Climate and EV's

[Aidan]

Does anyone have information on whether the climate is a concern for an electric vehicle for instance does it make any difference if you live in Alaska or Mexico and drive an EV
Does the climate contribute to any good or bad technicalities the car my face because of extreme weather?

 

[Tcdn]

Both gas and electric vehicles have decreased efficiency in cold weather

 

[Anonymous]

My range experiences in an EV in Canada.
http://mysmartelectricdrive.blogspot.ca/2014/03/range-experiences.html

 

[SeanNelson]

Does the climate contribute to any good or bad technicalities the car my face because of extreme weather?

Electric cars can use extra power in summer to run the air conditioner, and a lot of extra power in winter to run the heater. That means you won't be able to drive as far on a full charge. It can cut the range by as much as 30 to 40% in extreme cases.

 

[GetOffYourGas]

In addition to things mentioned above, heat is a major factor in battery longevity. Now the Bolt has active cooling on its battery pack, so in theory a hot climate should be livable. But it will take more energy to keep things cool in Mexico than in Alaska. And if you don't plug it in, I don't know if the TMS will run off the battery power. Even if it does, eventually it will deplete the battery.

 

[NeilBlanchard]

Cold weather has less effect on an EV's efficiency, than it does for an ICE car. Warm up time is the main challenge for ICE's.

If you have a direct heating defroster (like the e-Golf) and if you have heated seats and heated outside mirrors (like most EV's today), then you won't lose too much range in the winter - the main loss comes from needing to warm the battery in extreme cold weather.

If you are driving in a strong snow storm or ice storm, and you need to run the cabin heater, then this will take more energy; in particular if the heater is a resistance heater. Heat pumps take less energy, though.

In an ICE, you take the heat for granted - because <b>75-85%</b> of the gasoline consumed is WASTED! In an EV, you need to dress warmly, use the seat heaters, and direct defrosters, and use the space heater only when you really need it.

The worst I have seen in 2 winters with two EV's is about a 28% loss of range. With an ICE, the loss is dependent on whether you drive it far enough to warm it up, and then how far you drive it after that.

 

[GetOffYourGas]

Cold weather has less effect on an EV's efficiency, than it does for an ICE car.

Depends on how you look at efficiency. An ICE car throws away most of its energy as heat. In the winter, that heat can be put to useful work (i.e. warming up the cabin). So an ICE car's efficiency goes up dramatically in the cold weather.

 

[WetEV]

In addition to things mentioned above, heat is a major factor in battery longevity. Now the Bolt has active cooling on its battery pack, so in theory a hot climate should be livable. But it will take more energy to keep things cool in Mexico than in Alaska. And if you don't plug it in, I don't know if the TMS will run off the battery power. Even if it does, eventually it will deplete the battery.

Active cooling doesn't mean that the battery pack stays at the same temperature. TMS aka active cooling will reduce the spread between hot places and cool places, but battery life will still be shorter in Phoenix than in Seattle.

 

[GetOffYourGas]

In addition to things mentioned above, heat is a major factor in battery longevity. Now the Bolt has active cooling on its battery pack, so in theory a hot climate should be livable. But it will take more energy to keep things cool in Mexico than in Alaska. And if you don't plug it in, I don't know if the TMS will run off the battery power. Even if it does, eventually it will deplete the battery.

Active cooling doesn't mean that the battery pack stays at the same temperature. TMS aka active cooling will reduce the spread between hot places and cool places, but battery life will still be shorter in Phoenix than in Seattle.

True, but a proper (IMO) TMS will reduce the spread enough so that heat is no longer the driving factor in battery life. Empirically, this seems to be the case with the Volt (although admittedly, nobody outside of GM knows for certain).

 

[WetEV]

Active cooling doesn't mean that the battery pack stays at the same temperature. TMS aka active cooling will reduce the spread between hot places and cool places, but battery life will still be shorter in Phoenix than in Seattle.

True, but a proper (IMO) TMS will reduce the spread enough so that heat is no longer the driving factor in battery life. Empirically, this seems to be the case with the Volt (although admittedly, nobody outside of GM knows for certain).

The Volt might be doing much better, but isn't clear if that is due to TMS and/or different battery chemistry.

 

[Anonymous]

an ICE car's efficiency goes up dramatically in the cold weather.

Not true for any gas car I owned here in Canada. The mpg (or l/100km) of any of the dozen gas cars I owned was always worse in the winter compared to the spring/fall. While waste heat can be re-used to heat the cabin in a gas car, the car itself still uses more energy to drive in cold weather.

 

[GetOffYourGas]

an ICE car's efficiency goes up dramatically in the cold weather.

