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The fuel cell:A technical report.
Energy moving into the future
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Managing global energy supplies is increasingly becoming a
key issue for the future of mankind. If present usage levels are
sustained, fossil energy resources created over several hundred
millions of years will be used up within just a few generations.
The future of energy supply lies in opening up renewable energy
sources and developing new technologies such as the fuel cell.
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The fuel cells potentialFor decades, the internal-combustion engine has been a hallmark in the history of the automotive industry and of stand-alone energy supply. To most users, it hasso far been the only appropriate solution to drive cars or generate power at remote sites. Fuel cells offer, for thefirst time, the chance to replace the combustion enginein a number of applications and thereby avoid harmfulemissions.
For the energy industry, they open up the option ofsustainable, resource-saving supply, and thanks totheir ecological soundness many diverse applications.This includes applications in the mobile sector and allareas of the energy industry.
The fuel cell looks back on a long track record. As early as 1839, an Englishman, Sir William Robert Grove(1811 1896), constructed the first fuel cell. Its furtherdevelopment proved such an arduous task that Grovesconcept was only used in isolated applications for nearly100 years. His fuel cells featured electrodes made of platinum sitting in a glass tube with their lower endimmersed in dilute sulfuric acid as an electrolyte andtheir upper part exposed to hydrogen and oxygen insidethe tube. This was sufficient to produce a voltage of 1 volt. To turn the fuel cell into a really efficient sourceof power, substantial technical efforts had to be made.
Over 160 years have lapsed since the fuel cell was in-vented. Its true potential as the energy converter of thefuture has only recently manifested itself. Today, it is onthe point of commercial use.
Sir William Grove
(1811 1896) constructed
the first fuel cell
Groves historic fuel cell (1839)
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New prospectscreated by an old idea.
Fuel cells can revolutionize the energy sector
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Fuel cells generate electricity from hydrogen and oxygen without any harmful
emissions and therefore in an extremely environmentally friendly way. Heat is
produced in varying amounts and, as a by-product, water.
The fuel cellprinciple.
A powerful concept for resource-saving harnessing of energy
Operating principle of the fuel cellA proton exchange membrane iscoated with a thin platinum cata-lyzer layer and a gas-permeableelectrode made of graphite paper.Hydrogen fed to the anode side ionizes into protons and electrons
at the catalyzer. The protons pass thecatalyzer layer, while the electronsremaining behind give a negativecharge to the hydrogen-side elec-trode. During the proton migration,a voltage difference builds up be-tween the electrodes. When theseare connected, this difference pro-duces a direct current that can drivean engine, for example. Finally, theprotons recombine with the elec-trons and the oxygen into water atthe cathode.
Besides the recovered electricenergy, the only reaction product iswater. Additionally, heat is producedby the electrochemical reactions andthe contact resistances in the fuelcell, which can be used for space orservice water heating.
The voltage of a single non-oper-ated cell is about 1.23 V (volts). Inoperation, this level falls to about0.6 to 0.7 V under load. As this level
is too low for practical applications,a sufficient number of cells is con-nected in series to obtain a usablevoltage. They may add up to 800cells in larger-sized plants.
The line-up of cells is equivalentto a stack, and this word has becomea technical term generally used forthis arrangement.
It is characteristic of fuel cells thatthey generate a DC voltage. To allowpractical use, it has to be transformedinto an AC signal. This is done bydownstream DC/AC converters.
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Hydrogen Oxygen
Excessoxygen
Excesshydrogen
Electrolyte
Reaction water
CathodeAnode
Electricalload
How a fuel cell works
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Benefits of fuel cellsFuel cells convert hydrogen and oxygen intoelectric energy. At the same time, heat is pro-duced that lends itself to supplying processheat, producing hot water and delivering heatto buildings. If operated as co-generation units(combined heat and power generation CHP),fuel cells reach energy conversion rates of up to 80 percent and can therefore make a sus-tainable contribution to energy saving.
Compared with conventional techniques, the use of fuel cells holds additional promise.This includes high efficiencies even whereplant capacity is small, constant efficiencyunder part load, simple and modular design,low maintenance expenses and a level of hazardous substance emissions so low that itcannot be achieved with any other technique.
