| FuelCell
Works News -Supplemental
May
15th 2002
"Mommy,
are we there yet?"
Source:PEI
The announcement that
the world's first fuel cell-gas turbine hybrid system had passed a key
site
acceptance test made
interesting reading. US Energy Secretary Spencer Abraham commented: "This
new technology has
the potential to alter the landscape of tomorrow's power industry." Well
it will - a bit. And not just yet.
The joint announcement
at the end of March by Abraham, Siemens Westinghouse Corp. and Southern
California Edison
outlined that a 200 kW system had passed the 1000 hour proof-of-concept
period.
The system installed
at the National Fuel Cell Research Centre on the Campus of the University
of
California-Irvine,
is owned by Southern California Edison. It uses a solid oxide fuel cell
in 'combined
cycle' mode with an
Ingersoll Rand microturbine, whereby the hot pressurized exhaust from the
fuel
cell is used to drive
the microturbine.
In addition to such
systems 'changing the landscape of the power industry', Abraham also said
that
they could "make distributed
generation a reality" and added "... it could play a key role in strengthening
the security and reliability
of our power supply." And this is where the future role of such systems
lies.
Predominantly due to
costs, distributed generation (DG) is unlikely to ever replace larger centralized
power but there is
a market for DG products. Allan Casanova, director of business development
of
Siemens Westinghouse's
stationary fuel cell division, said: "In 2005, when considering all fuel
cells,
the market is in the
region of 1 GW - the US represents 50-60 per cent of this. We see these
systems
as complementary to
central station power - for grid support, power quality and on site power
applications... but
we need to have a value proposition which allows the customer to generate
electricity in the 5-10 cents/kWh range from systems of 5-20 MW."
Siemens Westinghouse
realises that the efficiency and outputs of hybrid systems must move to
higher
ratings. With the
volatility and recent highs of gas prices around the world, improved efficiency
is
especially important
to making the system economics work for t he end user.
Currently, two more
slightly larger proof-of-concept systems are being built in Europe - for
RWE in
Germany, and Edison
SpA in Milan, Italy. These are 300 kW systems which have some changes in
subsystems compared
to the California installation. They are expected to achieve higher efficiencies
than the 53 per cent
of the Californian system. The RWE system will start up in late summer,
while the
system in Italy will
be in operation "later this year". The plan is to run the systems for one
year, with
system tests occurring
in late 2003/04.
Casanova noted: "We
also plan a 550 kW pressurized hybrid system and we are looking at these
300
kW and 500 kW systems
as base product, proof-of-concept systems. The key challenge to having
a
high efficiency hybrid
is a definite purpose microturbine or small gas turbine that gives us a
better
match with the air
flows from the fuel cell and the outlet and inlet temperatures of the turbine
we are
interfacing with.
When we go to multi-megawatt systems we can get a much better match from
gas
turbines that are
more readily available."
Pressurized hybrid
systems will not be commercially available until around 2005. Scale up
to
multi-megawatt systems
will then take place over the next couple of years after this. "We need
to
have these bigger
systems with efficiencies of 58-70 per cent since this is the size at which
we
could give the distribution
utilities the opportunity to provide grid support at the substation level,"
said
Casanova.
Commercial fuel cells,
and systems incorporating their use, have been a long time coming and there
is
still a lot of work
to be done. Siemens Westinghouse is focussing on the commercial launch
of a 250
kW, atmospheric CHP
system before scaling up to the pressurized hybrid. Randy Zwirn, president
and
CEO of Siemens Westinghouse
Corp. noted: "Now, after 20 years of researching and developing fuel
cell technology and
implementing projects like the Irvine system, we plan to deploy our first
fuel cell
products in the commercial
market by the fall of 2003."
Certainly, I have
been writing about fuel cells and hybrid fuel cell systems with 70 per
cent
efficiencies for at
least ten years and will probably be writing about them periodically for
some time to
come. "So how long
before we get there?" The best we can offer is: "Soon darling."
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