Cost of driving: electricity vs. gasoline

[mheslep]

I'm going to get a gas generator and use that to charge up my electric car to save gas! LOL Obviously a gallon of gas produces more power than a battery can collect from a gallon of gas.

Most of that 'power' goes out the exhaust pipe as wasted heat.

Any time you charge a battery you lose at least 60% of the electricity to heat and charge dissipation into the air around the terminals...

False. No battery loses that much energy on charge including losses in the charger; lead - acid is very inefficient in discharge but Li Ion batteries used in electric vehicles are not; they incur losses approximately as the poster above suggested.

...Gasoline engines are already extremely efficient at converting tiny gas explosions into physical movement.

No, the designs for internal combustion engines are ingenious, integrating hundred or moving parts, and they have incorporated innumerable innovations in the last century. However they are still far short of the efficiency of an electric motor in converting stored energy to motion and will remain so.

 

[PattiM]

Thanks for the great discussion! I'm a physicist/researcher in combustion and the atmosphere and I'm thinking about switching from my Honda silverwing to this:

http://www.zelectricvehicle.com/17.html

The Carnot cycle rules everything from extracted resources (coal/oil) to power generation/distribution/use, but fiat currency is utterly labile. And, well... gasoline *is* going away forever. Prices will never go down except, maybe, for the wealthy and/or the few. This is clearly known and you can spend and afternoon at the Smithsonian Institute last March to get the gory details here:

http://www.youtube.com/watch?v=ZiG3I5DaPrE&feature=list_other&playnext=1&list=SP2817969CA87E5B47

So the question is not if, but when we will convert to electrics. And even when we do that, life in Western nations will never again be like it has been for the last 40 years. My problem is, even the best sources just don't yet know what it *will* be like - so I'm a little anxious about spending $6K at this time. My Honda cost $6K new in '07, but now is $9.5K new - so waiting can be a bad idea sometimes.

Thoughts?

The Patricia

EDIT: OOPS! (this may be off-topic) I just remembered that it is probably better to bicycle since I only live 4 miles to work. <<blush!>> Has anyone done an energy calculation for this case?

Has anyone thought about cross country trips? I guess you could rent a cheap motel ever few hours and surreptitiously use an extension cord to charge the scooter - or do it at a rest stop. Maybe that's a non-starter until an electric infrastructure is built.

 

[OmCheeto]

Thanks for the great discussion! I'm a physicist/researcher in combustion and the atmosphere and I'm thinking about switching from my Honda silverwing to this:

http://www.zelectricvehicle.com/17.html

The Carnot cycle rules everything from extracted resources (coal/oil) to power generation/distribution/use, but fiat currency is utterly labile. And, well... gasoline *is* going away forever. Prices will never go down except, maybe, for the wealthy and/or the few. This is clearly known and you can spend and afternoon at the Smithsonian Institute last March to get the gory details here:

http://www.youtube.com/watch?v=ZiG3I5DaPrE&feature=list_other&playnext=1&list=SP2817969CA87E5B47

So the question is not if, but when we will convert to electrics.

No one knows.

And even when we do that, life in Western nations will never again be like it has been for the last 40 years. My problem is, even the best sources just don't yet know what it *will* be like

It will be much quieter.

- so I'm a little anxious about spending $6K at this time. My Honda cost $6K new in '07, but now is $9.5K new - so waiting can be a bad idea sometimes.

Thoughts?

Most electric vehicles are primarily designed as urban vehicles, so if you do lots of long distance trips when off work, it may not make sense for you buy one.

The Patricia

EDIT: OOPS! (this may be off-topic) I just remembered that it is probably better to bicycle since I only live 4 miles to work. <<blush!>> Has anyone done an energy calculation for this case?

I usually quote 250 watt hours per mile. But I see your ZEV6100 claims only 41 through 64 watt hours per mile. So if you're paying $0.11 per kwh, it will cost you about a nickel a day to get back and forth to work. So if you don't mind your electric bill going up a $1.00 per month, and never having to go to a gas station again, then the ZEV might be a good idea.

Has anyone thought about cross country trips?

