. When it’s cold, gas-powered cars can redirect waste heat from the engine into the cabin to warm the driver and passengers. Gas-powered cars aren’t particularly efficient – when the engine is on, only about 20% of the energy produced is actually going to turn the wheels.

EVs, however, are much more efficient than gas-powered cars. According to the Department of Energy, EVs use over 75% of their energy to propel the car. That means that there isn’t much waste heat available. Instead, many EVs warm their passengers through electric resistance heating – essentially heating a wire and blowing air over it.

Cabin heating accounts for the lion’s share of what drains the EV battery in cold temperatures. According to a 2019 study from AAA that tested five different EVs in 20° F temperatures, on average the cars lost about 41% of their range with the cabin heater on. With the cabin heater off, however, they lost only about 12% of their range.

But not all EVs are created equal. According to a study from Recurrent that looked at real-world data from thousands of electric vehicles, EVs can lose anywhere from only 3% (the Jaguar I-PACE) to 32% (the Chevy Bolt) of their range in subzero temperatures, depending on how the car manages cold weather.

“A car with a heat pump does much better when it drops down to freezing than one without,” Case said.

There are other means to minimize range loss when it’s cold. Many EVs come with seat heaters or even heated steering wheels, which can warm passengers without heating the car’s entire interior. Some cars use the minimal waste heat from the engine to warm the battery and make the charge last longer. EV drivers can also direct their cars to warm up the battery while the car is still plugged in, again extending the range of the vehicle while driving.

Ultimately, experts say, cold weather is not a reason to avoid electric vehicles entirely. Jay Friedland, a policy adviser at the advocacy group Plug in America, points out that the country with the highest number of EVs per capita is Norway, where temperatures frequently hover in the 20 to 30° F (-7 to -1° C) range.

“If you’re going to be driving in cold weather, you just need to know you’re going to have some range loss, and plan accordingly,” Friedland said.

 

[Swerd]

The bottom line:

• The loss in driving range of EVs in cold weather isn't as bad as I had originally feared.
• If you're concerned about an EV's loss of driving range in cold weather, get an EV with a heat pump.

 

[highfigh]

So, as long as the vehicle is emissions-free, nothing else matters?


I have no idea what this refers to.

If a vehicle is 3000 pounds heavier than the average, they will do a lot more damage in a crash and the drivers need to be reminded that the additional weight will cause it to handle differently under many circumstances, like wet roads, excessive speed in cornering, etc.

Congress has mandated many times when they didn't understand the problem, or the solutions. Ethanol is a great example- it's a losing proposition form all angles, yet they refuse to listen when people who know, tell them why it shouldn't be implemented in the way it has been. It's fine for cars and other engines that have been designed to use it, but many weren't and it causes terrible damage to the engines and fuel systems. Alcohol can't be made to avoid absorbing water from the atmosphere, yet they (Congress) don't allow alternatives. The energy density difference isn't huge, but the corrosive properties and phase separation when it absorbs water can't be stopped easily. Phase separation occurs in fuel systems that aren't sealed to the environment and when the ambient temperature fluctuates, the fuel tank 'breathes' via expansion & contraction of the air, pulling in moist air and causing it to condense & mix with the Ethanol.

Don't get me wrong- I don't have a problem with EVs, but I have a problem when Congress tries to mandate their use, end IC engines and believe that everyone will be able to buy one. Then, there's the problem of "How can the grid be improved, so a large number of EVs can be charged at one time?". That last part can't be ignored, nor should they expect people to schedule the recharge time.

 

[highfigh]

On the subject of EV weight …

It's clearly true that EVs are heavy. If you can do a direct comparison with cars that are sold with either internal combustion or electric engines, it's obvious. Most of the extra weight in EVs is from the batteries.

When I was shopping, I narrowed down my choice to the Volvo C40 that I bought, and the Tesla Model Y. Both come with 75 kWh batteries and AWD with two electric motors. Yet, the Tesla has it's range rated at 325 miles, and the Volvo C40/XC40 is 225 miles. Why? It seems the difference is due to total weight. The Tesla Y frame is made of aluminum, with a fair amount of plastic, and the Volvo has a heavier steel frame, responsible for it's relatively crush-resistance. I don't know for certain if that is the only reason for the range difference, but I think it explains a lot.

Interestingly, a Tesla sedan (unknown model) recently was in the news because it went over a steep cliff a bit south of San Francisco. It fell about 250 feet, crashing onto some rocks below. Rescuers were surprised to find that all 4 occupants – 2 adults & 2 children – survived. Most similar crashes result in death for all inside. What about that Tesla might have contributed to that? Certainly, the bottom heavy placement of the heavy batteries had something to do with that. The car landed on it's wheels. We'll find out soon enough, if there is greater inherent strength to the EV's frame.

It may have involved the weight distribution keeping it from tumbling or, depending on how far it fell without hitting the face of the cliff, it ma have righted itself. Not sure I would want to land from that distance in a seated position, though- it would be very hard on the spine.

