energy and emission impacts of advanced vehicle technologies and fuels 1

[josephv]

Hello all,

Good afternoon, I noticed that there are now many threads debating the benefit of hybrid, electric cars and new fuels; as well as their impact on the environment.

FYI

"To fully evaluate energy and emission impacts of advanced vehicle technologies and new transportation fuels, the fuel cycle from wells to wheels and the vehicle cycle through material recovery and vehicle disposal need to be considered. Sponsored by the U.S. Department of Energy's Office of Energy Efficiency and Renewable Energy (EERE), Argonne has developed a fuel-cycle model called GREET (Greenhouse gases, Regulated Emissions, and Energy use in Transportation). It allows researchers and analysts to evaluate various vehicle and fuel combinations on a full fuel-cycle basis."

You can actually download the GREET model and compare different vehicles (it's free):

http://www.transportation.anl.gov/software/GREET/

Here are some sample results:

http://www.transportation.anl.gov/software/GREET/sample_results.html

Using this model there are studies that show that a plug-in electric (with 50% power coming from coal) still has lower CO2 emissions that a regular gas car. But, I don't want to start yet another debate right now. What I wanted to do is share this link with everyone here.

Have a great weekend.

 

[moltenmetal]

jmw: Lifecycle costing is very important to making the right decisions about the environmental cost of ownership of a vehicle. The trouble with lifecycle costing is that the calculations can be very subjective. What do you include in the calculation? What do you exclude? And how do you value the "externalities" in the calculation? The impacts to others that aren't easy to assess a monetary cost to?

Just looking at purchase price for energy: without taking the time value of money into account, at Canadian gasoline prices averaged between date of purchase and date of retirement, my Honda Civic hatchback will just barely consume its purchase price worth of retail gasoline over its reasonable lifetime (300,000 km driven over ~8-10 years). So unless the energy that the auto makers, steel makers etc. are using is vastly cheaper than what I'm paying for gasoline, it's doubtful to me that there is as much embodied energy in my vehicle as it will consume over its lifetime.

A Prius has only twice the purchase price of my Civic- granted, Toyota is reportedly subsidizing their purchase price somewhat at present. And the Prius' purchase price is similar to that of an SUV- maybe a little cheaper depending on how grandiose an SUV you purchase. The Prius will consume less gasoline than my Civic throughout its service life. The Prius's service life might be less than that of an SUV, but I sincerely doubt it's half the service life of a typical SUV. Given the economics of the situation, it's questionable to me that a Prius's lifecycle energy input could be higher than that of an SUV which consumes vastly greater quantities of gasoline per unit distance travelled.

So the methodology of the study used to determine that the Prius was a much worse "environmental" choice than most SUVs would be highly subjective.

As to whether or the "hybridization" of SUVs is a net benefit or cost to the environment, that's another matter. In these cases, the hybrid feature merely compensates for performance lost by shifting to a somewhat smaller engine- asuaging the guilt of the SUV-purchaser in the process. The jury's still out on that one.

 

[EdDanzer]

In all of the discussions about vehicle size and cost in environmental terms, no one discussed cost per passenger/load mile over the life of the vehicle. There should be a similar value for mass transit.
All vehicles should have a thermal efficiency rating at various loads and speeds. This would provide a better way to determine what vehicle to purchase.

Comokid, before you judge all vehicles at first glance remember the first owner of a pickup may not be the one who uses it to its fullest potential. Many small businesses will not buy a new truck just to trash for work. Look at most trucks driven by painters.
The distance you drive to work, the number people you transport to non work functions, and resale value should influence your vehicle choice also.
If you want to reduce energy wasted, tax people for leisure time, it consumes a lot of energy for little relevant value.

Having listen to a couple of recent presentations presented by our National Labs, don’t stake you life or income on their information. Some of their assumptions are bias, not well documented by actual collected data, and they leave out some important details.

If you expect someone working for a large company or lab to develop technology to save your ass, you may want to kiss it good by now.

 

[jmw]

Moltenmetal,
what you are really saying is that we should be very careful as to how much credibility we give the data, any data (no matter how well it fits our own sceptical view point) until the methodology is demonstrated to be valid and that is right.

However, that it is not to say that the data is necessarily wrong nor that this set of conclusions should be considered less valid simply because your own estimates are less critical of the Prius.
Excuse me if I put it badly, and I don't think you were suggesting that your own valuation was anything other than an order of magnitude check, since I am sure you have not done the same research nor had access to the same data.

But:
It will be interesting to see how well these results compare to the results presented by Argoyne.

Secondly, whatever complex subject we chose to consider the nature of the evaluation is always pretty controversial e.g. when they work out the unemployment figures or the cost of living index.
Most important is that measurement made is appropriate to that which we are interested in and that on a year by year basis it is consistent.

