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Tesla uses 1/6 the energy compared to gasoline

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I'm getting some pushback on Tesla, people saying "well.... where is that energy coming from when you plug it in to charge it that energy has to come from somewhere", you know the usual you've probably heard it a million times. Its not good enough to say to the FUDsters that it only uses 1/3 of the energy that gasoline uses. So I set out to do the calculations and have them handy when it comes up in a conversation. (1/3 was the figure given by by Tesla back 2006).

Given:
115000 BTU per gallon of gasoline = 33.7 Kwh per gallon
Model Y long range gets 27 Kwh per 100 miles
Model Y long range has a 75 Kwh battery
Equivalent Gasoline car. Lexus RX350 and others get about 20 mpg

Calculation for 300 mile range:
gasoline Kwh over 300 miles
Kwh = 300 mi /20 mi per gal = 15 gal
15 gal at 33.7 Kwh = 505 Kwh

Model Y 27 Kwh per 100 miles
300 mile / 100 = 3
3 * 27Kwh per 100 miles = 81 Kwh

505 kWh for gasoline to 81 Khw for Tesla is about six times more energy.

I know there are a lot of other factors too, energy to get the gasoline, pump oil out of the ground, ship the oil, convert oil to gasoline. transport the gasoline. on and on.
 
This is kind of old, but I found it back when I was puzzling over the same questions before making the jump myself. It convinced me.

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Who cares what other people think. Just drive what you want to drive. It's a heck of a lot cheaper to drive (electricity cost vs gas cost). I seriously wonder who has these conversations though. I've never had anyone say anything other than "how much range does it get" or "cool" when people ask me about mine.

When I decided to buy my MY, I didn't much care about "saving money." If I wanted to save money, I would have bought nothing and just kept driving my old ICE car.
 
Who cares what other people think. Just drive what you want to drive. It's a heck of a lot cheaper to drive (electricity cost vs gas cost). I seriously wonder who has these conversations though. I've never had anyone say anything other than "how much range does it get" or "cool" when people ask me about mine.
Totally agree!
I didn't buy my Tesla to prove anything to others or I really don't care what others think about anything. I bought my MYP because it is fast and that's all I care. =)
 
Is that complete ban of ICE cars or sales of ICE cars?
Sales, luckily. It's CARB aka CA clean air resources bureau, those wankers can be brutal. There's a thread on it around here somewhere. It will phase in ICE reduction in sales by 60% in ten years etc to total ban on ICE sales in 2035. And the kicker is CA will be followed by over a dozen states. The national deadline is like 2045 for ICE sales ban iirc.
 
I seriously wonder who has these conversations though. I've never had anyone say anything other than "how much range does it get" or "cool" when people ask me about mine.

Either people who spend a lot of time online having "discussions", trying to convince others about the car they (the others) need to buy for some reason, or the same thing, in person ( people trying to convince others about why they chose their car, or why the other person should choose an EV).

I dont get it, myself, cause I dont give a flying (you know what) what someone else is driving, nor do I really care if they dont approve of my car for some reason, as long as they are not trying to damage it or something.

There is no conversation I would ever be involved in, in which I would be "pulling out da maths" to try to convince someone of something. I would be saying "You do you, boo".
 
Given:
115000 BTU per gallon of gasoline = 33.7 Kwh per gallon
Model Y long range gets 27 Kwh per 100 miles
Model Y long range has a 75 Kwh battery
Equivalent Gasoline car. Lexus RX350 and others get about 20 mpg

Calculation for 300 mile range:
gasoline Kwh over 300 miles
Kwh = 300 mi /20 mi per gal = 15 gal
15 gal at 33.7 Kwh = 505 Kwh

Model Y 27 Kwh per 100 miles
300 mile / 100 = 3
3 * 27Kwh per 100 miles = 81 Kwh

505 kWh for gasoline to 81 Khw for Tesla is about six times more energy.
It's not nearly that simple. Here's the issue: say I make an offer: I will either give you 33.7 kWh worth of fuel (one gallon of gasoline) or 33.7 kWh worth of electricity. Which one should you choose? Do you really think they're equivalent? Because they're not.