As hydrogen is directly converted by electro-chemical reactions, the efficiency of fuel cells is
unlike traditional energy conversion processes not limited. Fuel cells can therefore reach muchhigher efficiencies than internal-combustionengines.
Fuel cells are also effective under part load.Unlike in conventional systems, the efficiencyremains largely constant until 50 percent fullload. This has merits for plants which are fre-quently operated under part load (e.g. motorvehicles in inner-city traffic).
Carbon dioxide emissions (CO2) result fromuse of carbonaceous fuels. These include all fossil energies such as coal, oil and natural gas.As fuel cells will in the medium and long termuse fossil resources (natural gas) as an auxiliaryfuel, their use also leads to carbon dioxide emissions. But thanks to combined heat andpower generation and the high efficiencies, CO2 emissions will be lower than in conven-tional systems.
50 percent part load
Coal-fired plant
Efficiency
Gas turbine
Fuel cell
Full load
Practically
Theoretically
NOx CO CHx
BHPP FC
50
100
150
200
0
250
300
350
mg/Nm3 (mg / standard cubic meter) Source: HEW
Comparison of emissions
Compared with established technologies block heat and
power plants (BHPP) or other power plants fuel cells (FC)
boast very low emission levels.
Part-load efficiencies of fuel cells
The operating parameters of fuel
cells look favorable even under part
load. As opposed to conventional
plants, efficiency remains constant.
This qualifies fuel cells for use in
units frequently run on part load
(e.g. vehicles in inner-city traffic).
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Five fuel cell technologies are at present being developed.They differ in
their electrolyte structure, working temperature and fuel requirements.
Their designations refer to the electrolyte used.
The fuel cell technique is on the point of commercial use in many areas
Fuel cell types and applications.
Type Electrolyte Special features Applications
SOFC Solid Oxide Solid zirconia Direct power production Central and stand-aloneFuel Cell from natural gas, ceramics CHP generation
MCFC Molton Carbonate Molten Complex process control, Central and stand-aloneFuel Cell carbonates corrosion problems CHP generation
AFC Alkaline Fuel Cell Aqueous High efficiency, Space operations,potash lye pure H2 and O2 only defense
PAFC Phosphoric Acid Phosphoric acid Limited efficiency, Stand-alone CHPFuel Cell corrosion problems generation
PEMFC Proton Exchange Proton exchange High flexibility in operation, Vehicles, stand-alone Membrane Fuel Cell polymer high power density CHP generation
membrane (small-scale)
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Solid Oxide Fuel Cell (SOFC)Solid oxide fuel cells are designed for usein all areas of electricity supply. At workingtemperatures up to 1000 C, they havepotential for highly efficient energy sup-ply. In particular if combined with mod-erately priced gas turbines, SOFC cellscan in future also be used to constructsmall-scale generation plants with effi-ciencies comparable to those of naturalgas fired combined-cycle power plants.Mini-plants for residential and small com-mercial applications are being developedby Swiss Sulzer Hexis AG, and larger-sizedplants with capacities between 250 kW(kilowatts) and 20 MW (megawatts) bySiemens Westinghouse.
SOFC fuel cell with gas turbine
Replacing the gas turbine combustion chamber
by a fuel cell leads to a hybrid process, raising the
gas turbines efficiency from less than 30 percent
to over 60 percent.
Fuel cell
Natural gasWaste heatexchanger
Compressor
Generator
Turbine
0.1 1 10
10
20
30
40
0
50
60
70
80
0.01 100 300 1,000
Gas turbineGas engine
PEFC PAFC
SOFC, MCFC
SOFC-, MCFC-Combined-cycle power plant
Combined-cycle power plant
Future: upper valuesPresent: lower values
Electric power output in MW
Electrical efficiency in percent
Fuel cell efficiency
The efficiency of fuel cells is not limited by the Carnot process as hydrogen
is directly converted by electrochemical reactions. Fuel cells can therefore
attain considerably higher efficiencies than comparable internal-combustion
engines.
