generate the highest emissions per
passenger kilometre, which implies
a great potential for fuel cells in the
marine industry,” he says.
The US Naval Research Laboratory is
experimenting with turning seawater into
fuel by desalinating it and splitting H2O
into hydrogen gas, which is captured, and
oxygen, which is vented. The only current
problem is that the power needed to make
enough hydrogen to power a warship is
about equal to the energy output of
a nuclear aircraft carrier. The technology,
if scalable, is promising. In the meantime,
hydrogen could be used to support
auxiliary operations and longer periods
of silent running.
Energy Observerjust celebrated its first
anniversary of green power by beginning
its 2018 Mediterranean tour. This 30.5
metre catamaran was developed for
a six-year circumnavigation using only
renewable energy and hydrogen gas. Its
electric propulsion motors are powered
by solar cells and wind turbines during
the day and by fuel cells charging its
battery banks at night. It will use
electrolysis to charge its hydrogen fuel
cells. The entire power generating system
weighs 2,100kg. New, lighter batteries will
be installed in 2019.
Sandia National Laboratories says it
has an advanced concept for a zero-
emissions, 35-knot, 150-passenger,
electric ferry for San Francisco Bay
powered by hydrogen fuel cells. The
development was funded by the US
Department of Transportation’s
Maritime Administration and led by
Sandia, a division of Lockheed Martin.
The hydrogen ferry would cost about
twice as much as a comparable diesel
ferry at today’s prices. Much of that cost
is in the fuel cell system.
“Right now, we can’t achieve economic
parity with a comparable diesel ferry,”
says Sandia researcher Joe Pratt, “but this
is a question we need to explore further.
Is economic parity necessary from the
outset? Lessons from the automotive
market tell us maybe not.” In fact, a fleet
of hydrogen-powered taxis called Hype
Taxis has been operating in Paris since- The fleet of cars, now up to 75, have
a range of 500 miles and can refuel in
three to five minutes, unlike electric cars
which take hours to recharge. The savings
in time to refuel versus time to recharge
are proving popular.
THE STATUS OF
STORAGE BATTERIESF
or years we have been hearing
that the only major impediment
in the development of green,
electric-powered yachts is the lack of
advanced storage batteries. Although the
average lithium-ion battery is four times
as energy dense as lead acid and has
a greater life cycle expectancy, especially
in hot climates, even the latest lithium-
ion batteries ofer only about 10 per cent
of the energy of diesel fuel – not “power-
dense” enough to run a superyacht and its
house loads for more than a few hours in
the best conditions. Newer batteries – the
phrase is “post-lithium-ion” – appear to
be moving to lithium-air or lithium-metal
for higher energy density, in some cases
twice as much.
Battery technology is subject to an
enormous amount of research and
development as a result of demand from
the automotive, power distribution and
electrical goods industries, notes BMT
Nigel Gee. “It is likely that battery“It’s possible that
a transformational
battery may be
developed and
brought to market”
Right: Grace E, now
Nautilus, the 73m
Perini Navi/ Vitruvius,
has a diesel-electric
power plant and Azipod
propulsion. The power
plant was supplied by
ABB, which works with
the cruise ship industry
and, increasingly, with
large yachts tooA MOVABLE BEAST
Hybrid propulsion 2.0Pod drives removed the design restrictions imposed by having to allow a propeller shaft run, but Wider
Yachts was the first to abandon the traditional engine room by splitting propulsion and power generation,
thus returning real estate to accommodation and breaking up power generation into smaller units.http://www.boatinternational.com | June 2018PHOTOGRAPHY: GIULIANO SARGENTINI; THIERRY DEPAGNE196