Not true for any gas car I owned here in Canada. The mpg (or l/100km) of any of the dozen gas cars I owned was always worse in the winter compared to the spring/fall. While waste heat can be re-used to heat the cabin in a gas car, the car itself still uses more energy to drive in cold weather.

You're missing the point. Heat is valid work. The car is doing more work with the gas than just driving. Therefore, MPG (or l/100km) is not a proper measure of efficiency. It is incomplete. If you include heating the cabin, every single gas car you have owned up there in Canada has been more efficient in the winter.

 

[DucRider]

 

[NeilBlanchard]

an ICE car's efficiency goes up dramatically in the cold weather.

Not true for any gas car I owned here in Canada. The mpg (or l/100km) of any of the dozen gas cars I owned was always worse in the winter compared to the spring/fall. While waste heat can be re-used to heat the cabin in a gas car, the car itself still uses more energy to drive in cold weather.

Exactly - ICE cars lose a lot of efficiency in cold weather - longer warm up time, more friction. My ICE would drop about 27-28% from summer to winter. If you drive without needing the cabin heater or air defroster, an EV only drops ~15%. As the temperature drops into the single numbers, it drops a bit more because the battery has stay warm.

All cars have higher aerodynamic drag in cold air, and snow and ice increases rolling resistance and slippage.

 

[GetOffYourGas]

I love this infographic. It has been around for a few years, but it's just as valid today as it was then. The interesting part is that the savings of going EV over ICE actually increases in cold weather, despite its energy usage increasing by a larger percentage.

 

[GetOffYourGas]

Exactly - ICE cars lose a lot of efficiency in cold weather - longer warm up time, more friction. My ICE would drop about 27-28% from summer to winter. If you drive without needing the cabin heater or air defroster, an EV only drops ~15%. As the temperature drops into the single numbers, it drops a bit more because the battery has stay warm.

All cars have higher aerodynamic drag in cold air, and snow and ice increases rolling resistance and slippage.

Just to clarify here, I am not denying this. It is absolutely true that the amount of energy used to propel the car forward increases at lower temperatures.

My only point is that if you look at the whole system, by utilizing the otherwise wasted heat, you are increasing the amount of work done by burning the gasoline. So the driving efficiency decreases, but the vehicle's efficiency increases. If you don't heat your car in the winter, this would not be the case. My assumption here is that most (all?) people use heat extensively during the winter.

So thanks for the clarification. And please resist the urge to put up a strawman argument against me.

 

[Anonymous]

Heat is valid work. The car is doing more work with the gas than just driving. Therefore, MPG (or l/100km) is not a proper measure of efficiency

Pay $ for gas, that gas takes a car fewer km in the winter. Efficiency is directly related to how far a car can go based on the input energy. That's the definition of efficiency. The fact waste heat is reused is preventing the gas car from doing even worse than if it used an electric heater, The math is easy, mgp is a true measure of efficiency, your point is taken, that gas cars are pathetic in the winter, and waste heat helps make them slightly less pathetic.

 

[SeanNelson]

Heat is valid work. The car is doing more work with the gas than just driving. Therefore, MPG (or l/100km) is not a proper measure of efficiency

Efficiency is directly related to how far a car can go based on the input energy. That's the definition of efficiency.

You're both right according to your own definitions.

But IMHO considering ICE heat to be "work" is at odds with the widely accepted description of ICE HVAC systems as making use of "waste heat". It's valid from a certain perspective, but isn't the way most people look at the issue.

 

[GetOffYourGas]

Heat is valid work. The car is doing more work with the gas than just driving. Therefore, MPG (or l/100km) is not a proper measure of efficiency

Efficiency is directly related to how far a car can go based on the input energy. That's the definition of efficiency.

You're both right according to your own definitions.

But IMHO considering ICE heat to be "work" is at odds with the widely accepted description of ICE HVAC systems as making use of "waste heat". It's valid from a certain perspective, but isn't the way most people look at the issue.

Thank you Sean. This is what I've been trying to say.

BTW, efficiency is defined as "the ratio of the useful work performed by a machine or in a process to the total energy expended or heat taken in". So gallons of gasoline is a proxy for the "energy expended". SmartElectric and I simply differ in opinion over whether heating the cabin should be included as "useful work".

SmartElectric's argument is that it should not count, and the only useful work is miles driven. And it's true that that's how most people think of it.

My argument is that this is an incomplete view. My argument is that useful work should include heating the cabin, because most people (especially ICE drivers) keep their cars toasty warm in the winter time.

 

[Aidan]

Really helpful responses thank you am I to assume that the battery itself generates heat and does this transfer to the interior of the vehicle