Energy cost of manufacturing small car 2

[PTwizz]

Despite some time spent searching the web, I have been unable to find any figures for the cost, in terms of energy consumption, CO2 output etc, of manufacturing a new small car.
The question arose out of a discussion in which it was suggested that I should replace my 1966 Landrover with a modern, small, fuel effecient car. Given that I use the Landrover for less than 3,000 miles per year, I suspect that a new car would take more than it's lifetime to recoup the energy used to produce it.
I suspect also that many people are being wrongly persuaded to replace their ageing cars on grounds of fuel effeciency.
Can anyone direct me to any source of relevent data?

 

[safetydan]

One way to figure it is energy costs associated with manufacturing account for 2% of net revenue. If you were going to buy a new car for $15,000, the energy associated with producing that car cost about $300 per car. You can also figure you old landrover was produced in a much more inefficient time, using numorous hazardous materials. Nearly all cars produced today have to comply with the EU's ELV program to eliminate hazardous materials from vehicles, as well as make them 85% recycleable by 12/31/06 and 95% by 12/31/10.

You can go as in depth as you want, but if you simply don't want to buy a new vehicle, then don't.

 

[GregLocock]

The rule of thumb used to be that the total energy cost of building a car was about equal to a year's worth of fuel, at typical mileages. However I never saw the calculation, it is surprisingly low in my opinion, although I guess with recycling of aluminium and plastics nowadays it is a bit more believable



Cheers

Greg Locock

Please see FAQ731-376 for tips on how to make the best use of Eng-Tips.

 

[patprimmer]

2% sounds incredibly low.

My rough calcs on Greg's rule of thumb is about 10% of a new car cost, and that still sounds low.

I guess it depends on whether you count the power bill for the manufacturing plant as the cost, or whether you count the total energy cost on all components and materials, from the lights in the showroom to the energy required to make and transport the mining equipment for the metals and the oil used to make the plastics, fabrics and coatings.

Regards

eng-tips, by professional engineers for professional engineers
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[GregLocock]

http://answers.google.com/answers/threadview?id=433981

Cheers

Greg Locock

Please see FAQ731-376 for tips on how to make the best use of Eng-Tips.

 

[tbuelna]

The Hummer H3 is currently more energy cost efficient than a Toyota Prius.

Here's a quote:

"In fact, according to a new study by CNW Marketing Research in Bandon, Ore., the Hummer H3, in terms of dust-to-dust energy costs, equates to $1.95 per mile—while the Toyota Prius and Honda Civic Hybrid are almost $3.30 per mile."

Here's the link:

http://www.hybridcars.com/environment-stories/dust-to-dust-energy-costs.html

 

[GregLocock]

That study isn't exactly unbiased. There's some very strange differences in there for very similar cars.

Cheers

Greg Locock

Please see FAQ731-376 for tips on how to make the best use of Eng-Tips.

 

[PTwizz]

Star for Greg's link to google answers. Just the kind of data I was looking for.

Thanks to all who have replied.

SafetyDan; I was looking for practical justification to replace the Landrover, but I can't justify it economically (costs me about £700 per year to run, including fuel, insurance, repairs etc.) It now appears that I can't justify it ecologically.
Now, if someone would produce a 350Kg plastic bodied space frame with a 40HP turbo diesel for £5k......

Pete.

 

[safetydan]

Pat, you have to look at overall costs. If a vehicle were priced at $15,000 and the energy costs were 10% then 1500 of every car went straight to the utilities at all levels. That would be increadibly high! You have to remember all of the energy costs (electricity, natural gas, transport fuels) are on scale. Just because the steel company spends a lot of money to refine and cast the metal, it doesn't mean it can throw all the price onto one piece.

The largest cost for almost every company is labor. The second highest cost is for materials, but those materials highest cost is also labor, then other raw materials, with the cycle continuing all the way into extraction of the raw materials.

I have worked in the auto manufacturing sector for a while and if we were having to pay 10% of our total revenue for energy usage, we would be out of business. 2% is also high, but I needed a safety factor.

 

[CristobalMiller]

I am wondering how much the increase of the price of electricity or fuels would have on the cost structure of car manufacturers. How much energy cost account of the total cost of producing a passenger car? How much is assembly energy cost? I saw a quote in this forum of 2%, where this estimate come from? That is that include the energy embeded in the production of materials or parts?Could anyone point me to this infomration?

Thank you.

 

[BrianPetersen]

The 2% might be the utility bill for the manufacturing plant, but surely it can't include the energy that is "locked" into the materials themselves.

Plastic is basically like oil, except the energy content is even more, because of all the processing that goes into making the monomer and then all the material handling. Most of this is not made from recycled materials.

Aluminum and steel are also rather energy intensive if you include the coal, electricity, etc used in producing them. Recycling helps a lot but there is still a lot of heating up, melting, etc.

I'd make a moderately unscientific first guess that the amount of oil-equivalent that it takes to make a car, is order-of-magnitude equal to the weight of the car. (Plastics overrepresent, metals underrepresent but only if recycled materials are used.)

On that unscientific basis, 3000 lbs is probably 400 gallons, or about $1000 - $1200 at retail prices. The 10% cost basis, including all energy inputs for all materials traced all the way back to the oil well, doesn't sound too improbable to me.

 

[drwebb]

'It now appears that I can't justify it ecologically.'

Don't forget that CO2 isn't the only emission. Your hydrocarbon, CO and NOx footprint is all out of proportion to the miles driven. So the world will be cooler in 50 years because of the Rover, but your local air will be more polluted this year.

 

[PTwizz]

DRWEBB - You are, of course, absolutely right in that there are far more emissions involved than just CO2. I suspect that this is also true of the manufacture and subsequent recycling of much of the material used in modern vehicles.
If it comes down to a balance between short term local pollution vs. long term global pollution, I would have to hold the long term view.

 

[RossABQ]

I doubt that the percentage of overall production cost are based on sales price, they are more likely based on production costs. Thus it would be 2% or 10% (depending who you believe) of Ford/GM/Toyota's bare cost.