Honda's second-gen Clarity Fuel Cell is so clean you could drink from it

The Clarity Fuel Cell's only tailpipe emission is water so clean that I could drink it. No, I didn't actually drink it, but I could if I wanted to.

Antuan Goodwin
Antuan Goodwin Reviews Editor / Cars
Antuan Goodwin gained his automotive knowledge the old fashioned way, by turning wrenches in a driveway and picking up speeding tickets. From drivetrain tech and electrification to car audio installs and cabin tech, if it's on wheels, Antuan is knowledgeable.
Expertise Reviewing cars and car technology since 2008 focusing on electrification, driver assistance and infotainment Credentials North American Car, Truck and SUV of the Year (NACTOY) Awards Juror
9 min read
2017 Honda Clarity Fuel Cell
Antuan Goodwin/Roadshow

The new Honda Clarity Fuel Cell is both the successor to the FCX Clarity, which was produced in limited quantities between 2008 and 2014, and the first in a new series of Clarity vehicles that will span the gamut of modern green alternative fuels. We know that the tech inside the car works and does so reliably, but the future of the fuel that powers it is still uncertain. It's both a safe bet and a big risk, for both the automaker and the prospective buyer.

I spent a week with one of the very first, rare examples on the road in America to learn what it's like to daily drive, fill up and live with Honda's best bet for our automotive future.

The most common element, the rarest of fuels

Like that model that preceded it, this Clarity is a car that runs silently by converting hydrogen fuel into electricity to drive the wheels with the only tailpipe emission being pure water. You could actually drink this car's emissions -- it wouldn't taste like much, lacking the minerals of tap or bottled water, but it wouldn't harm you at all.

The hydrogen is stored in two high-pressure hydrogen tanks near the rear of the Clarity's oddly shaped body. A large tank is tucked in the trunk, just behind the back seats, and a smaller tank is nestled beneath that second-row bench. Total hydrogen capacity is just over 5 kilograms -- that's how the compressed gas is measured and metered -- which takes about 5 minutes to fill at the pump. The process of filling up is easy: swipe your credit card, lock the pump nozzle onto the Clarity's filling nipple and wait for the system to finish pumping chilled hydrogen into the tanks.

Hit the hydrogen-powered road in Honda's 2017 Clarity Fuel Cell

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Despite being the most common element in the universe, hydrogen has proven to be one of the rarest alternative fuel sources for cars. At time of publication, there are only 22 publicly accessible filling stations in the state of California. With the aid of services like the California Fuel Cell Partnership, I was able to see that only six of those are in the San Francisco Bay Area, but that number will double in early 2017.

Compare that to the hundreds of EV charging stations in the same area and it looks bleak for hydrogen drivers. However, that doesn't account for the fact that -- with charging times measured in minutes, rather than hours -- each of those hydrogen stations can services many more cars than an EV charging point. An occupied hydrogen pump means you'll have to wait a few minutes. Pulling up to an occupied EV charger usually means you've gotta find another charger.

During my week with the Clarity, I filled the tank twice. Upon delivery, approximately half a tank cost about $90. Near the end of my week, three-quarters of a tank cost me $68. The high cost and volatility of the price caused concern for nearly everyone I talked to about the Clarity. Both Honda and CAFCP hope that the price will drop by 25 to 50 percent by 2020 as the infrastructure continues to grow, but those are just estimates. For now, the Clarity's operations cost per mile are about in line with paying $5.60 per gallon of gasoline.

To relieve the sticker shock, Honda is essentially offering to pay for the Claritys' fuel with a $15,000 hydrogen allowance over a three-year lease term.

The improved hydrogen fuel cell

OK, so that's a lot of talk about how you get the fuel into the Clarity's tanks. Now what does it do with that fuel?

Well, without getting too science-y, the Clarity's fuel-cell stack combines hydrogen molecules with oxygen molecules pulled from the air to create water molecules. Electrons are released in the process making electricity that is used to power a 174-horsepower electric motor that moves the front wheels with 221 pound-feet of torque via a single-speed transmission.