It's true that if your goal was to produce heat, you can get the same amount of heat by running the 33.7 kWh worth of electricity through a PTC heater. You can also get 33.7 kWh worth of heat by burning the gallon of gas.

But wait! We've talked about heat pumps, and how they can be more efficient than using electricity to generate heat directly. Put the electricity into a heat pump that scavenges heat from somewhere else, and you can produce more than 33.7 kWh worth of heat with your 33.7 kWh worth of electricity.

Or is it mechanical work you're after? Burning the gallon of gas produces 33.7 kWh worth of heat, but you can't do 33.7 kWh worth of work with it. There are limitations on the thermal efficiency of any heat engine, and the limit is related to the absolute temperature of the hot reservoir and the cold reservoir. Why's this important? Because making electricity requires turning the heat into mechanical work, which then turns a generator to produce electricity. In other words, 1 kWh worth of electricity is more useful than 1 kWh worth of heat, simply because it takes more than 1 kWh worth of heat to generate 1 kWh worth of electricity. This is true even if you look at the theoretical best case scenario (which isn't achievable in the real world).

Of course, in the real world, it's generally always better to do the conversion of heat to mechanical work to electricity at an industrial scale, then transmit it to a battery, than trying to do it in a vehicle directly. Car engines have to be small and light because they carry their own weight around. Power to weight ratio matters, so they make compromises and vent exhaust to the cold reservoir while it's still quite hot. This decreases efficiency compared to industrial scale generators, which can be bulky and have multiple turbines to extract more energy from the expanding gases. But comparing the heat energy in 1 gallon of gas to 33.7 kWh worth of electricity isn't the right way to do the comparison (which by the way is what the EPA does when they give you a MPGe rating).
 
I seriously wonder who has these conversations though. I've never had anyone say anything other than "how much range does it get" or "cool" when people ask me about mine.

Either people who spend a lot of time online having "discussions", trying to convince others about the car they (the others) need to buy for some reason, or the same thing, in person ( people trying to convince others about why they chose their car, or why the other person should choose an EV).
I actually had this conversation with a buddy on a golf course, though I agree that it's rare. He's on the conservative end and gets his information from you know where. But he's still fairly open-minded, and genuinely wants to know. He quoted the same myths about battery pollution and electricity being from fossil-burning power plants, which lead to the expected conclusion that EV is just as bad or even worse than ICE. I used the standard arguments to debunk those, but unfortunately I didn't have concrete numbers at the time so he wasn't convinced.

Most of the time it's not the one-to-one conversations that will help society-wide adoption, but rather "influencers" - news anchors, opinion hosts, podcasts, social media, etc. The more articles in the spirit of the OP get into mainstream popular culture, the harder it is for FUD and conspiracy and myths to flourish. And just perhaps if you have a real conversation with someone else, you can quote facts to be more convincing than I was.

Comparing a Model 3 to a Toyota Corolla in total carbon footprint - Model 3 will be more environmental after 13K miles
 
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This whole conversion to electricity to gas to KwH is mostly confusing. I tell people that electrics are a fourth as expensive to drive. That's where it counts, at the wallet. Just comparing power usage doesn't factor in the oil and filter changes we DON'T have, nor the trips to the gas station. I ask how many people have a gas station in their garage. Answer? None. "Them thangs are dangerous!" But we CAN just use a simple outlet, any kind, and fill our cars. I used to live out in the country, and it was an eight-mile drive to the gas station, but my garage outlet was sitting just at the back corner of my car. There's no comparison.

Whenever someone pulls out the line about pollution up the stream, I can point to gas production, which has MORE pollution upstream. They can't win.
 