Quite clearly simply declaring the Prius and its ilk as environmentally friendly simply because they are responsible for less emissions in use but neglecting the energy used to produce them and dispose of them is far less satisfactory (downright misleading) and the attempt to assess the dust to dust energy use is obviously more valid.
I have no doubt that if there is anything at all controversial in how one set of figures was derived that we will hear about it in due course.

In the study I would be surprised if the "cost" is interpreted as you suggest since obviously a gallon of petrol in the UK is vastly different in cost to a gallon in the US (even after adjusting between US and UK gallons) and that we should treat this as an "Index" in which case all vehicles are calculated based on the same energy used. Of course, this needs to be established but I would be surprised if there were any obvious fallacies in the cost per mile index shown.



JMW

http://www.ViscoAnalyser.com

 

[duck0601]

Regarding the development of Hybrid SUVs. What is the problem with this? The engines are built to accelereate the vehicles, not to sustain speed. If I have an electric motor, I can use it to get my speed up to highway levels, the use my smaller engine to keep me going at the speed I need. I save gas. If I also use some of the other fuel management techniques available, e.g. cylinder deactivation, I can have a fuel efficient vehicle that can tow my trailer (caravan, I believe, to you Brits) in the summer, carry my wife and three kids to visit Grandma and carry a sheet of plywood home for those inevitable projects. All three of these activities are difficult or impossible with a Prius. My SUV would also double as a commuter, because I can't afford to have a second vehicle just sit in my driveway.

No guilt to assuage, just the desire to have a vehicle that meets my needs.

Chris

 

[moltenmetal]

duck:

If the people who claim that a Prius is a poorer environmental choice than an SUV on a lifecycle environmental impact basis are correct, then you're far better off with a conventional SUV than with a hybrid SUV- and you're far better off with one SUV than with two vehicles to meet your range of needs. Their argument seems to be that the embodied energy of a hybrid vehicle, "cradle to grave" so to speak, must be totally overwhelming relative to the fuel energy the vehicle will consume throughout its useful life, otherwise they couldn't come to the conclusion that they seem to. I dispute the validity of the conclusion- it flies in the face of basic economics as well as violating my commonsense.

Sure, jmw, my back of the matchbox calc is an order of magnitude check at best- it's pretty simple arithmetic. But it's very tough to imagine how people could sell me something which is much cheaper than the energy ALONE used to produce and dispose of it- that sets a limit on the embodied energy in the product. Last I checked, the most knackered of vehicles had a salvage VALUE rather than a disposal charge, because some of the embodied energy (materials recycling value) in the vehicle can be recovered by the scrap dealer. Do the arithmetic. If the basic dollars and cents don't add up, the conclusion is pretty tough to support- unless there's some major subsidy for manufacture that I'm missing entirely. Perhaps Greg Locock will chime in and correct me.

Hey duck- there are people who actually need SUVs. I'm not disputing that. I'd suggest they're probably 5% of the people who currently own one, tops. Frankly, I don't want your choices, for vehicles or otherwise, to be my business, period. I don't care if you feel guilt about the consequences of these choices, or don't, because I can't depend on your "feelings". Until we both pay the full and fair cost of fuel, your choices unfortunately do become my business, because I bear part of their cost in the form of all the externalities generated by fuel production and consumption that do not show up in the cost at the pumps or the cost on the showroom floor. Once all fuels and other energy sources are burdened with something approximating full lifecycle costs, including charges to deter the generation of these externalities, your choices once again become entirely your own.

PS: I've hauled most of the materials for a major renovation of my home either in or on my Civic hatchback. All you need is some imagination, a chunk of rug and some decent compression straps. Anything I can't haul safely, I have delivered: if it's too big for me to haul, it's usually a big enough order that delivery is free of charge anyway.

 

[Comcokid]

California auto emission laws are more stringent than the EPA requirements and put emphasis on electric vehicles and vehicles with less emissions. California has also required individual auto manufacturers to meet future goals or not to sell anything in California at all.

As such, the Prius has a place - in California or other metropolitan areas with high pollution. A Prius driven in San Jose does what is suppose to do - emits less where the vehicle is being driven. It does this by spreading it's carbon footprint over a wider area, especially if you carge the battery off the power grid as some do.

Development of hybrid vehicles does help move to bring some new technologies (new battery technologies, new electronic motor controls, engine run-on-demand, etc.) into real world use. However, the Prius, and other hybrids as they currently exist, do not represent the ultimate answer - just the latest environmental fad. They are a fad because for the same size (but much lower weight) you could have a non-hybrid vehicle with greater MPG requiring less energy to manufacturer. Hybrids must become smaller and lighter to achieve better efficiency. But buying habits in the US would doom a smaller lighter hybrid.

This brings us to the main issue. Unless US buying habits change towards having smaller cars, then any future technology improvement will only serve to keep US drivers driving larger, heavier vehicles at the same MPG as today, and we will realize no overall improvement in fuel consumption or pollution.