2017 Honda Clarity Fuel Cell
Antuan Goodwin/Roadshow

The Clarity's powertrain also features a lithium ion battery pack that's about the same size and capacity as the Accord Hybrid's and is located beneath the front seats. The pack's purpose is to store and release electricity captured during regenerative braking and coasting, and to serve as a buffer for excess electricity generated by the hydrogen fuel cell when, for example, idling.

Below the stack, the system is largely identical to any other electric car with few moving parts and almost completely silent operation save a hum from the electric motor and the occasional whoosh from an electric turbocharger that force feeds oxygen to the fuel cell during hard acceleration.

The stack itself is 33 percent smaller when compared to the OG FCX Clarity, but with about 60 percent better power density. The new stack is so small that the whole fuel cell and electric motor package is now just a bit more compact than the automaker's gasoline 3.5-liter V6 engine, which you'll find beneath the hood of your average Accord.

Efficiency is stated in the neighborhood of 60-plus miles per kilogram of hydrogen fuel. Conveniently, the mile per H₂ kilogram measurement is numerically close to a gasoline mile per gallon equivalent (within an MPGe or two), making comparisons with electric, hybrid and conventional gasoline cars easier. I averaged 57.7 miles per kilogram during my weeks of testing, thanks to my being far too easily amused by electric torque and the novelty of hearing the electric turbo spin up when I accelerated a bit harder than absolutely necessary.

Eco car aerodynamics

Built with efficiency in mind, the Clarity features an aerodynamic humpback profile that is so typical of nearly all post-Prius eco cars. Drag coefficients haven't been stated by the automaker, but we're told that it's slippery, and we do know of a few features that help the Clarity cut through the air efficiently.

2017 Honda Clarity Fuel Cell
Antuan Goodwin/Roadshow

For example, at all four corners are small air intakes that force air through small openings ahead of each wheel, creating turbulence reducing air skirts at high speeds. Also, the fuel cell's lack of exhaust hardware or need for catalytic converters allows the sedan's undertray to be nearly flat reducing drag.

Despite its gently sloping profile, the Clarity is a sedan with a discrete trunk, not a hatchback. What's odd is that it has a small window just below the rear parcel shelf that allows the driver to look through the trunk and out of a second small window at the back of the car by glancing in the rear view mirror. It's an interesting novelty that I would guess is necessary so that Honda could boost the cargo capacity to compensate for space lost to the large hydrogen tank. Whatever the reason, this odd split view out of the back does help a bit with rear visibility.

Living with Clarity

Over the course of my week with the Clarity, I noticed a few quirks like how the fuel-cell powertrain continues to hum for many minutes after the car has been shut down, locked and walked away from. I'm not sure if the system was cooling itself or continuing to generate and store electricity while parked, but the behavior led to a number of confused queries from passengers and well-meaning passersby. "No, I didn't leave the car running. Yes, it's supposed to do that... I think."

On the road, the Clarity feels remarkably unremarkable, but that's probably because I've driven a lot of electric cars -- this is basically an EV with a different type of "battery" -- and also sort of the point. Acceleration for passes and merges is quite good, thanks to the torque-y electric motor and the sedan feels solid at city speeds. At highway speeds, the torque advantage is lessened, but the ride is remarkably quiet aside from a bit of wind noise.

2017 Honda Clarity Fuel Cell
Antuan Goodwin/Roadshow

Though it pulls from a stop like an EV, the fuel cell doesn't have that same low center of gravity that you'd get from an electric car with a heavy battery pack in the floor, but the trade-off is that the sedan doesn't feel as heavy as a battery EV and is a smooth and pleasurable drive at "dad speeds." Handling is about as good as an Accord or the old Accord Crosstour. The Clarity feels about as large as either of these, with similarly tuned steering feel.

There is a Sport mode toggle on the center console that boosts the throttle response and regenerative braking to simulate engine braking, but even with the boosts and instant-on torque this is no sports car. It's got some get-up-and-go, but on the whole, the Clarity feels tuned for efficiency, comfort and inoffensiveness.

