Believe It or Not!
An electric launch that runs on salt and water!
I wrote
a test report some while ago about a Duffy-Herreshoff 30 (“Picnic
Passage,” July 2002), a classic electric launch with an internal-combustion-type
generator/battery/electric-motor powerplant roughly analogous to those
found in today’s hybrid electric cars. The futuristic Herreshoff
made an impressive sea-trial showing. Among other things, her battery-charging
Northern Lights genset boosted her half-throttle operating range by almost
50 percent, from approximately 65 miles under electric power alone to
something like 95 miles in hybrid mode. Compelling stuff from the marine-technology
standpoint, for sure.
But
after the trial, something truly wild happened. I discovered during a
plant tour that the little company was stealthily working on a hydrogen
fuel-cell-powered version of the 30, perhaps with a tank of compressed
hydrogen as a fuel source—or maybe with something else, something
so radical no one would even talk about it.
The
source of the sodium borohydride that powered our fuel-cell test boat
was borax, a substance commonly found in both the Earth’s crust and
oceans. Presently, fossil fuel-powered manufacturing facilities create
sodium borohydride from raw borax in small batches for bleaching paper
in industrial papermaking operations—using the stuff to power fuel
cells is a radically new application. Hence, production is currently low,
and the price is high. Reportedly, the mixture of sodium borohydride and
water (see photo above) we filled our Herreshoff’s 45-gallon fuel
tank with cost approximately $50 per gallon—way more than we pay
for gasoline at the pumps these days. However, Millennium Cell and U.S.
Borax are working on clean, large-scale production methods they hope will
significantly lower the price of sodium borohydride and replace fossil-fuel
manufacturing methods with renewable energy resources like solar and hydropower.
I subsequently
tracked the project with a hound dog’s diligence, and recently the
folks at Duffy let me know they’d be introducing a fuel-cell-powered
Herreshoff at the World Maritime Technology Exposition in San Francisco.
The boat would transport attendees around the bay, thereby validating
Duffy’s developmental efforts as well as the efforts of other contributors.
These include Anuvu Fuel Cell Products, which had contributed an 8-hp
PEM (Proton Exchange Membrane) fuel-cell “stack” to the project;
Millennium Cell, which had contributed a Hydrogen-on-Demand system (the
“radical something” the folks at Duffy had refused to talk about);
and a host of other players and payers, including California State University
at Long Beach, the Department of Defense, the Department of Transportation,
and an outfit called Seaworthy Systems, noted for its expertise in marine
engineering, naval architecture, and overall marine project oversight.
A week
before the Herreshoff hit the road for San Francisco, I spent a day onboard,
examining the powerplant and exercising it on the waterways of Newport
Beach, California, Duffy’s homeport. Because I arrived extra early
at Duffy’s waterfront facility, I decided to find the test boat on
my own, there being nobody else around to guide me at the time. My plan
shortly began to falter, though. The fuel cell Duffy was darn near impossible
to locate because she looked so much like the 20 or so other Duffys on
hand. Finally, however, I stumbled across a Herreshoff with two little
differences: a clear Plexiglas engine hatch instead of a fiberglass one,
and a VHF-size, helm-mounted touchpad.
I peered
through the hatch like a sorcerer’s apprentice looking into a crystal
ball, examining an array of components that resembled the parts of a souped-up,
stainless steel air conditioning unit. I was scratching my head and mumbling
to myself when the three guys who’d been closest to the development
and construction of the boat arrived: Marshall Duffield, president of
Duffy Boats; Lyn Cowgill, R&D president for Anuvu Fuel Cell; and Mike
Strizki, senior lead scientist for Millennium Cell. We opened the hatch,
and Cowgill began telling me about “the next generation in marine
propulsion technology.”
