Efficiency of fuel cells pdf

The higher efficiency of fuel cells is a consequence of the. This makes it difficult for researchers to compare devices on an equivalent basis. This initiative, supported by legislation in the energy policy act of 2005 epact 2005 and the advanced energy initiative of 2006, aims to develop hydrogen, fuel cell and infrastructure technologies to make fuel cell vehicles. This energy efficiency number is based on the lower heating value of hydrogen. Increased fuel cell output voltage enables reduction in the size of the electric motor, as well as in the number of fuel cells.

In gen eral, these efficiencies are not surpassing 50 % for the most efficient engines e. Yoneyama railway technical research institute, tokyo, japan 1. Low cost, high efficiency, reversible fuel cell systems nrel. Figure 16 combining the sofc with a gas turbine engine to improve efficiency. Fuel cell efficiency how fuel cells work howstuffworks. By comparing a fuelcellpowered car to a gasolineenginepowered car and a batterypowered car, you can see how fuel cells might improve the efficiency of cars today. To push the efficiency even higher, a fuel cell can be coupled with a combined heat and power system that uses the cells waste heat for heating or cooling applications.

In fuel cell mode, cells and stacks have been repeatedly demonstrated to be capable of operation on either hydrogensteam fuel mixtures or on reformed hydrocarbon mixtures. Fuel cell efficiency since fuel cells use materials that are typically burnt to release their energy,gy, y the fuel cell efficiency is described as the ratio of the electrical energy produced to the heat that is produced by burning the fuel its enthalpy of formation or. Nov 01, 2004 this report documents the status of the us department of energys fuel cells program as of the end of fy 87. Water gas shift and preferential oxidation, ward tegrotenhuis, pnnl pdf 390 kb. The fuel cell efficiency for hydrogenoxygen fuel cells can be obtained by dividing the cell voltage at operation by 1. Pdf the basic principles of work of proton exchange membrane fuel cell pemfc are presented. In the1960s, international fuel cells in windsor connecticut developed a fuel cell power. In contrast to reciprocating engines and gas turbines, fuel cells generate electricity without combusting the fuel. Internal fuel reforming fuel flexibility batteryfuel cell integratiom component requirements power density comparable with hydrogen fuel cells combining electrocatalysis and fuel reforming catalysis working below 550 c with no coking issues non or extremely low pt catalysts adaptable to different liquid fuels 7. These include short active lifetimes, low power densities, and low efficiency due to normally only incorporating a single enzyme fig.

Seventh edition fuel cell handbook technical report. Fuel cell simple english wikipedia, the free encyclopedia. Combined heat and power technology fact sheets series. Fuel cells are mainly classified by the characteristics affecting their performance like the type of catalysts, electrolyte used, the fuel required and temperaturerange 1, 2. The figure includes both in service vehicles and those that have been retired during the evaluation. An introduction to fuel cell technology and economics. Mar 31, 2018 since publication of the first edition of fuel cell systems explained, three compelling drivers have supported the continuing development of fuel cell technology. In both batteries and fuel cells two electrodes, an anode and a cathode, are separated by an electrolyte. Energy efficiency and fuel consumption of fuel cells.

Although hydrogen fuel cells are currently used on a small scale, making them commercially available for largescale use requires improvements in two key areas. Grove utilized four cells, each containing hydrogen and oxygen, to produce electric power which was then used to split the water in. The efficiency and economics of the fuel cells have been analyzed in various load profiles and for various development and cost scenarios. The high operating temperature of sofc fuel cells makes it easier to integrate the reforming stage into the fuel cell device. Technologies and applications the open fuel cells journal, 20, volume 6 the ove rall cell efficiency is between 37% and 42% however, if the heated watersteam generat ed by the. Direct methanol fuel cells dmfc a fair amount of research is conducted in direct methanol fuel cells dmfc, which are characterised by reforming the methanol directly on the anode surface through the use of a suitable catalyst ptru c. Thermodynamic efficiency of hydrogen fuel cells youtube.