Most EV'ers would recommend renting a gas powered vehicle, if you insist on driving cross country. Personally, I'll take my EV to the airport and fly across country, then rent an EV when I get there.

I guess you could rent a cheap motel ever few hours and surreptitiously use an extension cord to charge the scooter - or do it at a rest stop. Maybe that's a non-starter until an electric infrastructure is built.

There are alternatives, and new alternatives will be thought up every day.

Trailer Maker Creates Novel Way To Unshackle The Electric Car

I guess this wouldn't work on your scooter, so I'd keep your Silverwing. Or you could invent a similar side-car device for your scooter.

Some might say these type devices defeat the purpose of having an EV, but I don't think so. EV's are incredibly inexpensive to operate, and renting a diesel-electric generator for your cross country trip seems quite logical, if you have some phobia of planes, or rental cars. Or even if it's simply that thousand mile long wind in your hair feeling that you're after.

 

[mheslep]

Trailer Maker Creates Novel Way To Unshackle The Electric Car

Interesting idea, but at this price

The trailer, which Cashen expects will cost about $15,000 ...

they will have to rent the thing for the occasional long trip as one can buy a 4-seat gasoline vehicle for less.

 

[OmCheeto]

Interesting idea, but at this price

$15,000

Yah, I saw that. It might be the economies of scale at work. How many 25kw diesel generators are sold every year? Off the shelf tow-able generators of that capacity do cost that much. I guess I'm just used to the little ones I've been looking at that run closer to 6 watts/dollar. Still > $4000 though.

they will have to rent the thing for the occasional long trip as one can buy a 4-seat gasoline vehicle for less.

Yah. I think I realized they would be an expensive item to be parked next to your house 50 weeks out of the year

...and renting a diesel-electric generator for your cross country trip seems quite logical...

 

[PattiM]

I usually quote 250 watt hours per mile. But I see your ZEV6100 claims only 41 through 64 watt hours per mile. So if you're paying $0.11 per kwh, it will cost you about a nickel a day to get back and forth to work. So if you don't mind your electric bill going up a $1.00 per month, and never having to go to a gas station again, then the ZEV might be a good idea.

Wow! I spend about $35 a month to fuel the silver wing. That's a big difference that is only going to get bigger. But it would still take years to reach cost equivalency, even figuring in a smoothly extrapolated increase in the cost of gasoline (likely not valid). Rationing is a real possibility for the coming decade(s). I guess I could compensate a little by selling my silver wing.

 

[bahamagreen]

Whatever noble ideas about conservation, the reality is that it will be the cost comparison that is most influential to choice... but I don't see anyone making the right comparison, yet.

Cost of electricity vs gasoline is really about comparing one's existing vehicle to a new one with a high mileage equivalent... it is the operating cost break even point that must be found and the time it takes to get there...

I'm seeing a few ballpark figures here...
50 miles cost $2.98 using electricity=84mpg
35mpg/.3=117mpg
energy equivalent mpg at $4/gal: 104 mpg

Lets say 100mpg is considered...

Few people really run the numbers before replacing a gas guzzler with a new high mileage car. Doing so can be rather alarming, to say the least.

Let's say you already have an old truck that runs fine but gets only 12 mpg.
The new car gets 100 mpg but costs $35,000.
Let's say you drive 1000 miles per month.
And gas costs $4/gal

Driving the truck:
12 miles/gal at $4/gal is 3 miles per $1, so 1000 miles costs $333
So $333 per month to drive the truck

Driving the new car:
100 miles/gal at $4/gal is 25 miles per $1, so 1000 miles costs $40
So $40 per month to drive the new car
Plus the payment on the new car... with a perfect finance deal of 0 down and 0% for 7 years the payment would be $417
So $457 per month to drive the new car

The big question is, how long do you have to drive the new car to reach the break-even point after which you begin to realize savings over driving the truck?

You can already see right away that this point is beyond the first 7 years... the net monthly difference each month is going to be $417-333=$124 in favor of the truck for 7 years... let's see how much further it takes to break even and begin saving money.

The shift in cost of the new car happens when all the payments are finished in seven years. At that point the cost of operating the new car reduces to just $40.