Our
test boat was equipped with four 15-pound Anuvu Power-X fuel cells, each
capable of generating 1.5 kW, or the equivalent of 2 hp. They were assembled
side by side into a 60-pound, 8-hp fuel-cell stack and positioned against
the forward engine room bulkhead. Heavy-gauge wiring interconnected the
negative terminal of the stack, the positive terminal of the stack, a
20-hp electric motor in the bottom of the boat (linked to a three-blade
prop), a rheostat-type speed control (throttle), and an energy-stowage
bank of eight Trojan batteries—half the number found on the hybrid
version, which emphasizes batteries over internal combustion for power.
The
PEM (Proton Exchange Membrane) cells in our stack worked like others of
the type. Hydrogen gas entered on the anodic (negative) side, splitting
into two hydrogen ions and two electrons, thanks to a platinum catalyst
bonded to a special, semipermeable membrane. The ions moved through the
membrane and gathered on the cathodic side, creating a positive charge
there and leaving the negatively charged electrons behind. Voltage ensued
due to the charge difference across the membrane.
As soon
as Cowgill had finished with his exegesis, Millennium’s Strizki embarked
upon another, starting with the aspect of hydrogen fuel-cell technology
that’s drawn the most criticism over the years: hydrogen itself.
An invisible, explosive gas, it continues to evoke hard, practical questions,
not the least of them being how to compress and safely stow it, whether
in a car or onboard a boat. Moreover, while systems that reform or extract
hydrogen from gasoline or methanol—whether onboard or ashore—may
reduce emissions and fossil-fuel dependence to some extent, they eliminate
neither.
“But
this device,” Strizki told me, pointing first toward an enigmatic
apparatus atop the fuel-cell stack and then toward a plastic fuel tank
filled with a clear, watery liquid, “is altogether different. Instead
of reformed hydrogen, or compressed or cooled-liquid hydrogen in tanks,
it creates hydrogen on an as-needed basis using a simple mixture of salt
and water.”
“Salt
and water?” I responded in disbelief.
Strizki
hastened to explain that the salt the Millennium Hydrogen-on-Demand system
uses is not the common table variety but sodium borohydride, a white powder
manufactured from the common soap product borax (see “Salt?,”
this story). When combined with water in the presence of a proprietary
catalyst, it generates hydrogen on demand, together with some heat and
a recyclable borate residue.
Salt
and water, eh? Can you blame me for being just a tad enthusiastic about
cranking up the Herreshoff’s hydrogen fuel cell powerplant? I virtually
leapt onboard. Then came Cowgill, Strizki, and Duffield, who got behind
the wheel and gave the helm-mounted touchpad a couple of taps. In seconds
we were maneuvering away from the dock, although the process was not overtly
dramatic. The powerplant emitted nothing more than a faint, refrigerator-like
hum and a trickle of cooling water. “Darn near silent,” I commented
in amazement.
We sea-trialed
our Herreshoff for the next three hours. With an 8.6-mph top end, our
test vessel ran just shy of the 9-mph top speed I’d recorded for
the hybrid. Handling felt exactly the same, and so did throttle response.
Sound levels were generally lower than the hybrid’s, and operating
efficiencies were higher. Range at half-throttle (about 5 mph), for example,
was approximately 218 miles, while range at roughly the same speed for
the hybrid was only about 95 miles. And what’s more, there was no
smell and no smoke!
“Cool?”
inquired Duffield with an adventurous glint in his eye. The guy sees zero-emissions
fuel-cell technology carving a serious niche in the marine marketplace
over the next decade, first for gensets, then for high-horsepower, passenger-ferry-type
applications, then finally for recreational cruisers. And he sees his
little company surfing the big, fat, fun wave.
“Cool,”
I replied, darn near totally convinced that Duffield’s darn near
totally right.
Anuvu
Fuel Cell Products Phone: (916) 921-7040. www.anuvu.com.
Duffy
Boats Phone: (800) 645-1044. www.duffyboats.com.
Millennium
CellPhone: (732) 542-4000. www.millenniumcell.com.
This article originally appeared in the January 2004 issue of Power & Motoryacht magazine.