Fuel cell type common electrolyte operating temperature typical stack size efficiency applications advantages disadvantages polymer electrolyte membrane pem perfluoro sulfonic acid 50. Merewether abstract fuel cells are important future sources of electrical power and could contribute to a reduction in the amount of petro leum imported by the united states. Advanced high efficiency quick start fuel processor for transportation applications, prashant chintawar, nuvera fuel processors for pem fuel cells, levi thompson, u of michigan pdf 492 kb microchannel reformate cleanup. They can run on a wide range of fuels, ranging from gaseous fuels such as hydrogen and natural gas to liquid fuels such as methanol and gasoline. Since publication of the first edition of fuel cell systems explained, three compelling drivers have supported the continuing development of fuel cell technology. This much higher theoretical efficiency is what makes fuel cells attractive. By comparing a fuel cellpowered car to a gasolineenginepowered car and a batterypowered car, you can see how fuel cells might improve the efficiency of cars today. Enthalpy and entropy of hydrogen fuel cell reaction efficiency of hydrogen fuel cells by considering the higher heating value of hydrogen. Microbial fuel cell mfc research is a rapidly evolving field that lacks established terminology and methods for the analysis of system performance. Maximizing the efficiency and lifetime of fuel cells with. For a fuel cell the efficiency can be calculated from the. Fuel cells based on ethanol as fuel is one possible technology for vehicle applications, mainly due to the advantages of the fuel even if the fuel production highly affects the environmental benefits. A fuel cell makes electricity using the energy released by mixing fuel with air, a reaction which creates water and sometimes also carbon dioxide. This initiative, supported by legislation in the energy policy act of 2005 epact 2005 and the advanced energy initiative of 2006, aims to develop hydrogen, fuel cell and infrastructure technologies to make fuelcell vehicles.

Fuel cell technologies program february 2011 printed with a renewablesource ink on paper containing at least 50% wastepaper, including 10% post consumer waste. Fuel cells can operate at higher efficiencies than combustion engines, and can convert the chemical energy in the fuel to electrical energy with efficiencies of up to 60%. Each of these topics is discussed in more detail in the current state of the industry chapter. Vtt also uses gmp343 co 2 transmitters in their fuel cell related research. One measure of the energy conversion efficiency of a fuel cell is the ratio of the actual. As with other types of power plants, fuel cells can offer the benefits of cogeneration, known as combined heat and power chp. Nrels technology validation team analyzes hydrogen fuel cell electric vehicles fcevs operating in a realworld setting to identify the current status of the technology, compare it to department of energy doe performance and durability targets, and evaluate progress between multiple generations of technology, some of which will include commercial. Low cost, high efficiency, reversible fuel cell systems. Further, heat represents microscopically disorganized form of energy, while work or electrical energy is fully organized, by the second law of thermodynamics it is not possible to.

Plan as cost effective, highly efficient, and critical for overall success in the hydrogen program. Grove utilized four cells, each containing hydrogen and oxygen, to produce electric power which was then used to split the water in the smaller upper cell into hydrogen and oxygen. Vehicles were retired due to performance loss, end of fuel cell life, end of vehicle test, or other catastrophic failure unrelated to the fuel cell system. Seventh edition fuel cell handbook technical report osti. Department of energy office of fossil energy national energy technology laboratory p. Nov 05, 2015 a fuel cell s efficiency advantage is even more pronounced when the heat fuel cells produce is recovered in a combined heat and power chp system, which allows for overall energy efficiencies of up to 90 percent. The operating principle of a pem fuel cell is described in figure 1. Ethanol is the most used biofuel worldwide with an existing supply chain and infrastructure in many parts around the world.

Principles of operation a fuel cell works much like a battery. Pdf analyses of characteristics and efficiency of fuel cell. The hollow cylindrical cells have outside diameters of 56 mm. Figure 22 effect of fuel utilization on voltage efficiency and overall cell.

Fuel cells use an electrochemical process to convert the chemical energy in a fuel to electricity. Fuel cells have several benefits over conventional combustionbased technologies currently used in many power plants and passenger vehicles. Labcell 200 alkaline availabl e in 1, 2, 4, 8, and 16 cell stacks 0. Rational design can improve hydrogen fuel cell efficiency.

