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Whats the logic behind hybrids and fuel efficiency?

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dmg

Fri Mar 30 2012, 06:29PM

Registered Member #2628 Joined: Fri Jan 15 2010, 12:23AM
Location:
Posts: 627

This thought hit me this morning, and Im sure most of you see this regularly, rising gas prices, people switching to hybrid/fuel efficient vehicles, you see periodic commertials boasting fuel efficiency and high MPG.

Now here is the part that I don't quite understand, okay cool, these cars cost less at the pump, but is it just me or people overlook the actual cost of these cars? from random makes that do (honda, toyota/scion, etc) these new/recent cars (2008+) cost a fortune to begin with, over 20K at the cheapest and some go as high as 40K, IIRC some go far higher, but I can't quote make/models of my head (canadain market)

So if the original logic is to make a modern economy car thats cheap to fuel, gives high millage, doesn't it make more sense from a financial perspective to buy a low efficiency cheap car (the cheap used beaters that go for 2K-5K)? hell, if your on a budget you can get an old civic that will still do over 30MPG with a bit of work and care.

Even with the far worser efficiency and millage, the cost of driving/maintanance doesn't even touch these newer high efficiency vehicle cost, let alone having to be stuck with a lease/payment plans to barely afford those hybrids.

(If you can afford to buy those cars cash anyways, I doubt fuel cost is a big worry)

Right now I average about 15MPG in the city with my old Subaru, nothing to brag about, but it is sure as hell cheaper to run then the bare cost of the hybrids, so whats the logic behind even buying those cars? I doubt even with rising gas prices my driving costs will come close to exceeding the cost of those cars.

Dr. Slack

Fri Mar 30 2012, 06:53PM

Registered Member #72 Joined: Thu Feb 09 2006, 08:29AM
Location: UK St. Albans
Posts: 1659

If the cost to you of subsidised commoditised fuel is low, and the cost to you of an efficient but pre-mature, so still very costly, niche technology is high, then your pure commercial decision to burn lots of fuel is correct. As I don't recall Spock ever putting it, "absolutely logical Captain"

If we factored in the true cost of burning fossil fuel, the cost of moving SanFranCisco, London and Dehli to higher ground during this century, and stopping or fighting a few wars over land, and once more fuel efficient cars drop to 25% of their present cost through econmies of scale, then maybe your decision would be different.

Spin forwards 1000 years. This fad for digging up fossils, using them and then disposing of them will be seen as a transitory phase. Will we choose to end it in an orderly fashion, or will we continue until forced to end it? Not my call, I'm dead in 20 years, 30 tops.

dmg

Fri Mar 30 2012, 07:04PM

Registered Member #2628 Joined: Fri Jan 15 2010, 12:23AM
Location:
Posts: 627

If we fast forward it and still use fossil fuels, or for sake of argument, cost of electricity should the future of transportation be fully electric (which we will be for the next century I think we will still use fossil fuel for our cars for the vast majority), won't we come to the same argument yet again?

Maybe the figures will be different, but todays high cost efficient cars made affordable in the future, will be obsolete by whatever new comes around then. (which will result in this argument made today, but years from now, regardless what power/fuel source you choose to discuss, chances are it will still not be free, or at least the way to obtain it will involve some investment or cost).

I understand that it is technological advancement, else we will still be driving 20's style cars with meters per gallon, rather then miles, but where does it reach an equilibrium between car cost and operational cost?

Mattski

Fri Mar 30 2012, 11:01PM

Registered Member #1792 Joined: Fri Oct 31 2008, 08:12PM
Location: University of California
Posts: 527

There is something to be said about buying an old used car in terms of efficiency, because you avoid the high resource cost of building an entirely new car. But some people have to buy new cars otherwise the used market would run out of cars :) And that old used car is not the equivalent of a new car... you'll be doing more maintenance and it may not have all the modern safety features, in addition to the worse gas mileage.

So if you are buying a new car, should you go regular or hybrid? I ran some rough numbers and figure over 100k miles I would burn about 3,333 gallons of gas in my Camry versus 2,000 in a Prius. At current CA gas prices that comes out to $5,700 in gasoline saved in the Prius, which is less than what a Prius costs over and above a new Camry depending on features. So to 1st order (well maybe 0th order), a hybrid makes sense at the 100k mile mark.