It's not nearly that simple. Here's the issue: say I make an offer: I will either give you 33.7 kWh worth of fuel (one gallon of gasoline) or 33.7 kWh worth of electricity. Which one should you choose? Do you really think they're equivalent? Because they're not.

It's true that if your goal was to produce heat, you can get the same amount of heat by running the 33.7 kWh worth of electricity through a PTC heater. You can also get 33.7 kWh worth of heat by burning the gallon of gas.

But wait! We've talked about heat pumps, and how they can be more efficient than using electricity to generate heat directly. Put the electricity into a heat pump that scavenges heat from somewhere else, and you can produce more than 33.7 kWh worth of heat with your 33.7 kWh worth of electricity.

Or is it mechanical work you're after? Burning the gallon of gas produces 33.7 kWh worth of heat, but you can't do 33.7 kWh worth of work with it. There are limitations on the thermal efficiency of any heat engine, and the limit is related to the absolute temperature of the hot reservoir and the cold reservoir. Why's this important? Because making electricity requires turning the heat into mechanical work, which then turns a generator to produce electricity. In other words, 1 kWh worth of electricity is more useful than 1 kWh worth of heat, simply because it takes more than 1 kWh worth of heat to generate 1 kWh worth of electricity. This is true even if you look at the theoretical best case scenario (which isn't achievable in the real world).

Of course, in the real world, it's generally always better to do the conversion of heat to mechanical work to electricity at an industrial scale, then transmit it to a battery, than trying to do it in a vehicle directly. Car engines have to be small and light because they carry their own weight around. Power to weight ratio matters, so they make compromises and vent exhaust to the cold reservoir while it's still quite hot. This decreases efficiency compared to industrial scale generators, which can be bulky and have multiple turbines to extract more energy from the expanding gases. But comparing the heat energy in 1 gallon of gas to 33.7 kWh worth of electricity isn't the right way to do the comparison (which by the way is what the EPA does when they give you a MPGe rating).
"It's not nearly that simple" I suspected that, and am glad someone came forth with the explanation of why its not that simple. "it takes more than 1 kWh worth of heat to generate 1 kWh worth of electricity" does not support the one third the energy claim by Tesla in the beginning. I've not seen that claim lately. The other reason to transition to EV that no one talks about is that it's safer to get the energy conversion done in a large scale power generating plant than a refinery. Think about the 1989 Phillips explosion in Pasadena, the BP Texas City explosion and countless other explosions. Hydrocarbon processing is dangerous.
 
This whole conversion to electricity to gas to KwH is mostly confusing. I tell people that electrics are a fourth as expensive to drive. That's where it counts, at the wallet. Just comparing power usage doesn't factor in the oil and filter changes we DON'T have, nor the trips to the gas station. I ask how many people have a gas station in their garage. Answer? None. "Them thangs are dangerous!" But we CAN just use a simple outlet, any kind, and fill our cars. I used to live out in the country, and it was an eight-mile drive to the gas station, but my garage outlet was sitting just at the back corner of my car. There's no comparison.

Whenever someone pulls out the line about pollution up the stream, I can point to gas production, which has MORE pollution upstream. They can't win.
Yes it is confusing and I've puzzled over it for a while. STS-134, above, expressed it very well.
 
No one has taken into account the source of the electricity either -- some places use more fossil fuels to produce it than others. Does your electricity come from coal, hydro, nuclear, or something else? Generally EV's are more efficient at using power, but that power still comes from somewhere.
 
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No one has taken into account the source of the electricity either -- some places use more fossil fuels to produce it than others. Does your electricity come from coal, hydro, nuclear, or something else? Generally EV's are more efficient at using power, but that power still comes from somewhere.
But even in areas that use "dirty" power, EVs do have one advantage: as the grid is cleaned up, they become cleaner without the owners having to do anything. Burning a gallon of gas on the other hand adds a certain amount of carbon to the atmosphere and there's not anything you can do about it.