Fuel cell types
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N2, unconverted O2and reaction gas
Load
O2
CathodeAnode
Electrolyte
Fuel gas
Unconverted fuel gasand reaction gas
900 1,000 C
600 650 C
160 220 C20 120 C
60 120 CAFC
OH
PEMFC
H+
MCFC
CO32
O2
SOFC
PAFC
H+
O2
O2
CO2
O2
H2O
O2
H2O
H2
H2O
H2
H2
CO2
H2O
COH2
CO2
H2O
COH2
160 220 C20 120 C
N2, unconverted O2and reaction gas
Molten Carbonate Fuel Cell (MCFC)Molten carbonate fuel cells working attemperatures between 500 C and 600 Care being developed for industrial appli-cations. They permit electricity genera-tion with high efficiencies (approx. 55percent) and simultaneous production of process steam, offering excellentpotential for industrial combined heatand power generation. In Germany, aprominent developer of this technology is MTU, and in America, Fuel Cell Energy is foremost.
Alkaline Fuel Cell (AFC)Alkaline fuel cells are distinguished by a combination of low working temper-atures and high efficiencies. They arefavored for niche applications in thespace industry or the maritime sector, e. g. to drive submarines. The demandsthis cell type makes on the purity ofhydrogen and oxygen clearly limit thepractical scope of use. This fuel cell typeis developed by ZeVco (Zero EmissionVehicle Corporation) and others in Germany; worldwide, IFC (InternationalFuel Cell) and Fuji work on it.
Phosphoric Acid Fuel Cell (PAFC)Opportunities for phosphoric acid fuelcells working at temperatures around 200 C are in combined heat and powerproduction. Administrative buildings,hospitals, indoor pools but also large resi-dential estates are potential applications.Over 180 plants supplied by Americanmanufacturers ONSI are operated world-wide and have in part already beendecommissioned after reaching theirexpected service life. They are proof of the vast interest in using the fuel celltechnology. Still, experience with thistechnique has given rise to some doubtsabout its further success. They concernthe limited potential for saving manu-facturing costs, and technical restrictionsresulting from the need to constantlymaintain temperatures. Besides ONSI,Japanese companies Fuji and Toshibawork on this method.
Proton Exchange Membrane Fuel Cell(PEMFC)Employing fuel cells in the end user mar-ket is seen as a particularly interestingopportunity. About 25 percent of primaryenergy consumption in Germany areaccounted for by space heating and hotwater supply, so that use of fuel cells asCHP plants would contribute to energysaving. That temperature levels are rela-tively low in the supply of hot water forspace and service water heating opens up a range of applications for low-temperature cells with proton exchangemembranes.
PEM fuel cells are used in the Berlindemonstration project. With an electricpower output of 250 kWel , this is their firstcommercial-scale application in Europe.The success of this project will be animportant prerequisite for marketingplanned from 2004 onwards.
Energy consumed in Germany to supply heat
About 25 percent of the primary energy con-
sumption of 492 x 106 tons of hard-coal equiva-
lent were used in 1998 to meet space heating
and hot water needs.
Chemical reactions in each fuel cell type
9 %
34 %
57 %
Processheat
Hotwater
Spaceheating
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89
Water vapor
Shift converter Fuel cell
Shift reactionReformer reaction Total
Product water
Water vapor
Anode off-gas (H2)
Making hydrogen availableIndustrial sources are, for example, che-mical industry operations. The excessH2 produced in synthesis gas manufac-ture has already found its way into theenergy supply sector, and can in futurebe used more widely. The same appliesto electric energy that is freely avail-
able in low-load periods. Electrolyzeroutfits can be employed to producehydrogen out of it and use it in peakload periods to cover electricity needsor supply vehicles with H2.
Recovering hydrogen from renewableenergies is today still seen as a futureoption. Economic reasons will continue
to reduce it to niche applications forsome time. Fossil energy sources suchas natural gas and mineral oil appearto be the most promising sources forhydrogen production in the mediumterm. This requires treatment so-called reformation processes to beinstalled upstream of the fuel cell.
Natural gas reformation
The futures nameis hydrogen.
Hydrogen stores renewable energies
Hydrogen is not freely available in nature. Chemical and
electrochemical processes will therefore long have to be used
to recover it.
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Fuel cell
H2storage
Electrolyzer outfit Electrolyzer outfit Reformer
Renewable energy Excess electricity Industrial sources Natural gas reformation
Hydrogen production through reformationReformation is a multi-stage process trans-forming hydrogen-containing energysources into hydrogen-rich gases. As thisprocess consumes energy, it results indrawbacks to the energetic overall effi-ciency of a fuel cell process.