Some of the pricier vehicles like the Volt cost closer to the $40k mark, but they also have even better mileage. The price of gas will continue rising in the long term because there is a finite supply, so hybrids and electric vehicles will increasingly become good investments.

wrote ...
Maybe the figures will be different, but todays high cost efficient cars made affordable in the future, will be obsolete by whatever new comes around then.

It is always tempting in discussions about green energy and conservation to hope for some clever new technological silver bullet to solve all of our problems (fusion, anybody?), but it is still prudent to try to come up with a strategy for sustainability based on current technology. Overall electric drivetrain efficiency including battery change and discharge, motor driver, and motor can exceed 70%, which leaves less than 50% room for improvement. The main areas we could see a revolution is in the energy density and the cost of energy storage.

dmg

Sat Mar 31 2012, 12:59AM

Registered Member #2628 Joined: Fri Jan 15 2010, 12:23AM
Location:
Posts: 627

I just did some quick math for myself based on that.
So say I will be going over the period of 100K miles on the car like you said, here is what I come up with.

15MPG average over 100,000, would result in 6666 gallons (25230L) of gas consumed.
on average, I pay 1.25$ a liter on gas (94 octane, premium as I have a turbocharged system and anything lower causes engine knock)
so thats roughly 31,537.5$ to drive my car for 100,000 miles, without account of insurance, maintenance etc.

With my current driving style, I pile an average of 10,000 miles a year, so lets say it will take me 10 years to put on that 100K, so the annual gas cost arives at 3153.7$, lets put that number up to 5000$ a year if I throw in insurance (roughly 1500$) and maintenance (much less as I do it myself)

(the insurance is still high due to the nature of the vehicle and some speeding tickets on my name)

In general, Im fairly high up on the payment ladder, due to premium gas and low efficiency, and my choise of vehicle, I wasn't really considering its efficiency too much.

so math says on average it is 262$ a month for gas, I know for a fact its not that high, (I pay about 170-200 a month), but thats the higher end math for you. I do put on some highway miles, and do about 23-25MPG with disiplined driving.

So I see as a long term investment you may save some money with the hybrid, but for short term it might be cheaper off with the older car?

Or is my math WAY off?

Steve Conner

Sat Mar 31 2012, 06:58AM

Registered Member #30 Joined: Fri Feb 03 2006, 10:52AM
Location: Glasgow, Scotland
Posts: 6706

Well, I did the math too, I just bought a car and it wasn't a Prius.

It's unashamedly gas engined, with two large chrome exhaust pipes and a 98 octane fuel requirement. Sadly it's not a Subaru, the insurance was just too expensive.

If you mainly do long journeys, a good turbo diesel can beat a hybrid in fuel economy as well as first cost. An extreme example would be the VW Lupo 3L, which used just 3 litres per 100km, about 70mpg. Of course OPEC bribed VW to discontinue it.

Hybrids really excel in threading their way through city traffic: the regen braking loves the constant starting and stopping, and the combustion engine hardly comes on at all. Most cab drivers in Vancouver use Priuses.

Over here the cab of choice is the diesel Skoda Octavia, because it comes with an unlimited mileage warranty.

Finn Hammer

Sat Mar 31 2012, 12:45PM

Registered Member #205 Joined: Sat Feb 18 2006, 11:59AM
Location: SkÃ¸rping, Denmark
Posts: 741

Steve Conner wrote ...

An extreme example would be the VW Lupo 3L, which used just 3 litres per 100km, about 70mpg. Of course OPEC bribed VW to discontinue it.

Wear and tear forced me to discontinue mine after 10 years and a whopping 458.000 km, more than 11 times round the equator. My new Polo Bluemotion doesn't come close to the Lupo in mileage

Cheers, Finn Hammer

Mattski

Sat Mar 31 2012, 08:12PM

Registered Member #1792 Joined: Fri Oct 31 2008, 08:12PM
Location: University of California
Posts: 527

wrote ...
So I see as a long term investment you may save some money with the hybrid, but for short term it might be cheaper off with the older car?

Precisely. In exchange for high capital investment you get lower operational cost, so it will take time for the payoff to be realized. Buying a new car has lower up-front cost and higher operational cost, buying a used car has lowest up-front cost and highest operation cost.

If you want to look at the value of a hybrid from a more thorough point of view you would also have to consider the opportunity cost of putting your money into a hybrid instead of, say, an investment. Or consider the cost of a loan for the more expensive hybrid.

Diesel cars are not common in the USA, though I have heard good things about their efficiency from the folks in Europe :)

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