What do the rating stars mean?
General Motors has made a huge commitment in time and resources to put the Equinox Fuel Cell Electric Vehicles on the road. Even though it’s initially a limited 100 vehicle release, this controlled experiment to test the viability of hydrogen fuel cell powered vehicles represents a gamble for the company. GM suffered a lot of bad press over the unceremonious demise of the EV1 (its beloved—if doomed—all battery electric vehicles), even a critical movie was made about it. Do they have reason to believe the same reel won’t roll again with this Equinox Fuel Cell Electric Vehicle (FCEV)?
Initial Impression: The WOW factor
It’s hard to miss the statement that General Motors is making with the Chevrolet Equinox Fuel Cell Electric Vehicle. Splashy graphics adorn the side flanks and rear lift gate. Clever arrangement of dashes and Os create a chemical representation of water molecules. H20, which is the sole discharge from the Equinox FCEV's exhaust slots.
It's equally hard to miss the passion this vehicle elicits from people. I was fortunate enough to spend a day with the very engineers who helped design the Equinox FCEV, and I grilled them on topics ranging from the overall vehicle safety to the intricacies of how the hydrogen injectors work. I’ll say this: Each and every one of them was passionate about fuel cells and hydrogen power. I got the distinct impression that these folks consider the Equinox FCEV almost like their own child.
Continued below...
Look & feel: Where’s the engine?
Slide behind the wheel and gaze around; there is no indication of the modern marvel under the hood. It looks and feels like a conventional Equinox—though the sky blue seat fabric would not be my first choice—understandably Chevrolet did that to convey the clean image of fuel cell power.
Turning the key is the first real indicator that things are different. No starter crank, no engine rumble—just the hum of pumps and fans, and the glow of the energy monitor that shows the electrons flowing to the onboard NiMH battery and/or the electric drive motor. And what about that pump and fan noise? Well, it’s there in a regular car too, it just can’t be heard because it’s masked by engine noise. It’s one of those things that’s not noticed until its absence announces itself.
Driving the Equinox FCEV is like driving a regular Equinox. Really. The two most notable aspects are the (almost) total lack of detectable noise, and—perhaps a little unsatisfying—the lack of high end torque. There is no tachometer—its replacement is a kilowatt (kW) meter, so it’s pretty hard to say that torque drops off at X rpms. Suffice it to say that at cruising speed, mashing the accelerator translates roughly into "yeah, I’ll pick up speed for ya, but it’s gonna take a coupla secs." It’s certainly not dangerous—or even atrocious—just not exactly what most of us are used to. I think things will improve drastically as fuel cell drivetrains mature. Fuel cell powered vehicles are still quite a new concept in the grand scheme of things.
Fuel-ability: It’s not the X factor—it’s the H factor
The Equinox fuel cell vehicle has a fuel tank (three, actually)—but it’s not designed to hold liquid gasoline as we are accustomed to. The Equinox FCEV’s three carbon fiber tanks hold a combined total of 4.2 kg of hydrogen compressed at 700 BAR (10,000 PSI). In gasoline gallon equivalents (GGE), 1 kg of hydrogen is roughly equal to 1 gallon of gasoline. Hydrogen flows from the tanks, through injectors, and into each of the 400-odd individual fuel cells within the fuel cell stack. Here the hydrogen is ionized and it’s stripped-off electrons join-up to generate 93 kW of power that both energizes the drive motor and assists in charging the vehicle’s onboard NiMH booster battery. Based on EPA 2008 estimates, the Equinox FCEV gets about 37 mpg (GGE) and has an effective range of about 150 miles. The limited range is really a function of gas pressurization and tank volume.
Presently, the Equinox FCEV cannot wander too far from a hydrogen re-fueling station, and this is the challenge for any hydrogen powered vehicle. It’s not about how the vehicle handles. It’s not about overcoming real or imagined lack of power. It’s not even about limited onboard hydrogen storage. These design obstacles will be conquered with persistence and smart engineering. The most difficult hurdle to clear will be building a refueling infrastructure that puts hydrogen filling pumps in strategic locations that will allow for interstate travel. It’ll take a commitment from private industry as well as support and backing from governments to spend the money and help put the pieces in place.
The Enviro-meter: It’s just clean—no scrubbers needed
This vehicle is 100 percent clean. It’s the nature of the beast. Powering a vehicle with electricity generated by a fuel cell creates absolutely no toxic emissions. The only discharge whatsoever is warm water vapor from the exhaust slots.
Now, some folks would argue that a pure battery electric vehicle would be just as clean—and that is true to the extent that the electricity that charges the battery comes from clean resources (wind or solar). By and large most electricity is still generated from coal and petroleum resources. And, some folks claim that burning hydrogen inside an internal combustion engine is equally clean. While it’s true that the main emission from this setup is water vapor, NOx still forms—any fuel burned in the presence of nitrogen in the atmosphere creates NOx. Presently most of the hydrogen supplies in the world are extracted from natural gas—so that source isn’t completely clean at this point either. However, large scale electrolysis using renewable energy would solve that problem—continued R & D is making headway.
Sure, an electric vehicle powered by renewably generated power is just as clean as a vehicle powered by an onboard fuel cell--both are zero emissions. So where’s the difference—where’s the pay-off? The real benefit of the fuel cell—as infrastructure and storage improve—is the ability to re-fuel just like a regular car and drive interstates. The downside of an electric vehicle is the hours-long recharging process—it will take a major leap in battery technology to provide the same practical range.