Hydrogen Fuel Cell Ship Project On Track for 2008 Demo
03 August 2007
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| Cross-section of the Hot Module MCFC used in the FellowShip demonstration. Click to enlarge. |
The FellowSHIP (Fuel Cells for Low Emissions Ships) consortium, a group of Norwegian and German companies, is on track for the demonstration in 2008 of an offshore supply vessel powered by a 330kW molten carbonate fuel cell (MCFC).
The FellowSHIP project team consists of Det Norske Veritas (DNV), Eidesvik Offshore, MTU CFC Solutions (a wholly-owned subsidiary of Tognum), Vik-Sandvik and Wärtsilä Automation Norway. Phase I of the project, a feasibility study, ran from 2003-2005. Phase II, which began in 2005, will culminate next year with the demonstration.
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| Principle of the molten carbonate fuel cell. Click to enlarge. |
MTU CFC Solutions is providing a “Hot Module” fuel cell stack. In the Hot Module, incoming liquefied natural gas (the fuel gas in this case) is fed to the vertically-installed flow channels of the anodes via a gas distribution device. The horizontal fuel cell stack is sealed below through gravity. At a temperature of about 650 °C, the natural gas and steam split off the hydrogen needed on the anodes (internal reforming).
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| The full Hot Module system. Click to enlarge. |
The residual gas emitting from the upper part of the anodes is mixed with the additionally supplied air and afterwards catalytically oxidized. The gas mixture contains CO2 and O2 needed on the cathode. A fan circulates the gas mixtures through the horizontally installed flow channels of the cathodes.
The FellowSHIP technology will be up to 50 percent more efficient than today’s diesel power, while at the same time there will be no emissions of NOx, sulphur oxide (SOx) or particles. The CO2 emissions are reduced by 50 percent compared to diesel engines run on oil.
—Tomas Tronstad, DNV project coordinator
In August 2006, the US Office of Naval Research (ONR) awarded FuelCell Energy an additional $2.5 million to complete a land-based demonstration of its 0.5 MW ship service fuel cell (SSFC) power plant and begin design work on a next generation ship-based prototype.
The goal of that project is to improve the power generation efficiency on board ships—their non-propulsion hotel power—by adapting FuelCell Energy’s Direct FuelCell (DFC) power plants to run on naval liquid fuels (diesel and jet fuel).
Those liquid fuels need to be de-sulfurized before being used as fuel in the DFC plant. As a result, FuelCell Energy has developed a fuel processing system that removes the sulfur before reforming the liquids into methane gas, which can be used as a fuel in the power plant. (Earlier post.)
Resources:
FellowSHIP Fuel Cells for Low Emissions Ships project presentation (2004)
For ships, this may make a lot of sense. They can pull up to filling stations near LNG terminals, they have no need for fast transient response and, they can virtually eliminate vibrations in addition to harmful emissions. The latter is particularly useful in passenger applications. Also, the electric motors can be mounted on azipods that can swivel 360 degrees about a vertical axis, eliminating the need for a rudder and tow tugs in harbors.
On the downside, liquefying the methane will reduce well-to-screw efficiency. Also, LNG tanks must be vented at all times to avoid a dangerous build-up of pressure. That means such ships must be in use virtually all the time, possibly trickle-feeding an on-shore electricity grid while moored.
For smaller and occasionally used vessels, you'd need to switch to CNG or ANG (adsorbed NG). Weight would not be an issue, since you need some type of ballast anyhow. Plus, filling stations could simply tap into the regular on-shore NG distribution grid and deliver NG at near-atmospheric pressure. If required, the vessel would come equipped with its own compressor.
Posted by: Rafael Seidl | 03 August 2007 at 01:15 PM
They are going to need to get into the megawatts for be big cargo ships and crusie liners.
