New Holland'sNH2 fuel cell tractor -
the first hydrogen-powered tractor to be shown by any tractor maker
- finally broke cover in Turin, Italy last Friday.
Based on a T6000 tractor, the prototype runs on hydrogen and
oxygen and produces nothing but water and will also be on show at
SIMA show in a couple of weeks time.
Essentially, a fuel cell works a bit like a giant battery, with
a pair of electrodes surrounded by an electricity-conducting
solution. Hydrogen (stored at 350bar pressure in a tank under the
bonnet) is passed over one electrode, while oxygen (from the air
pump) is passed over the other.
In New Holland's case, a catalyst on the surface of a membrane
extracts electrons from hydrogen gas.
This allows electrons to pass through an external circuit and
create electricity. Once on the other side of the membrane,
hydrogen recombines with electrons and oxygen to create water.
The electric current generated then passes to a pair of electric
motors, one to drive the rear and front axles and the other to run
the pto and auxiliary services.
The NH2's fuel cell generates 106hp and sends the power via a
splitter (from a
bi-directional TV6070 tractor) to the four wheels. There's no
gearbox or clutch and increasing speed simply involves generating
more power from the fuel-cell. Going into reverse is easy - you
simply flick the shuttle lever, which in turn reverses the fuel
cell terminals.
New Holland is the first to admit that there is still a lot of
development needed before this tractor will be on sale in dealers.
For a start, the hydrogen tank only holds enough fuel to power the
tractor for 1.5-2 hours, but this will be replaced by one which
will last up to 8 hours in prototypes to come, says NH. But
compared to how long a battery the same size as the hydrogen tank
would last (about 3 minutes'-worth of ploughing), producing power
on demand this way is viable.
What's the point of a fuel-cell tractor? No emissions and zero
reliance on fossil fuels are the main attractions. That may not be
that important now, but in 10 or 20 years they're likely to be
essential qualities for any vehicle.
Until now, hydrogen fuel cells have been prohibitively expensive
due to the platinum they contain. But fuel cells have already been
developed which use alternatives and the next step is to reduce the
platinum content in the rest of the cell.
The dream of a hydrogen-powered utopia has been thwarted by
boring practicalities. The lack of a national hydrogen distribution
system has prohibited automotive manufacturers from using this
technology. But, according to global marketing manager Pierre
Lahutte, this is where the tractor market differs.
Of course you still have to use electricity to electrolise water
into hydrogen and oxygen in the first place, but this is where New
Holland's energy-independent farm concept comes in.
The idea is that farmers will be able to produce their own
compressed hydrogen from water electrolysis and store it on farm
using with electricity generated via renewable sources, like
biogas, solar or wind.
Also, it's easier to stick a hydrogen tank under a tractor
bonnet rather than in a car - there's simply more space.
What's it like to drive?
Up in the passenger's seat the tractor seems a lot quicker than
a standard T6000, with a faster reaction when the foot throttle is
depressed. In fact engineers say that, on a straight track,
acceleration is enough to shove you to the back of your seat.
In the cab, the tractor is eerily silent. In fact the only sound
is the electric motor working, which is a bit like the noise a
large radio-controlled tractor makes. And when it's stationary
there is no noise at all, as it doesn't need to idle.
Essentially, losing the combustion engine and the usual gubbins
which goes with it means that reliability could be a lot greater as
there's less to go wrong. Not only this - but getting rid of what's
under the bonnet could lead to a redesign of the architecture of a
typical tractor.
The usual vertical exhaust pipe is gone, too - all you can see
is a small pipe under the cab that lets the water (the only
by-product of the fuel cell) out.
Instead of the standard rotating beacon, the cab is topped-off
by a strip of LEDs which "chases" round the edge of the roof. These
modifications could be added to ranges already in production,
before the launch of the fuel-cell tractors.
When and how much?
Not surprisingly, no price tags have been mooted and the
€300,000 cost of the fuel cell alone illustrates the fact that this
a tractor still some way from production. But the cost of the
prototype, at €500,000, is about the same as that of a normal
prototype.
The real question is to how expensive fuel cells will prove to
be in 2013. "All the technology is there and companies are already
using it. It's only the cost of the components that are
prohibitive," says Mr Lahutte.
But put these into mass production and cost could reduce
dramatically, he adds. "It all depends on how the automotive
industry adopts the technology."
New Holland reckons that a 130-140hp tractor would be the most
likely to use the technology, because it's the most commonly sold
and runs for more hours, meaning the return on investment would be
greater.
There's no real limit in terms of horsepower, though. "The
bottom line comes down to payback. It's just a case of stacking
cells to produce the amount required."
There's a second-generation prototype already waiting in the
lines, and expected on farm in 2010. New Holland says it plans to
have NH2 production models by 2013-15.