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Apr 12, 2012

Bells and Whistles Won’t Unlock Cost-Effective Auto Efficiency


As the New York auto show continues this week, Rocky Mountain Institute is encouraged by a growing number of efficient and electric models being introduced by automakers. But today's “bells-and-whistles” approach to achieving better fuel economy is not enough to cost-effectively unlock the full efficiency potential of electric vehicles.

Reason 1: Fitness first

Automakers can either stay at the mercy of consumer response to oil volatility or they can position themselves for long-term advantage. Electric vehicles are expensive in large part because batteries are. But putting an electric powertrain in a traditional body is a bells-and-whistles approach—and an expensive one at that.

By first shifting to ultralight but ultrastrong autobodies made of advanced materials, propulsion systems can be smaller, lighter, cheaper, and more cost-effectively electrified. Automakers can thus deliver a more competitive product regardless of what is happening with gas prices, and regardless of which powertrain technology they ultimately adopt.

Reason 2: The value beyond cost savings isn't always sold

Reduced total cost of ownership is not the only benefit of an efficient car. Automakers can market lightweight vehicles in a way that emphasizes performance in addition to efficiency. Vehicle lightness, particularly of the magnitude possible with advanced materials, allows better acceleration and improved noise, vibration, and handling characteristics, particularly if combined with electrified propulsion. Many customers will pay a high premium for performance—and an overall better driving experience—regardless of efficiency. It's no coincidence that BMW, a first-mover in many of these areas—offers the “ultimate driving machine.”

Reason 3: Thermal comfort is under-addressed

Air conditioning in U.S. autos burns 170 million barrels of oil per year—5.5 percent of all U.S. consumption. Running a vehicle air conditioner at full blast is equivalent, in terms of energy consumption, to driving 35 mph. For a typical vehicle, this translates to a 26 percent reduction in mpg. For an electric vehicle, it reduces range by 36 percent, and heating has the same effect. By addressing thermal comfort in innovative ways, automakers can improve vehicle fuel economy and range, enhance passenger comfort, and reduce their own costs by downsizing air conditioning and heating systems.

More information on RMI's work in transportation—aimed at getting the U.S. transportation sector off oil by 2050—is available here.

Greg Rucks is a consultant at RMI, where he has worked to develop energy-efficient design solutions for clients in the industrial and automotive sectors. Prior to joining RMI, Greg spent four years working for Boeing on structural optimization and lightweight design for the 787 program.


Showing 1-4 of 4 comments

April 12, 2012

I actually have an electric car and I love it. We I get 7 miles per kilowatt hour which we calculated to be the equivalent of 292 miles per gallon based on our current electric rates and $3.75/gallon at the pump. Gas prices are actually higher than that here in Nashville, and we have a grid-fed solar array on our roof and sell our excess power back to the utility. So really the economics are considerably more favorable for us than that.

It does get hot here in Tennessee, but I only felt the need to use the A/C a few times last summer. Heat was more of an issue because you need it to de-fog the windshield and windows. But really it didn't add up to much energy usage. I tended to put the defrost on when I was at a stop light and then turned it off when I was traveling.

Another thing people ask me all the time is what kind of impact driving an EV has had on our electric bill. The answer is ... none! At the same time we bought our EV last year we had TVA conduct a home energy audit and we had E3 Innovative do our home efficiency and insulation -- caulking and sealing the ductwork, insulating, etc. The result has been we're using less electricity this year than last year, when we didn't have an EV. I'm still amazed at that turn of events.

I passed a gas station charging $3.98 for unleaded the other day. I'm so grateful that this is a headache I don't have to deal with! Also: no oil changes. And the Leaf is a great car.

April 18, 2012

WRT #2 - I own a Leaf and my favorite feature above all else is that my bluetooth handsfree has excellent sound quality. Because there is no chassis/engine noise, my voice is clear on the other end of the line.

It is incredible.

April 18, 2012

I also have a 100% Electric LEAF and get 5.4 miles/kwh on the dash, the on line record is over 8 miles /kwh.
We also have solar on our home so we drive for free in the car but bicycle as much as possible. Our home makes more than we use for the home and car. We only charge Off Peak at night so we help use the excess energy in the GRID they may dump if it doesn't get used.

Electric vehicles are 80% efficient and even regenerate while going downhill and stopping. The small light Mitsubishi MiEV is even more efficient since it's a little smaller and lighter.

Plugin vehicles can also V2G Vehicle to GRID adding storage to excess eneregy and regulationg the GRID not to mention providing back up to your home, read about it at V2G-101.com

April 18, 2012

RMI needs to take a serious look at the engineering realities behind its EV advocacy. 1) battery energy density has remained nearly flat for over a decade, despite large investments; 2) there are not enough rare earth reserves on the planet to make all the motor magnets and other components needed for an EV fleet; 3) super light composite vehicles that could make electric drivetrains feasible would have to mix it up with much heavier existing vehicles during the deployment of the new type of vehicles. Regardless of how well built these are, this will present safety issues; 4) no amount of lightening of vehicles eliminates the fact that the things we require vehicles to carry are heavy, so the problems of energy density mentioned above are probably prohibitive, and will perpetuate the heavy / light vehicle mix that poses significant safety issues.

I look to RMI for real prescriptions for solutions that work. The work on EVs strikes me as shading toward boosterism. I recommend that folks read John Peterson's "Time to Kill the Electric Car," August 2011.

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