Posted by: Ben | 03 August 2007 at 03:38 PM
No cost data was mentioned in the article, but if this is cost-competitve with gas-fired turbine power plants, this would be great for distributed electrical generation with utilization of waste heat, thus raising efficiency from 60% to ~90%. PHEV owners would be delighted since they can recharge their car at night while using the waste heat to heat their home, using energy from natural gas already in place. The waste heat is also useful for absorptive cooler for summer time.
Posted by: Roger Pham | 03 August 2007 at 04:41 PM
This is the way to go for ship propulsion. Only one thing: where is the turbocompounder? Also, I would add a turboexpander to recover a lot of the liquifaction energy from the methane by heating it with seawater or air (whichever's warmer) and then waste heat. I would store the natural gas in liquid form in cylindrical tanks insulated by aerogel at a modest vacuum. Very little boiloff--and what boiloff there is will always have a use because there is always equipment running on a ship.
I show that the energy density of LNG is 21 MJ/l, or about 60% of that of diesel fuel. With the hot fuel cell and the above-mentioned efficiency boosts, you're looking at about the same tank volume versus diesel fuel and engine. You need to fit something around the cylindrical tanks to use up shape-constraint space. Perhaps backup diesel fuel. In any case, you're rarely hard-up for space on a ship for fuel. I would call the article's claims that this is a short-range vessel unthought-through.
You can store methane at even higher density if you want to compress to aggressive pressures like the hydrogen boys. This might be useful for taking advantage of stranded gas which cargo ships will be passing by on their routes, where liquefaction facilities don't exist because, say, the country doesn't have a good enough security or capital protection environment. (Use many small tanks for safety.)
Natural gas sources are distributed around the world, and ships will visit such sites often enough. It will be much better if ships move from oil to natural gas, because gas is not as concentrated in the middle east as oil is, and is a different kind of market, so the cartel power problem is weakened. Plus methane is a natural for making as a biofuel.
The powerplant will be more expensive, but not only will it pay back on fuel, it will help keep the peace in the world, and nothing is worse for the shipping industry than war. Clean air is icing on the cake.
Bring the first ones to the Port of Los Angeles, which is set to grow very fast but is pollution-limited, to tug dirty ships in and out the last few miles to shore.
Posted by: P Schager | 04 August 2007 at 07:45 AM
"liquefied natural gas" !!! Get real.
This is a pipe dream.
Posted by: DS | 04 August 2007 at 10:32 AM
CARB has just established somem hotel requirements for pollution control on Marins vessels visiting its harbors. Such a system appears a natural for such a requirement, if it is really practical.
Posted by: Stan Peterson | 04 August 2007 at 10:55 AM
A sensible use of fuel cells..avoids the inefficiencies of hydrogen PEM cells with the requirement to isolate and store H2. With biomethane approaches carbon neutrality.
Posted by: Michael | 04 August 2007 at 11:49 AM
DS -
what are you talking about, a whole fleet of LNG cryotankers have been supplying Japan's NG grid for decades. Collisions and terrorist attacks are concerns, but then that is true of oil tankers also. Other nations have since build LNG receiving terminals as well (US, UK, Germany, France, China, ...) Supplies come from a number of nations, including Brunei, Qatar, East Russia, North-West Australia, Algeria, Nigeria and others.
LNG tankers store NG at -163degC, because in liquid form it is 600 times more dense than at room temperature. NG is continously boiled off to control pressure in the tanks. This boil-off rather than diesel is used to power their engines, which are currently still regular ICEs.
http://www.shell.com/home/content/shellgasandpower-en/products_and_services/liquefied_natural_gas/dir_lng_300505.html
http://www.gazdefrance.com/EN/D/659/new-generation-lng-tankers.html
http://www.eia.doe.gov/oiaf/analysispaper/global/worldlng.html
Posted by: Rafael Seidl | 04 August 2007 at 02:05 PM
Regarding the safety and accident concerns, the solution is to divide the internal tank into enough cells with individual safety shut-off valves that still allow boiloff venting. Terrorists will go elsewhere, where they can get more bang for how hard they buck you. Small spills would be controllable and unlike oil spills, the gas is going to leave the scene vertically and disappear.