In a first step, natural gas is split in areformation reaction into a gas mix con-sisting of three parts hydrogen (H2) andone part carbon monoxide (CO). In addi-tion to process heat (+205.8 kJ/mol, i. e.kilojoules per mol), this requires feedingof water vapor as a coreactant. In a sec-ond step, the remaining CO is, with thehelp of steam, oxidized to carbon dioxide(CO2) in a shift reaction. It releases a fur-ther free hydrogen molecule. The finalproduct is a gas mix consisting of fourparts H2 and one part CO2 which can bedirectly used in the fuel cell.
The shift reaction is exothermic, i.e.connected with a release of energy ( 42.3 kJ/mol). This energy can be employedto partly cover the energy demand of refor-mation. PEM fuel cells are normally highlysensitive to CO contained in the fuel gas.Carbon monoxide is regarded as a catalyzerpoison. These fuel cells therefore necessi-
tate removing residual CO in a third oreven fourth treatment stage, which isdone in a process called selective oxi-dation.
The entire gas treatment process in-volves a 20 to 30 percent loss of energy,which detracts from the efficiency of thefuel cell process. Losses are lower whenhigh-temperature fuel cells are used.They permit internal reformation of thefuel inside the fuel cell, which leads tohardware savings and efficiency advan-tages. But the price paid for these bene-fits is that expensive materials with high temperature resistance have to be used.
State of the artFuel cells have reached a maturity todaythat allows building complete plants incommercially usable sizes. They serve asdemonstration units for their manufac-turers to test and optimize their plantconfigurations, and help their operators mainly energy utilities gain initial ex-perience with this new technology. Thisis also the purpose of the Berlin fuel cellproject. Demonstration projects shouldnot be confused with commercial fuel cellapplications. This needs further years ofdevelopment and operating experience.With a view to mobile applications, thismeans in particular that a decision has to be made which energy resource will infuture be needed either hydrogen isdirectly used, or methanol serves as anintermediate solution. For stationaryapplications, efficient and compactreformers will have to be developed thatallow low-cost conversion of natural gasinto hydrogen-rich gas.
Many companies have committed toworking intensively on development.Even well-renowned manufacturers nev-ertheless assume that both mobile andstationary serial products will not becommercially available until after 2004.
Methods of
hydrogen recovery
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Design of a PEM fuel cell
A fluorine-containing polymer
membrane is the outstanding
feature of the PEM fuel cell design.
Vaporized with a catalytic precious
metal and covered by a gas-
permeable graphite electrode, it is
enclosed by two bipolar plates.
PEM fuel cells boast simple design
and uncomplicated manufacture.
1 Flow field plate (fuel supply)
2 Hydrogen supply3 Membrane electrode
assembly4 Air supply5 One fuel cell
pulled apart6 Stack consisting of
several cells
6
1 3
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Simple and low-costA fluorine-containing foil, vaporized with a catalyticprecious metal and coated with a gas-permeableelectrode made of graphite paper, is enclosed by twobipolar plates made of metal or graphite. Groovesmilled or pressed into the plates allow feeding ofhydrogen and oxygen or air to the anode and cathode.The simple design of the PEM fuel cell suggests thatmanufacture will in future be low-cost, permittingmass production as usual e. g. in the automotiveindustry.
Merits of PEM fuel cellsPEM fuel cells outperform competing technologiesin a number of ways that speak in favor of their goodmarketing potential. The following aspects are coreto its superiority:
PEM fuel cells are appropriate for mobile and sta-tionary use.Their versatility in application suggestssynergies, with cost benefits lying with stationaryapplications.
PEM fuel cells have the highest power density com-pared with competing technologies, with potentialfor further development.This allows building small,space-saving systems as required for remote-siteapplications.
PEM fuel cell applications in power supply rangefrom mini-systems generating a few watts via stand-alone units in combined heat and power to applica-tions in stand-by power supply a universally usabletechnology.
Description of the PEM fuel cell.
