Molten carbonate fuel cells advantages

For natural-gas-fuelled CHP plants, the same line of argumentation holds as for the stationary use of hydrogen from biomass. It is more reasonable to use natural gas directly than to convert it to hydrogen first and then to heat and electricity. High electrical efficiencies can be reached in the stationary sector by feeding natural gas to molten-carbonate fuel cells (MCFC) and solid-oxide fuel cells (SOFC). Molten-carbonate fuel cells have the added advantage of using C02 for the electrolyte (see also Chapter 13). 

Several types of fuel cells have been developed and are classified according to the electrolytes used alkaline fuel cells, molten carbonate fuel cells, phosphoric acid fuel cells (PAFCs), PEMFCs, and solid oxide fuel cells (SOFCs). As shown in Figure 1.3, the optimum operation temperatures of these fuel cells are different, and each type has different advantages and disadvantages. 

Molten carbonate fuel cells use a molten salt electrolyte of lithium and potassium carbonates and operate at about 650 °C. MCFCs promise high fuel-to-electricity efficiencies and the ability to consume coal-based fuels. A further advantage of the MCFC is the possibility of internal reforming due to the high operating temperatures (600-700 °C) and of using the waste heat in combined cycle power plants. 

Molten carbonate fuel cells are interesting candidates for stationary power generation networks, similar to the SOFC concept. The technology of the SOFC seems to be further developed and superior to MCFCs, shadowing the advantages that MCFCs can provide. Once SOFCs become ripe for commercialization, MCFCs will probably not be able to compete. 

Use chemical equations to explain how the molten carbonate fuel cell (MCFC) works. What are its advantages and its disadvantages ... 

Molten carbonate fuel cells (MCFCs) are one of the two most common high temperature fuel cells, operating at 600 to 700°C. The key advantage... 

Together with the solid-oxide fuel cells (SOFCs) considered in Chapter 8, molten-carbonate fuel cells (MCFCs) are representatives of a class of high-temperature fuel cells that have a working temperature of more than 600°C. High-temperature fuel cells have a number of advantages over other fuel cell types ... 

Molten carbonate fuel cell - The typical running temperature of a MCFC is around 650°C. Molten carbonate salt is used as the electrolyte. Due to the high working temperature, a MCFC can be fuelled with various kinds of fuel such as derived gas and natural gas without an external reformer. The corrosion effect of sulfur should be taken into consideration when choosing the type of fuel. High efficiency and non-noble catalyst are the major advantages of MCFC. To date, MCFC has retained more than 40% of the fuel cell market share. 

The molten carbonate fuel cell (MCFC) operates at high temperature, which is about 600-700 °C. It consists of two porous conductive electrodes in contact with an electrolyte of molten carbonate. This type of cell allows the internal reform. The main advantage of the MCFC is its high efficiency (50-60%) without external reformer and metal catalyst, due to the high operating temperature (Farooque Maru, 2001). This cell is intolerant to sulfur and its launching is slow, these are its main disadvantages. 

Molten KOH or NaOH is used as the electrolyte, which is contained within a metallic container. The metallic container acts as the cathode and a carbon rod dipped into electrolyte acts as both fuel and anode of the cell. Molten hydroxide electrolytes possess advantageous features such as high ionic conductivity, low overpotential and high carbon oxidation rate with a low operation temperature of 600°C for DCFC, which make its components fabrication economical. The dominant reaction product would be CO2 instead of CO. The ceU reactions are given as follows ... 

The DCFC with molten carbonate electrolytes are the most commercial type of fuel cells. Molten carbonate as an electrolyte has a number of advantages such as high ionic conductivity long-term stability of CO2 and catalysis of carbon oxidation. These DCFCs work at high operating temperatures of 600-850°C. Usually, mixed molten... 

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