Put another way, LNG monotanks suffer from roughly the same conceptual problem as the Titanic--not enough cells. If terrorist think they can make us helpless a la Syriana they're wrong, they'd only force the issue and prod a redesign.
You'll lose your vacuum-optimized insulation layer more easily, but the resulting faster boiloff could be easily handled by an emergency burner vent. Chimney effect or blowers could disperse gas from small leaks before dangerous concentrations are reached. CO2 (with breathing gear) and foam would also help to keep any fires controllable.
Posted by: P Schager | 04 August 2007 at 04:44 PM
Rafael
what are you talking about!
I'm talking about cost. If the fuel were CNC it would be merely an overpriced fix. LNC make this a joke.
The simpler solution is "cold-ironing" or a T2B5 diesel.
Posted by: DS | 04 August 2007 at 08:59 PM
DS -
we may be at cross purposes here. LNG is definitely not cost-effective for many types of vessels, e.g. container ships. Smaller vessels would almost certainly use CNG or ANG instead.
However, for selected applications, in which e.g. minimal vibrations are a competitive advantage, an LNG-powered fuel cell could be interesting.
T2B5 applies to on-road LDVs. The high sulfur content of bunker oil would very quickly poison or destroy the catalysts in such a system. Removing the sulfur from heavy fuel grades is much more difficult than doing so for the lighter grades.
Posted by: Rafael Seidl | 05 August 2007 at 03:32 AM
"The FellowSHIP technology will be up to 50 percent more efficient than today’s diesel power"
I can't believe that claim at all. Ship diesel engines are already at over 50% thermal efficiency. If they are claiming 50% improvement on that, then they are claiming a 75% efficient fuel cell!!
Posted by: clett | 06 August 2007 at 04:38 AM
Clett -
75% is high but theoretically quite possible in a narrow operating range. Marine diesels don't get 50+% over their entire engine map, either.
Posted by: Rafael Seidl | 06 August 2007 at 04:11 PM
I contend that 75% is not unrealistic at that scale if you use a bottoming cycle.
MC Fuel cells are quoted as up to 60% efficient and run at 650C or 923K. That should give you an effluent that can produce power at a Carnot ceiling of 68%. If you made a Stirling that achieved half that (conservative for a big Stirling), that's 34% of the remaining 40% of the original energy or an additional 14 points on top of the original 60% from the fuel, or net 74%. (I didn't count energy recovery from cryogenic LNG.)
Or to quote from http://www.ctfuelcell.uconn.edu/cgfcc_faq_fc.htm ,
"Power generating efficiencies for molten carbonate fuel cells is 55% and can be increased to about 75% by the addition of a gas turbine bottoming cycle using the waste heat."
Posted by: P Schager | 07 August 2007 at 12:14 AM
@ P Schager -
there aren't many really big Stirling engines on the market, so perhaps a gas turbine for he bottoming cycle would be more realistic.
Btw, the lower heating value of natural gas is roughly 25MJ/kg, of which 75% (= 18.75 MJ/kg) would be converted into electricity and/or shaft power.
By contrast, the purely physical cold energy stored in LNG relative to sea water at 0 degC is 0.89 MJ/kg. The Carnot limit for a process operating between 0 degC and -160degC is roughly 60%, so figure 40% (0.36 MJ/kg) tops for a real-world Stirling engine. That's just 2% of what the fuel cell-as turbine combo yields and therefore, probably not worth it.
Note that it takes some multiple of 0.89 MJ/kg to actually refrigerate NG below its boiling point to begin with. This needs to be considered in any well-to-screw comparison against conventional diesel propulsion.
Posted by: Rafael Seidl | 07 August 2007 at 10:04 AM
Hi, I' ve gotta a question for you. What do you use for a cooling system for a Hydrogen fuel cell power source too produce energy on a vessel? Is it sea-water?
Posted by: Paul | 21 October 2008 at 10:42 PM