A variety of applications
200
400
600
800
0
1,000
1,200
Watts / liter
1995 1997199319911989
Development of
the power density
of PEM fuel cells
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Project venture and project costsFive energy utilities participate in the Berlin fuel cell project: Bewag as the projectleader, lectricit de France (EdF) Paris,Hamburgische Electricittswerke AG (HEW) Hamburg, Hanover-based PreussenElektraAktiengesellschaft (now E.ON Energie AG,Munich) and Vereinigte Energiewerke Aktien-gesellschaft (VEAG) Berlin. Canadian manu-facturers Ballard Generation System (BGS)supplied the plant, and ALSTOM deliveredthe complete system.
ALSTOM regards the Berlin project as animportant step towards commercial-scaleintroduction of fuel cells. The company has plans for the future to jointly producecomparable plants in series with its partner Ballard in a new Europe-based company.They will hinge on successful completion of the Berlin demonstration project.
Project costs amount to an approximate 3.8 million. The innovative character of the project and its expected favorable impacton the European economy persuaded theEuropean Commission to financially assistthis project. It contributes 40 percent of theproject costs. The remainder is taken byALSTOM (around 10 percent) and the powersuppliers in charge (around 50 percent).
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The Berlin 250 kW PEM demonstration project.
The Berlin fuel cell project managed by Bewag is the first of its kind in
Europe.The project is the first to employ the PEM technology in the
200kW class in Europe.Three further plants are being installed as part of
a field test one plant in Switzerland was commissioned in fall 2000,
another plant in Belgium in spring 2001, and a fourth unit will take up
operation in the Netherlands in the second half of 2001.
A proud European cooperation venture
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Project descriptionNatural-gas based PEM fuel cells consistof three partial systems: Gas treatment toconvert natural gas into hydrogen, the fuelcell stack, and the downstream AC/DCconverter generating an AC voltage.
The system applied in Berlin follows thisbasic design. If compared with competingsystems, however, it differs not only in thefuel cell type. The complete fuel cell systemincluding the upstream gas treatment unitworks under pressure. The four bar opera-ting pressure allows compact plant designwith reduced volumes of building materials.For the stack, this means a boost in powerand efficiency compared with atmosphericoperation.
After entering the plant, the natural gasis stripped of sulfur, reformed, and thenstripped of carbon monoxide (CO) by wayof oxidation to carbon dioxide (CO2) in theshift reactor and the following conversionstages. Subsequently, the gas mix fourparts hydrogen (H2) and one part carbondioxide (CO2) is fed to the fuel cell. AnyH2 not utilized in the fuel cell serves toheat the reformer. The steam additionallyneeded for reformation comes from con-densate recovered from the off-gas of thefuel cell. Under part load, demineralizedwater from the neighboring heat plant is used to balance any potential watershortage.
Pressurized operation requires compres-sion of natural gas and process air neededin the fuel cell. It is particularly the energyrequired to compress the air that triggersa distinct increase in station service needs.Utilizing the energy contained in the off-
gas with a turbo-supercharger helps to largely avoid this additional station servicerequirement.
The process design provides for outputof heat for heating purposes. Cooling waterruns through the cell in a primary coolingcycle which transfers its energy via a heatexchanger to the connected district heat-ing network. In the absence of any heatload, a stand-by cooler is used to ensuresufficient re-cooling of the primary coolingcycle.
An AC/DC converter sits downstream ofthe fuel cell. It transforms the DC outputsignal of the fuel cell into an AC voltagesignal utilizable for mains feeding.
The plant has a package design, with thecontainer housing all modules needed forthe process: gas treatment, fuel cell andinverter. Operation additionally requiresthe natural gas service connection, thehook-up to the district heating system, thepiping for process gases such as nitrogenand compressed air, and the demineralizedwater supply.
The fuel cell plant functions as an integralpart of the existing Berlin-Treptow heatplant of Bewag. This heat plant with itstwo 12.7MW steam boilers and an 18.7MWhot water boiler supplies to a local heatingsystem with a maximum demand of 25 MW.Minimum demand in summer is 500 kW.A bypass allows to connect the fuel cellwith the existing district heating system. A heat exchanger is used for heat removalto the return flow. Part of the return flow isthis way heated by about 10 K, usuallyfrom 65 to 75 C. The temperature level ofthe return flow that is low throughout theyear is, in connection with the high heatdemand, the prerequisite for fully reclaim-ing the heat rejected by the fuel cell.