Believe it or not, the "nothing fancy" nature of driving the Clarity is probably one of the strongest arguments in its favor, because while many of us enjoy a bit of novelty and gee-whiz in our drive, most are looking for familiarity from a commuter. The Clarity's range, filling behaviors and driving character are very much in line with gasoline cars. Those conventions will eventually make its adoption an easier green transition for the regular drivers that Honda is courting with this generation than EVs, which often require anxiety-generating changes in driving and refilling behaviors.

Good standard tech, not that you've a choice

Interestingly, the Clarity features only one trim level with all of the available features being standard. The only choice you'll have is what color you want, and even then you can only pick from white, black or red. The bright side of this lack of choice is that you get all of the tech without having to ask for it or pay extra.

That includes adaptive cruise control which also works at low speeds in stop-and-go traffic, lane departure alert and prevention and a standard head-up display (HUD) that projects speed and navigation information onto the windshield. You also get a standard rear camera, Honda's LaneWatch side camera and forward precollision alert with auto-braking intervention.

What you don't get is any sort of automatic parking, a true blind-spot monitoring system or any sort of parking proximity sensors or cross-traffic alerts, which would make great tech additions on a car this large with such a futuristic powertrain.

2017 Honda Clarity Fuel Cell
Antuan Goodwin/Roadshow

At 8 inches, the center HondaLink infotainment display is the largest that the automaker offers and looks more tablet-like than ever jutting away from the dashboard like it does here. The Android-powered software boasts the same very good Garmin maps and navigation software, solid feature set and snappy response to touch inputs that we've come to expect from the likes of the new Civic and HR-V.

And if you're not a fan of Honda's onboard software, Android Auto and Apple CarPlay are supported out of the box, so you can bring your own experience to the touchscreen.

Taking fuel cells mainstream

Exact pricing for the 2017 Honda Clarity Fuel Cell hasn't been announced, but educated guesses put the sedan at about $60,000 when it hits the road in the coming months. The Clarity feels like solid technology that's easy to live with, but is nonetheless waiting for the infrastructure to catch up with it.

Plans to double the number of hydrogen filling stations in California and to create a hydrogen network on the East Coast could pave the way for hydrogen going mainstream, but only if those plans -- which are dependent on state and federal government intervention to some extent -- reach completion. The Clarity Fuel Cell's modular design and compact powertrain pave the way for it to be joined next year by battery electric and gasoline plug-in hybrid variants, so it looks like even Honda is hedging its bets and not just letting it all ride on hydrogen's success.

2017 Honda Clarity Fuel Cell
Antuan Goodwin/Roadshow

If there's a station near you -- which means you live in one of California's major city centers -- fuel cell technology can be almost as convenient and normal feeling as its gasoline hybrid stablemates, but it's also a bit more expensive per mile for the short term future.

Hydrogen rivals

If you've gotten this far and still think that hydrogen fuel cell vehicles are for you, there's one more decision to face: Honda Clarity or the Clarity's fiercest competitor, Toyota's Mirai.

The Honda has the range advantage at 366 miles versus the Mirai's 312 miles, but with five-minute fill-ups that is less of an advantage for those who live near hydrogen filling stations. Meanwhile, the two vehicles have very similarly stated fuel efficiency estimates in the high 60 mile per kilogram range. The Honda also strikes with a size advantage. It's a much larger car with more room for people and cargo; plus, its seating configuration accommodates five butts versus the Toyota's four.

In the Mirai's favor, sometimes a smaller car is desirable, and the Toyota is expected to be less expensive than the Honda if the announced lease terms for both vehicles is any indicator.

I'd give the advantage to the Honda for now, but am reserving judgement until we get extended time behind the wheel of the Mirai. Based on these initial impressions and both automakers' offers of extensive three-year hydrogen fuel subsidies to ease transition to the alternative fuel, it's going to be a close call.

2017 Honda Clarity Fuel Cell
Antuan Goodwin/Roadshow