hybrid math

[Newz2000]

Just doing a little math...

Lets say I wanted to replace my wife's car with a new car. She currently gets 22mpg. The new camery hybrid gets 37mpg. She spends about $100 /month on gas.

So how much money would she save on gas by switching to a hybrid?

I've attempted the math a few different ways and don't get what I would consider stellar returns. ($2,400 over 5 years)

On a side note, I'm semi-serious about this... my new job will have me working from home. For years we got by with one car and only purchased a second car since my current job required commuting.

I'm thinking it would be fun to convert my little Corolla, our second car, to a plug-in EV. Has anyone seriously looked into this and tried to figure out whats involved? My motivation would be a conversation piece and a fun project.

Honestly, I probably won't do it, but it's fun to think about. I know it's more complex than it sounds, but I'm curious if anyone knows where you go to get the parts and how to calculate what the actual cost will be.

[Chris Smith]

Every gallon of gas not going east is less power for a politician, less lost lives, and less hidden costs wasted by DC and never explained to you.

Did you really think the money you pay for any object contains all the hidden costs of reality?

[philba]

your math is fine, reality is problem. no, the hybrids and alternative fuel vehicles simply are not cost effecient. I personally believe that gas will reach $10 a gallon by the end of the decade. even then, the payback on your hybrid isn't there. the era of cheap energy is over, even in the face of alternate fuels like ethanol.

however, I believe that encouraging highly fuel efficient vehicle production is a very good thing so you should go ahead a buy that hybrid. that will increase demand and thus increase production.

[gerty]

Have you priced car insurance for a hybrid? My wife and I spoke to a woman who had parked hers next to us. We asked how she liked it and she said she was satisfied with the car but the insurance was over twice as much as her previous car. She was told that replacement costs for the 'parts' were going to be very high should she have a wreck..

[jwax]

I've never tried making gasoline, but ethanol........OH YUS!

[jollyrgr]

The ROI for a hybrid is between 10 and 12 years.

Now let's do some math....
(This may seem a bit over drawn but not everyone understands how to do these types of problems.)

You say 22 Miles/Gal and $100/Month on gas. For sake of argument, lets say gas is $3.00/Gal. (At $100 a month, this is $1200 per year on gas currently. More on this figure later.)

She buys and burns 33.3 Gal/Month (Divide $100/Month by $3.00/Gal)

At 22 Miles/Gal she drives 733 miles/month. (Rounded). This is 8796 miles per year....Lets call it 8800 Miles/year.

Solve for the hybrid cost per year using the same driving habits and gas price. 8800 Miles/year at 37 Miles/Gal. Divide 8800 by 37 and get about 238 Gal/year of gas bought and burned. Using the same $3 gas cost gives $714 a year on gas. Subtract the two different costs for gas per year gives a savings of $486 dollars a year saved. Multiply out for five years and you get $2430 saved over five years.

Your math is spot on.


Chris points out something very important. Places like California want to start charging drivers by how many miles per year they drive. I believe they are doing this in the UK already. They put a GPS in your car and keep track of how far you drive. This is supposedly because the gas saving vehicles mean less revenue from gas taxes. But the lower gas users still cause the same amount of damage to the roads as the higher gas uses. So everyone must pay their fair share by paying how many miles they drive.

[philba]

I've never tried making gasoline, but ethanol........OH YUS!

Yeah, I know how to make ethanol, too. but it just never seems to make it my gas tank...

[hlreed]

You don't buy a hybrid car for milage alone. It is that electric and gas have complementary torque properties. They are smooth, with constant torque at every speed. The miliage is an extra.

[Will]

Re " Your math is spot on"
I don't think so - Ax far as I can remember the cost of a Prius is something like $10,000 more than an equivalent car. The present value (PV) of $486 per year for 10 years at 5% is something like $3,865 i.e. PV of 10 year annual savings total of $486 - The net cost (Not saving) is thus $10,000 - $3,865 = $6135 Cost or Loss ?

[Will]

Friends,
I highly recommend that y'all look at the two web sites name by Virand in " Would you buy one " At this point I'm not going to say anything for or against but once these are read they will probably result in a couple of hundred posts on this forum.
Hint - Someone else is achieving high efficiency by compressing air and then allowing it to re-compress using the mechanical energy of expansion !

[Newz2000]

Re " Your math is spot on"
I don't think so - Ax far as I can remember the cost of a Prius is something like $10,000 more than an equivalent car. The present value (PV) of $486 per year for 10 years at 5% is something like $3,865 i.e. PV of 10 year annual savings total of $486 - The net cost (Not saving) is thus $10,000 - $3,865 = $6135 Cost or Loss ?

Well, we weren't calculating into it the cost difference in the cars, just the difference in fuel economy.

By the way, I'm not buying a new car... I bought one and unless I hit the lottery (I don't play the lottery) I won't buy another. 2 - 3 years old will be the closest I come to a new car. I just wanted to know if a person could realisticaly use the gas savings as a reason, or if it all came out to your desire towards eco-frienliness.

I'm surprised no one chimed in on the EV conversion. That's actually much more interesting to me.

Also, why don't you hear of people making their own hybrid car by doing an EV conversion then attaching a lawn mower motor and an alternator to charge on demand? Seems like you should be able to increase your distance by 50% that way and still get something like 90 mpg (or maybe in this case it should be watts per gallon). A few months ago I asked about the horse power needed to run an alternator and I think we decided that 3 HP of motor could generate 90 amps @ 12v (going from memory). Of course EVs run at higher voltage, but I've seen plenty of articles on increasing the output voltage of standard alternators.

As a matter of fact, you could probably use the alternator as the load for the electric motor and simply use the batteries as a buffer for when you climb hills and need to go fast.

It would be kind of fun to pick up a used S10 and do an ev conversion on it.

[L. Daniel Rosa]

The new camery hybrid gets 37mpg.

That's pathetic! Two cars I've owned from the '80s got that on frequent occasion, and one even had an automatic transmission. One truck got 53 one day on back country highway with 500 pounds of junk in the back.

What I'm driving now doesn't do as well, but for 37 I'm not motivated to get anything new.

[Chris Smith]

Lets keep paying the arabs for oil, not needed and subsidized by morons in the WH?

Nothing like a hidden cost to make the mind quiet?

Filler up pleaze?

[dacflyer]

i cannot rember where it was on the web, but it was a site that had tons of cars of all sorts that were converted to EV's , i was suprised of it, and some were elaborate !
i even saw my GEO Metro converted to EV. it had a DC-9 electric motor in it..

but i still like my metro as is for now..it gets 40 something to the gallon.
it a 3 banger

i'd love to have an engineer hack it to put in a harley engine one day..not that would be giving a whimpy car some testerone !..heeheee

i also seen at a tractor pull, a guy had taken a 8 cyl. engine and sawed it down to 2 cyl. and it got 70mpg in a chevette.. i was drooling in amazement...

[John Brown]

Places like California want to start charging drivers by how many miles per year they drive. I believe they are doing this in the UK already.

I don't know where you heard that, but it's not true.
We do have a "congestion charge" in central London (and in some other cities, I believe) and we have a at least one stretch of toll road.
We also have a graduated vehicle tax system that is supposed to discourage people from buying big gas-guzzling SUV's, but the difference is so minute as to be laughable, and the sort of people who spend £50,000 on a 4WD Mercedes just to drop one kid off at a school a hundred yards from home aren't going to be put off by having to find an extra £50 a year.