The fuel cell is dimensioned for an elec-tric power output up to 250 kW. This is sufficient to cover the entire electricityneeds of the heat plant. The demand isoccasioned by the pumps recirculating the heating water, the driving gear of theburner ventilators and other loads neces-sary to ensure operation of the heat plant.
Air
Off-gas
Naturalgas
Anode/cathode off-gas
Reaction water
Air cooler
Start-up air
4 H2 + CO2
250 kWel
400 V 3~
Return flow districtheating network 230 kWth
H2 from electrolyzer outfit
Make-up water
Fuel cellReformer ShiftconverterCO
converter
Gas treatment
Turbo-supercharger
Process of the 250 kW PEM fuel cell plant
Besides use of the PEM fuel cell, the typical feature
of the plant is that the process is pressurized.
It allows compact design but requires increased
maintenance input.
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Flow85 C
Return flow75 C
65 C
75 C
Flow: max 70 CAverage temperature: 58 C
Steamboiler
12.7 MWth
Steamboiler
12.7 MWth
Hot-waterboiler
18.7 MWth
Fuelcell
230 kWth
Maxheat
demand25 MWth
Return flow temperature in C
3,094 5,279 7,500
30
60
90
00 hrs p.a.
Project goalsWith this project, the partners pursue the goal of testing all qualities of the system in a comprehensivemeasuring program. In addition to the usual measur-ing devices for temperature, flow and electric para-meters, a gas chromatograph is used that allows tojudge the reformation and conversion rates of eachgas treatment step. These are some central functionsof the measuring program:
Evidencing operational safetyElectric efficiency (approx. 35 percent), evidencing that the course is constant Efficiency of each component reformer, stack and inverterAging behavior and voltage dropPart load behaviorTheoretical degradation (conversion of all existingenergies into heat) after 40,000 hoursEvidencing long-term functional security of thestack and plant Review availability and reliabilityTransient and start-up behavior Optimum linkage into power and heat supply systems
The measurement program will take approximatelytwelve months. This phase will be followed by three-year continuous operation to allow conclusions onlong-term operating behavior.
Approval procedureThe technical review by the German Technical ControlAssociation TV Rhineland/Berlin-Brandenburg wascore to the approval process. The reviews comprisedindividual testing of components and groups, safetychecks and functional testing. Tests are being carriedout in compliance with both the new European direc-tive for pressure devices and the Canadian CSA (Cana-dian Standards Association) directive. Their aim is toconduct, if possible, all tests that will later be requiredfor the ultimate serial product.
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Berlin-Treptow heat plant
The fuel cell is run as an
integral part of the heat plant.
A bypass ties it into the district
heating system.
Cooling compartment
Fuel cell stack
Humidifier module
Shift reactor module
Electrical compartment
Steam reformer
DC/AC converter
Fuel cell container
All components needed to operate the fuel cell
are housed in a container. What must be added
are the connections to natural gas, heating,
demineralized water, nitrogen and compressed-
air pipes.
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Solutions for tomorrows world.
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Stand-alone, demand-guided power supply has ceased to be a utopia
Liberalization of the European power market has for many
companies thrown up the question whether energy supplies
in their usual form still tally with market developments.
Will investments in large-scale generation plant and extensive
distribution networks continue to pay back in future?
Future prospectsLarge power plants, not always loca-ted close to customers, have so farbeen the hallmark of power supply.Energy has been transported to usersover cost-intensive transmission anddistribution systems.
In addition, inner-city power plantshave been used in big cities such asBerlin or Hamburg. Besides producingpower, they have also served to provideheating services. This has created dis-trict heating systems with large groundcoverage.
Alternatives are now emerging forcommercial clients with the advent of stand-alone facilities such as windturbines, micro-turbines and blockheat and power plants. If linked to a modern communication system,
a complementary energy supply net-work with a focus on stand-alonefacilities can in future be installed.These facilities will evolve in responseto demand, clearly reducing invest-ment risks. Plans provide for numer-ous small generating plants operatedin an interconnected system of stand-alone service. Experts call them virtu-al power plants, or micro-grids. Fuelcells will be an essential componentof such stand-alone structures. Theywill be deployed close to the point ofuse for direct heat and power supply,with natural gas used as the predom-inant energy source in the initialphase. A precondition of this will bethat appropriate fuel cells can be easily integrated into existing supplysystems without detracting from the
well-being and living quality of con-sumers.
