BF2S Forums United States EPA ratings need upgrade for new crop of vehicles

Instead of Miles Per Gallon (MPG - gallon being an English unit), we really should be doing a Miles Per Kilowatt Hour (MPK - kilowatt being an SI unit).

We get KWH charge on our electric bills, so why not just rate these vehicles using the number of miles they can get per kilowatt hour???

The price of electric varies too widely to convert the number into the equivalent MPG value - its misleading and its politically motivated I believe.

The Obama administration I believe is misleading people to think that these vehicles are really 5-10x times better than their current vehicles.

They are better, but using the MPG rating is misleading and in my view dishonest.

Besides 50% of our energy in the United States is made using Coal.  And 40% of electricity is lost due to inefficiencies in our transmission lines.

FatherTed wrote:

because MPG is something people can quantify?

But if said device doesn't use gas or only partially does, I think we need a new metric.

km/kWh Would make the most sense, MPG is indeed irrelevant.

Some countries quote gCO2/km which is ideal, and blows away some of the apparent advantage of diesel.

In the long run reckon you'll sign up for an electricity contract when you buy the car.

SI units would make much, much, much more sense (imagine trying to solve F = ma with imperial units... funny constants here we go).

gCO2/km is smart, kW/km is also smart. (it depends what you need it for, the first is more an environmental measure, while the second is a more general or economic measure. Both would be best tbh)

Dilbert_X wrote:

gCO2/km would be pretty hard to figure for an electric vehicle - unless a fixed value is taken for gCO2/kWh, but would at least be directly comparable with fossil fuel equivalents.

Plus it wouldn't exactly be accurate either.

There are far too many variables to give an accurate representation of the CO2 output of a vehicle. Hell, just working the amount of complete vs. incomplete combustion (the very simplest variable) is difficult in itself.

But as an 'arbitary' and practically meaningless measure - i.e. as a comparative measurement - it could be useful.

ghettoperson wrote:

Spark wrote:

SI units would make much, much, much more sense (imagine trying to solve F = ma with imperial units... funny constants here we go).

gCO2/km is smart, kW/km is also smart. (it depends what you need it for, the first is more an environmental measure, while the second is a more general or economic measure. Both would be best tbh)

I would say kW/km or kW/M depending on where you're from. gCO2/km would be helpful, but is largely irrelevant to the consumer.

Again I wouldn't be surprised to see both. I agree with you KW/KM has much more practical meaning and usefulness but gCO2/KM could see common usage as a 'marketing' tool as one of those catchy figures designed to improve a car's standing in the eye of the environmentally minded consumer.

Mekstizzle wrote:

Why do all of these cars have the same horrible Prius style rear end

It has kind of a bubble butt but what ever. The interior is sleek though I have to say.

Those headlamps are a little off. They're good on say..that Merano, but those are weird.

Dilbert_X wrote:

There are far too many variables to give an accurate representation of the CO2 output of a vehicle. Hell, just working the amount of complete vs. incomplete combustion (the very simplest variable) is difficult in itself.

To get the figure fuel consumption is measured very carefully on a rolling road running a specific program, fuel in and exhaust out are measured precisely.
Modern cars also control their mixture very well - or the catalyst gets damaged.

So the CO2/km figure should be pretty well dead on.

The round butt is to reduce induced drag.

Oh?

Wasn't aware of that.