Softer metals and other materials that are designed to crumple will cause less damage to the contents of a container when it falls- some high school Physics classes involve designing a package that holds an egg, which is dropped from the roof of the school- some break, some don't. I's surprised the battery didn't burn.

 

[Swerd]

I's surprised the battery didn't burn.

We've all seen too many Hollywood movies where a car goes over a cliff and explodes as soon as it hits bottom. I can remember movies where the car exploded while still airborne. The director must have been impatient, or the rigged explosives went off too soon.

Lithium batteries don't burn unless they overheat. Once that happens, those fires are not easily extinguished. They can be smothered under a blanket of CO2, but once that scatters, the hot lithium reignites.

 

[GO-NAD!]

If a vehicle is 3000 pounds heavier than the average, they will do a lot more damage in a crash and the drivers need to be reminded that the additional weight will cause it to handle differently under many circumstances, like wet roads, excessive speed in cornering, etc.

I expect that such reminders will fall on deaf ears. Meanwhile, such vehicles will be far more lethal to other people the vehicle in a crash. The public needs to get it into their collective heads that the age of behemoth PMVs for picking up the groceries needs to die.

Congress has mandated many times when they didn't understand the problem, or the solutions. Ethanol is a great example- it's a losing proposition form all angles, yet they refuse to listen when people who know, tell them why it shouldn't be implemented in the way it has been. It's fine for cars and other engines that have been designed to use it, but many weren't and it causes terrible damage to the engines and fuel systems. Alcohol can't be made to avoid absorbing water from the atmosphere, yet they (Congress) don't allow alternatives. The energy density difference isn't huge, but the corrosive properties and phase separation when it absorbs water can't be stopped easily. Phase separation occurs in fuel systems that aren't sealed to the environment and when the ambient temperature fluctuates, the fuel tank 'breathes' via expansion & contraction of the air, pulling in moist air and causing it to condense & mix with the Ethanol.

Don't get me wrong- I don't have a problem with EVs, but I have a problem when Congress tries to mandate their use, end IC engines and believe that everyone will be able to buy one. Then, there's the problem of "How can the grid be improved, so a large number of EVs can be charged at one time?". That last part can't be ignored, nor should they expect people to schedule the recharge time.

I'm sure Congress understood quite well that ethanol mandates were/are stupid. They were just a sop to the agricultural lobby.

In Canada, forthcoming legislation will mandate emission-free vehicles, so they don't have to be EV's, although that's probably what it means in practical terms. I think the part of the EV equation that isn't stated more loudly, is that we cannot simply replace fossil-fuel burners with EV's, one-for-one. For an emissions-free grid to be possible, it will require far higher public transit usage, with a commensurate investment to make that attainable.

 

[highfigh]

We've all seen too many Hollywood movies where a car goes over a cliff and explodes as soon as it hits bottom. I can remember movies where the car exploded while still airborne. The director must have been impatient, or the rigged explosives went off too soon.

Lithium batteries don't burn unless they overheat. Once that happens, those fires are not easily extinguished. They can be smothered under a blanket of CO2, but once that scatters, the hot lithium reignites.

WRT going over a cliff, FF to 3:20-

Yeah, Hollyweird, where people are shot with small guns and the force knocks them backward, into a wall. The airborne car explosions are rampant. How do you like the sound of metal on metal when someone pulls a knife?

If you want to make a battery burn, pierce the shell- a crash like that can cause this and apparently, it can happen more than a few days after a crash.

 

[Teetertotter?]

Anyone willing to explain?

EV Positives?

EV Negatives?

 

[NINaudio]

not to mention the increased damage done to the roads they operate over. So with EV's not generating any revenue in the form of 'per gallon gas tax' states had better come up with a definitive resolution !

They charge a higher annual registration fee for EV's in Illinois to in part make up for the gas tax revenue that they are missing out on.

 

[William Lemmerhirt]

I think Tesla should be embarrassed for selling “premium” cars that have the fit and finish of junk.

 

[GO-NAD!]

We've all seen too many Hollywood movies where a car goes over a cliff and explodes as soon as it hits bottom. I can remember movies where the car exploded while still airborne. The director must have been impatient, or the rigged explosives went off too soon.

Lithium batteries don't burn unless they overheat. Once that happens, those fires are not easily extinguished. They can be smothered under a blanket of CO2, but once that scatters, the hot lithium reignites.

I don't know how well these car batteries are protected, but after a major impact - such as from falling off a cliff - I can envision sufficient damage to create a short in the battery. With the such a high capacity, I would expect the resulting massive current output to cause it to catch fire.

The EV fires in Florida after Hurricane Ian were caused by salt water-created shorts.

 

[highfigh]

I think Tesla should be embarrassed for selling “premium” cars that have the fit and finish of junk.

High cost doesn't guarantee high quality. Go into multi-million homes and you'll see plenty of flaws in the construction. When I worked for an AV contractor in 2005, we worked on one place that needed the AV working, so they could show it that evening- it sold for $1.4 Million, in 2005 dollars, which is similar to almost $2.2 M, now. It was crap.

 

[cpp]

That's nice, but public transportation doesn't work for everyone, especially those who don't live in a city.

or don't even have public transportation.