During those 7 years, the $124 per month net difference in favor of the truck over the new car amounts to 84 months x $124 = $10416

So at the time the car is paid off the car has $10416 yet to save in order to catch up with the truck.

Now, after 7 years, only the fuel cost comprises the difference and the car has a net advantage of $333-$40 = $293 each month. The car is now catching up to the truck at the rate of $293 per month.

The car has $10416 to catch up, so at $293 per month it takes $10416/$293=35.5 more months to do so - almost another 3 years.

So, you have to drive the new car for about 10 years just to break even. This is what few people will bother to figure out - here an 833% improvement in gas mileage will begin to save you money only after 10 years of driving the new car.

I used an exaggerated mileage gap ( a gas guzzler vs a dream car priced low), a 0% finance, and did not include insurance, nor the 10 year time cost of money. Running more likely realistic values will just extend the break even point even further...

 

[OmCheeto]

Whatever noble ideas about conservation, the reality is that it will be the cost comparison that is most influential to choice... but I don't see anyone making the right comparison, yet.

Cost of electricity vs gasoline is really about comparing one's existing vehicle to a new one with a high mileage equivalent... it is the operating cost break even point that must be found and the time it takes to get there...

I'm seeing a few ballpark figures here...
50 miles cost $2.98 using electricity=84mpg
35mpg/.3=117mpg
energy equivalent mpg at $4/gal: 104 mpg

Lets say 100mpg is considered...

Few people really run the numbers before replacing a gas guzzler with a new high mileage car. Doing so can be rather alarming, to say the least.

Let's say you already have an old truck that runs fine but gets only 12 mpg.
The new car gets 100 mpg but costs $35,000.
Let's say you drive 1000 miles per month.
And gas costs $4/gal

Driving the truck:
12 miles/gal at $4/gal is 3 miles per $1, so 1000 miles costs $333
So $333 per month to drive the truck

Driving the new car:
100 miles/gal at $4/gal is 25 miles per $1, so 1000 miles costs $40
So $40 per month to drive the new car
Plus the payment on the new car... with a perfect finance deal of 0 down and 0% for 7 years the payment would be $417
So $457 per month to drive the new car

The big question is, how long do you have to drive the new car to reach the break-even point after which you begin to realize savings over driving the truck?

You can already see right away that this point is beyond the first 7 years... the net monthly difference each month is going to be $417-333=$124 in favor of the truck for 7 years... let's see how much further it takes to break even and begin saving money.

The shift in cost of the new car happens when all the payments are finished in seven years. At that point the cost of operating the new car reduces to just $40.

During those 7 years, the $124 per month net difference in favor of the truck over the new car amounts to 84 months x $124 = $10416

So at the time the car is paid off the car has $10416 yet to save in order to catch up with the truck.

Now, after 7 years, only the fuel cost comprises the difference and the car has a net advantage of $333-$40 = $293 each month. The car is now catching up to the truck at the rate of $293 per month.

The car has $10416 to catch up, so at $293 per month it takes $10416/$293=35.5 more months to do so - almost another 3 years.

So, you have to drive the new car for about 10 years just to break even. This is what few people will bother to figure out - here an 833% improvement in gas mileage will begin to save you money only after 10 years of driving the new car.

I used an exaggerated mileage gap ( a gas guzzler vs a dream car priced low), a 0% finance, and did not include insurance, nor the 10 year time cost of money. Running more likely realistic values will just extend the break even point even further...

This all assumes that there was nothing wrong with the old original vehicle.

The second to last car I bought lasted 4 years, at which point I determined that I was incapable of keeping it on the road without a multi-thousand dollar investment. Not only would it not pass DEQ, but nearly every luxury option on the car had failed. I also referred to it as a Chrysler Ebola, as it leaked fluids from every orifice.

I've already pointed out that incredibly modestly powered diesel electric generators(25 kw = 34 hp = $15,000) cost more than a lot of cars on the road. This is a function of the economies of scale, IMHO. This is also probably why electric vehicles are so expensive.