For large-scale uses such as satellitetowns or big residential buildings,mainly large generating units of thesize of the Berlin demonstration plantwill be employed, while small facilitiesare predestined for inner-city applica-tions where height limitations need to be respected. The plants will backup one another, and be linked throughthe existing public system or local distribution networks. An efficientcommunication system will monitoroperation of the individual compo-nents.
Fuel cellHeat
Electricity Natural gas
Fuel cellHeat
250 kWel 1 to 5 kWel
Fuel cell
Fuel cells for stand-alone energy supply
For larger-scale loads, plants with larger-sized
capacities are used. Where served facilities
are small, it is recommendable to deploy units
with their output limited to the demand of
the respective facility.
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An important contribution towardpractical applicationFuel cells will play a key role as anelement of a future, sustainable ener-gy supply infrastructure because theyare energy-efficient and environmen-tally friendly. Their successful marketlaunch will largely depend on theavailability of products suitable forpractical use. Besides further devel-opment work, this will require practi-cal testing. The Berlin demonstrationproject has made an important con-tribution in this respect. It is open forvisits on the grounds of the fuel cellexhibition.
The Hessian fuel cell a demonstra-tion project 1993 1998The project of Hessische Elektrizitts-AG (HEAG), Darmstadt, and the Insti-tute of Chemical Technology of theDarmstadt Technical Universityenjoyed financial assistance from theHessian Ministry of Environment,Energy, Youth, Family and Health:During the project term between 29June 1993 and 28 April 1998, the fuelcell generated an electric power out-put of 5,462,951kWhel and a thermaloutput of 6,866,506 kWhth.
Pay a visit to Bewags fuel cell exhibitionEichenstrasse 7/corner of Puschkinallee12435 Berlin-TreptowS-Bahn station: Treptower ParkSubway station: Schlesisches Tor/ Bus 265Open Mondays through Fridays 10:00 to 18:00 hours,Saturdays and Sundays 13:00 to 17:00 hoursPhone +49 30-267-111 38Fax +49 30-267-1 03 13
The changed energy market environments
and availability of new, efficient generation
systems suggest that the structures of energy
supply will shift.
A rsum.
Fuel cells make an important contribution to energy supply in the 21st century
The history of the fuel cell
Fuel cell first described by Sir William Grove
First U.S. fuel cell patent (Vergnes)
Nernst for the first time applies yttri-um-doped zirconium for a bulb
Reid for the first time describes analkaline fuel cell
W. Schottky delivers a theoreticaltreatise on SOFCs
Baur and Preis for the first time publish SOFC experience
F. T. Bacon presents a 150W fuel cell
6 kW high-pressure fuel cell of F. T. Bacon
The Westinghouse SOFC programstarts
The Allis Charmers ManufacturingCompany uses a 15 kW fuel cell todrive a tractor
Fuel cell development for the Apollomission starts (1.4 kW, 200 C, potashlye, 3.5 bar)
1 kW PEMFC plant for the Geminispace program
Double electrode concept for alkalinefuel cells by Justl
United Technology Corp. (UTC) produces a 12.5 kW PAFC
UTC in New York produces a 4.8 MW plant
Westinghouse manufactures a 5 kW SOFC stack
11 MW PAFC plant in Japan
Westinghouse manufactures a 25 kW SOFC plant
Energy Research Corp. (ERC) manufactures a 2 MW MCFC plant
1839
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Fuel cellexhibition
Eichenstrasse /Puschkinallee 52
Puschkinallee
Schlesisches Tor
Treptower Park
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E-mail
Internet
Bewag Aktiengesellschaft
Puschkinallee 52
D 12435 Berlin
www.bewag.de
Phone
Fax
E-mail
Internet
Fuel cell exhibition
Eichenstrasse 7/corner of Puschkinallee
12435 Berlin-Treptow
S-Bahn station:Treptower Park
Subway station: Schlesisches Tor / Bus 265
Open Mondays through Fridays
10:00 to 18:00 hours,
Saturdays and Sundays
13:00 to 17:00 hours
Information:
+49 30-267-111 38
+49 30-267-1 03 13
www.innovation-brennstoffzelle.de
www.fuelcellpark.com May
200
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