While fuel cells offer a much higher ideal thermodynamic efficiency of around 94% compared to a maximum of about 60% for internal combustion engines, there are. Oct 09, 2017 thermodynamic efficiency of hydrogen fuel cells. Energy efficiency and fuel consumption of fuel cells powered test railway vehicle k. A bottoming process, in that heat can be extracted in the production of electric power, cogeneration using fuel cells can represent a significant opportunity to increase the. The efficiency characteristics of fuel cells compared with other electric power generating systems are shown in. An introduction to fuel cells and hydrogen technology by brian cook, heliocentris vancouver, canada whereas the 19th century was the century of the steam engine and the 20th century was the century of the internal combustion engine, it is likely that the 21st century will be the century of the fuel cell. Fuel processors for pem fuel cells, levi thompson, university of michigan charm costeffective, highefficiency advanced reforming module, thomas m. Department of energys fuel cell technology program states that, as of 2011, fuel cells achieved 5359% efficiency at onequarter power and 4253% vehicle efficiency at full power, and a durability of over 120,000 km 75,000 mi with less than 10% degradation. The first practical application for fuel cells emerged in. For print copies of this fact sheet, please call the doe energy efficiency and. Fuel cells fuel cells are the most energy efficient devices for extracting power from fuels. Holmes, nuvera fuel cells pdf 403 kb platebased fuel processing system, david yee, catalytica energy systems, inc.

Fuel cell engine technology hydrogen fuel cell engines and related technologies. Capable of running on a variety of fuels, including hydrogen, natural gas, and biogas, fuel cells can provide clean power for applications ranging from less than a watt to multiple megawatts. Box 880 morgantown, west virginia 265070880 november 2004. Fuel cells have the advantages of high efficiency, low or even zero pollution, quiet operation, and fewer moving parts only pumps and fans to circulate coolant and reactant gases, respectively for greater reliability than internal combustion engines once fuel cell systems are welldeveloped.

The construction and analysis of mfcs requires knowledge of different scientific and engineering fields, ranging. The report consists of 1 an overview of the fuel cells program including a brief discussion of how fuel cells work. The first practical application for fuel cells emerged in the 1950s when fuel cells were used to provide onboard power for. Since all three types of cars have many of the same components tires, transmissions, et cetera, well ignore that part of the car and compare efficiencies up to the point. Fundamentals and applications wiley online library. Download the related vtt reference case and application note maximizing the efficiency and lifetime of fuel cells with optimum humidification pdf for more information.

Fuel cells work like a battery being constantly fed with fuel so it never runs out as long as you have enough fuel. Efficiency and economics of proton exchange membrane pem. Alternative sources of energy an introduction to fuel cells. Since solid oxide fuel cells operate at very high temperatures, there is no need for catalysts made from precious metals. A fuel cell chp system runs with 8095 percent efficiency. This means that individual fuel cells can be joined with one another to form stacks. Direct methanol fuel cells dmfc are a subset of pemfcs typically used for small portable power applications with a size range of about a subwatt to 100w and operating at 6090c. Abstract for the purpose of an environmental burden reduction and an improvement of energy efficiency, we. This report documents the status of the us department of energys fuel cells program as of the end of fy 87. The most common fuel for fuel cells is hydrogen, which when reacted with oxygen from air produces only water. Fuel cell electric vehicle evaluations hydrogen and fuel. Stationary fuel cell power systems with direct fuelcell. Hydrogen tank refilling takes 3 to 5 minutes, and the vehicle with.

Fuel cell electric vehicle durability and fuel cell. Fuel cells could potentially be used to replace conventional power equipment in many cases. Cell geometry figure 1 shows how passive cells operate in fuel cell and electrolysis modes. Fuel cells powered by pure hydrogen emit no harmful pollutants, only pure water. Fuel cell efficiency an overview sciencedirect topics. Workshops parallel to the development of the technology roadmap on hydrogen and fuel cells 11 table 2. Existing fcev fleet and targets announced by hydrogen initiatives table 4. An overview of fuel cells currently under development.

Fuel cells maximizing the efficiency and lifetime by using a warmed humidity measurement probe technology pem fuel cell has a low operating temperature fuel cell mfc research is a rapidly evolving field that lacks established terminology and methods for the analysis of system performance. Molten carbonate fuel cell mcfc, solid oxide fuel cell sofc are explained, describing. For the reaction of the fuel cell, this ideal efficiency is approximately 94%. An efficiency of around 50 to 60 percent can be expected when solid oxide fuel cells are used to convert fuel into electricity. They are electrochemi cal devices similar to a battery and consist of a container, an. Ethanol is the most used bio fuel worldwide with an existing supply chain and infrastructure in many parts around the world. Current performance of hydrogen systems in the transport sector table 3. In 2003, president bush announced a program called the hydrogen fuel initiative hfi during his state of the union address. In turn, these stacks can be combined into larger systems. First fuel cellfirst fuel cell 3 in 1839, william grove, a british jurist and amateur physicist, first discovered the principle of the fuel cell. Hydrogen generation and carbonmanagement technologies can be developed, which can significantly reduce pollutants and greenhouse gases from.