But I'm not an electric purist. I understand the perceived needs of the many outweigh the dreams of a few. So my vehicle of choice, is a hybrid. And if you've missed the news blurb about Leno's Volt, having a hybrid doesn't mean you don't have a potentially 100% electric vehicle:

Jay Leno Drives Chevy Volt 11,000 Miles Without Gas, Nets 2,365 MPG
Gas 2.0
According to Leno, the Volt he bought last year came with a full tank of gas, and since then he has traveled 11,000 miles using less than half a tank of gas. The 9.3 gallon tank isn’t all that big, and Leno’s claim would indicate that he has used less than 4.65 gallons of gas over 11,000 miles of daily driving his Volt in California’s oft-congested traffic. That means, at worst, Jay Leno is averaging around 2,365 MPG.

It just means you have that $15,000 tow-able fossil fueled generator trailer already installed in your car.

And I know that people are biting at the bit to point out that the 2,365 mpg number is a bit disingenuous, which I will not refute, but a pair of emails I received yesterday kind of hint of things to come:

Subject: ... Solar is now on
Date: July 20, 2012 3:02:22 PM PDT

Greetings,

I finally got all the inspections and approvals today and am now generating electrons.

Whoo hoo,

--------------
Subject: Re: ... Solar is now on
Date: July 20, 2012 3:18:44 PM PDT

Congrats! I turned on my system in March and it is totally cool to see my meter putting energy in the grid on a sunny day AND be able to charge my Leaf at the same time . . . charging my car on sunlight

I know these vehicles are currently fairly expensive, and I don't apologize for the fact that I could only afford to buy a brand new non-hybrid gas powered truck 3 years ago, but the numbers to me say, gas should eventually be used, logically.

PattiM, are you still listening? This means if you can't afford to keep both your Silverwing, and buy your Z, just keep your Silverwing.

ps. I'm retiring 3 years early, as I see this whole thing as an incredible business opportunity. 680 dtg!

 

[bahamagreen]

Interesting you mention the Volt...

GM now has a 30 day return full refund in effect on all its vehicles.
The purchase of a Volt qualifies for a $7500 tax refund.
The applicable tax form for claiming the refund does not specify a minimum period of ownership - only that the VIN number be indicated for the new Volt that was owned during some part of the tax year.

One might expect to see a lot of used Volts (less than 30 days) begin to appear on the market.

 

[OmCheeto]

Interesting you mention the Volt...

GM now has a 30 day return full refund in effect on all its vehicles.
The purchase of a Volt qualifies for a $7500 tax refund.
The applicable tax form for claiming the refund does not specify a minimum period of ownership - only that the VIN number be indicated for the new Volt that was owned during some part of the tax year.

One might expect to see a lot of used Volts (less than 30 days) begin to appear on the market.

Well, that really gives the comparison of driving "electric vs. gas" a new spin. It can actually be profitable to drive electrics!

What a delightful scam. I'll email Barry about this immediately.

Thank you.

ps. I decided Barry might be getting too many emails, so I just sent one to my Senator Merkley. He just made a 300 mile road trip in an EV two weeks ago. I figured he'd be receptive to some non Earth shattering input.

Also, according to another website, the 300 mile trip only cost $9.

Yippie!

 

[mheslep]

... Senator Merkley. He just made a 300 mile road trip in an EV two weeks ago. ...

Not much to tout, as the otherwise ~six hour trip was a two day, nine stop trip in that EV. He might have biked the distance in two days.

the 300 mile trip only cost $9.

Or $0 in fuel costs if he biked it. My point is that if one adds ~$150 for a hotel and an extra day's worth of on-the-road meals and amenities, not to mention lost time doing what he could have been doing at the destination, then it doesn't look so cheap.

 

[OmCheeto]

Not much to tout, as the otherwise ~six hour trip was a two day, nine stop trip in that EV. He might have biked the distance in two days.



Or $0 in fuel costs if he biked it. My point is that if one adds ~$150 for a hotel and an extra day's worth of on-the-road meals and amenities, not to mention lost time doing what he could have been doing at the destination, then it doesn't look so cheap.

Only one thing comes to mind:

This is the way it's been done for billions of years. Small moves, mheslep. Small moves.

ps. If we solved every conceivable problem today, the kids would get bored.