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EPA Proposes Grading System For Car Fuel Economy
suraj.sun writes with this snippet from CNET:
"The EPA and Department of Transportation on Monday proposed a fuel economy label overhaul to reflect how electric and alternative fuel vehicles stack up against gasoline passenger vehicles. ... The changed label, mandated by the 2007 energy law, includes the same information on city and highway miles per gallon and estimated driving costs based on 15,000 miles a year now available. But the new labels add more comparative information, rating cars on mileage, greenhouse gas contribution, and other air pollutants from tailpipe emissions. That means that consumers can look at a label to see how one vehicle compares to all available vehicles, rather than only cars in a specific class. One label proposes grades, ranging from an A-plus to a D. There are no failing grades, since vehicles need to comply with the Clean Air Act."
Just how stupid do you have to be to need a giant letter grade on a car? I hope that version doesn't fly.
a,e,i,o,u and sometimes w and y (at be if of up cwm by)
They already have a 1 to 10 scale on the stickers, how is that any more difficult than an A+ through D system?
think of the people who make 20k/year and can't replace their aging clunkers, but they still need to get to work.
The CO2 emission numbers would be misleading for battery electric and plug-in hybrids because it only states the tailpipe emissions.
Example... A battery-electric vehicle may use 34 KW/h of electricity per 100 miles. According to official data, in the USA, about 0.6 Kg of CO2 is emitted for every KW/h of electricity consumed. So for every 100 miles, about 20 Kg of CO2 is released into the atmosphere. So the data should state that 200g of CO2 is emitted per mile, not the 0g it currently states.
Ignoring other sources of CO2 emission and only looking at tailpipe emissions are misleading for technology which does not have a tailpipe. For example, a battery electric vehicle which uses 40 KW/h of electricity per 100 miles would release more CO2 into the atmosphere than many small gasoline vehicles.
No sig. Move along - nothing to see here.
Most people do drive alone, even when their car can hold 7 or more people. I ride my motorcycle in to work every day and every day I drive past cars that could carry five or more people and if they were they would be as economical as my bike but the most they ever have is two people and that is rare. If people really wanted to be environmentally friendly they would stop driving around in big tin boxes (and fewer of those around would make the roads a lot safer for those of us on two wheels anyway).
"I have the attention span of a strobe lit goldfish, please get to the point quickly!"
battery-electric vehicle may use 34 KW/h of electricity
That IS bad. After only 3 years of engine-time, you'll need a full Nuke plant to power just *one* of those.
per 100 miles
Criminey! Assuming it averages about 50mph, that means it'll only take 23 hours to require a 1GW dedicated power plant, and it only gets worse from there!
Can you be Even More Awesome?!
A might need 2.5 gallons/100mi and Car B needs 3 gallons/100mi, but that tells you less about the actual mileage (40 vs. 33.33).
Only because you are used to thinking in terms of distance / fuel volume.
http://michaelsmith.id.au
Only because you are used to thinking in terms of distance / fuel volume.
Fair enough, but it doesn't answer the fact that the math with GPM is easier.
Do you mean this bit?
With gal/100mi, it's more complicated to figure out how much gas you need to go X miles
If I want to go 200 km and my car uses 10 litre/100km then I need 20 litre. Seems simple to me.
http://michaelsmith.id.au
With gallons/mile, fuel efficiency is linear instead of inverse-linear.
so do the L/KM -> KM/L conversion once, stick it on a sticky note, and use it when you need it. But L/KM makes comparing trip costs(what most usually do, think: "to work", "to inlaws", "to bar") not require any gymnastics.
All of the above was encrypted with a Quad ROT-13 method. Unauthorized decryption is in violation of the DMCA.
If you are driving 100 gallons, however, switching from the corolla to the prius gains you 1700 miles, whereas switching from the hummer to the land rover gains you 400 miles.
Since most people want to know how often they fill up their tank, and know how far they drive on a normal commute, this method is much easier to determine how much money they save. Most people don't care how much gas they save (and really, why should they), because if they tripled their gas usage but saved $1 in total, they would do it.
However, the mere fact that a coffee machine or a breadmaker is safe doesn't actually make it any use for making coffee or baking bread - in fact, in the UK, makers of nonfunctioning "water treatment" products market them as WRAS approved - which is purely safety testing.
Any commercially sponsored test is flawed. Did you ever see a car magazine give a BMW a bad review? Usually they give critical reviews of second tier manufacturers or small cars, which have near-zero "marketing" budgets, and criticise very expensive cars (that their readers can't afford and whose makers don't advertise with them). I'm happy to pay taxes to an organisation that won't go out of business by telling the truth.
From scarped cliff or quarried stone she cries "A thousand types are gone, I care for nothing, no not one."
With gallons/miles you do not have to do a division, but a simple multiplication to get the necessary gas to drive X miles. Programmers of all people should now that multiplication is far easier to do...
75 miles @ 8 gallons/100miles? 0.75*8=6 gallons. ... err... 150/25... 30/5... 6 gallons.
75 miles @ 12.5 miles/gallon? 75/12.5 =