Capping cars’ carbon emissions: An exhaust pipe dream?

To begin with, in a report called: “Monthly monitoring of vehicle fuel economy and emissions: Average sales-weighted fuel-economy rating (window sticker) of purchased new vehicles for October 2007 through September 2015” from the Transportation Research Institute at the University of Michigan, for Model Year 2015 automobiles, average sales-weighted motor vehicle fuel economy was 25.3 miles per gallon (mpg), identical to that of the vehicle Model Year 2014 and represents an improvement of 21.64 percent over the 20.8 mpg fuel-economy rating for automobiles in the 2008 model year. A vehicle Model Year runs from Oct. 1 in one year to Sept. 30 of the next one.

Next, it should be noted that for each gallon of gasoline burned via internal-combustion processes, almost 20 pounds of carbon dioxide (CO₂) gets pumped into the air.

So, if you would like to know just how much the CO₂ contribution to the atmosphere on an annual basis just from U.S.-based internal-combustion-engine-powered cars and light-duty trucks alone is, well, check this out: that amount is 3,359,116,287,984 pounds or 1,679,558,143 tons. To arrive at those figures, used is the 2013 average yearly automobile gasoline consumption rate of 656.37 gallons, a total motor vehicle population of 255,885,879 with an approximate 167,955,814,399 gallons of gasoline and diesel fuel consumption total. That just boggles the mind.

To put things in proper context, please understand that to expect that that level of carbon-emissions output from mass motorization appreciably diminishing anytime soon is not very realistic. What can be expected on the other hand is a commitment in the U.S. to improve vehicles’ average fuel economy to 54.5 mpg by 2025. If that happens, as a result, carbon dioxide and other emissions will be cut, for sure. What is not known, meanwhile, is whether or not the diesel-engine-software-defeat-device controversy will have a catalyzing effect in speeding up the process of cars being made cleaner-burning as well as being more fuel efficient. Take some comfort in knowing, however, that cars’ fuel-efficiency ratings have been improving, if but gradually.

Now, assuming flat motor vehicle sales, and assuming also the average 54.5 mpg motor vehicle specification is realized, what will this mean or do in terms of carbon-dioxide-emissions releases from the automobility realm?

In looking at the amount of annual fuel required to provide for in excess of 2.97 trillion yearly vehicle travel miles, assuming an average 54.5 mpg per vehicle fuel economy rating, and assuming an arbitrary per-capita yearly vehicle miles traveled average of 9,363, dividing the latter by the former yields an average per-annum, per-vehicle gasoline consumption rate of around 171.8 gallons. So, with 255,885,879 motor vehicles logging in a single year nearly 3 trillion miles, this works out to a cumulative total 43,960,724,496.8 gallons of fuel consumed. And, that would mean 879,214,489,936.5 pounds or roughly 439,607,245 tons of CO₂ emitted from automobiles yearly. That is a considerable savings from the 3,359,116,287,984 pounds or 1,679,558,143 tons of CO₂, respectively, calculated above. That’s some difference!

Keeping things real

Okay, so in keeping things very real, attaining the average 54.5 mpg fuel-economy-rating will be no easy undertaking; keep in mind that this is a 115.42 percent vehicle-fuel-economy upgrade from what we have now. Can it be done? Absolutely! Whether it is going to be is another matter entirely. But know this: continuing improvement in vehicle emissions reduction is not only possible, it’s also doable.

Also, let us not forget that part of the fuel-efficiency-improvement picture will be more of motorization making use of zero-emissions technologies such as fuel cells and rechargeable batteries, to name just two, and, in the grand scheme of things that means an improved air-quality future.

That all said, it isn’t enough for vehicle manufacturers to produce scads of environmentally friendly or friendlier offerings. The key is, they must be the kinds of automobility devices car buyers actually, really want. The reality is we aren’t quite there yet.

Published by Alan Kandel