Fuel cells electricity production

Figure 3.52. Efficiency of a reversible PEM fuel cell as a function of the amount (at. % or mol %) of Ir in the form of IrOj relative to Pt in the positive electrode catalyst, for fuel cell electricity production (EC) or for water electrolysis (WE). Also the product of the two efficiencies relevant for storage cycles is shown. The catalyst is otherwise similar to that of Fig. 3.51, with PTFE and Nation channels. (From T. loroi, K. Ya-suda, Z. Siroma, N. Fujiwara, Y. Miyazaki (2002). Thin film electrocatalyst layer for unitized regenerative polymer electrolyte fuel cell. J. Power Sources 112, 583-587. Used by permission from Elsevier. See also loroi et al. (2004).

Figure 5.96. Hourly conversion of hydrogen in the 2050 scenario. The curve varying regularly between 70 and 80 PJ/y is the (schematic) consumption by vehicles, and the strongly varying curves are the fuel cell electricity production in cases of insufficient direct power production. The lower part is direct use of hydrogen when production is ongoing, and the top part is based on hydrogen drawn from stores.

Allen, R. M. and H. R Bennetto. Microbial fuel cells Electricity production from carbohydrates. Applied Biochemistry and Biotechnology 39-40 27-40,1993. 

Allen, R.M. and Bennetto, H.P. (1993) Microbial fuel cells electricity production from carbohydrates. Appl. Biochem. Biotechnol. 39(2), 27-40. 

Electrochemical energy storage and conversion systems described in this chapter comprise batteries and fuel cells [6-11], In both systems, the energy-supplying processes occur at the phase boundary of the electrode-electrolyte interface moreover, the electron and ion transports are separate [6,8], Figures 8.1 and 8.2 schematically illustrate the electron and ion conductions in both the electrodes and the electrolyte in Daniel and fuel cells. The production of electrical energy by the conversion of chemical energy by means of an oxidation reaction at the anode and a reduction reaction at the cathode is also described. 

This is an example of the use of alkaline fuel cells for production of industrially interesting compounds rather than for electricity production (Alcaide et al, 2004). 

L Foscolo P. U. (1998) Production of Hydrogen-Rich Gas by Biomass Gasification Application to Small-Scale Fuel Cell Electricity Generation in Rural Areas, EU Final Report, Contract JOR3-CT95-0037... 

Fuel Cells Manufacture. The development and manufacture of several types of fuel cells for production of electric and heat energy to meet decentralize and centralize power supply of different power are planned. The special attention is given to zirconia ceramic fuel cells to supply residencies by electricity and heat to replace internal combustion engines in different transport applications to work in hybrid pairs with wind and solar generators, and gas turbines for production of oxygen for medical needs etc. 

The formed hydrogen by the water gas shift reaction can be electrochenticaUy oxidized in the fuel cell to water, electrical energy and heat. In solid oxide fuel cells the product water of the electrochemical oxidation of hydrogen is formed oti the anode site. This product water is available for the water gas shift reactimi on the anode side. At 650 to 850 °C reaction kinetics allows the water gas shift reaction without any catalyst or promoter. So carbon monoxide can be converted directly rai the anode side of the SOFC without any extra catalyst for promoting the water gas shift reaction. No extra converter is needed for the water gas shift reaction in SOFC fuel-cell heating appliances, which reduces the system effort. 

Both produce electrical enei. The reactants are added to a fuel cell and products are removed. A battery is usually sealed or self-contained. 

Electrochemists study the chemical changes produced by electricity, but they are also concerned with the generation of electric currents due to the transformations of chemical substances. Whereas traditional electrochemists investigated such phenomena as electrolysis, modern electrochemists have broadened and deepened their interdisciplinary field to include theories of ionic solutions and solvation. This theoretical knowledge has led to such practical applications as efficient batteries and fuel cells, the production and protection of metals, and the electrochemical engineering of nanomaterials and devices that have great importance in electronics, optics, and ceramics. 

What rate of car production would the current world production of Pt sustain The world production of Pt was 200 tons per year in 2012. If 50% of the Pt production were to be diverted for the manufacturing of fuel cell electric vehicles, it would suffice to produce 6 M vehicles. The current annual production of cars is 60 M. Thus, even under bold commercialization scenarios, the Pt requirement would drastically curtail the contribution of PEFC technology to the world car production. A further reduction of the Pt requirement by a factor 10 would be a game changer. 

Finally, the best alternatives in the near term for fuel cell electric vehicles include light naphtha or alkylate refinery streams liquid hydrocarbons derived from natural gas or as production, storage, and distribution systems develop, hydrogen. 

A regenerative fuel cell system can also be a single electrochemical cell in which both the oxidation of fuels (i.e., production of electric power) and reduction of CO2 (to obtain fuels) can be carried out by simply reversing the mode of operation. 

Fuel Cell Catalysts. Euel cells (qv) are electrochemical devices that convert the chemical energy of a fuel direcdy into electrical and thermal energy. The fuel cell, an environmentally clean method of power generation (qv), is more efficient than most other energy conversion systems. The main by-product is pure water. 

Electrochemical systems convert chemical and electrical energy through charge-transfer reactions. These reactions occur at the interface between two phases. Consequendy, an electrochemical ceU contains multiple phases, and surface phenomena are important. Electrochemical processes are sometimes divided into two categories electrolytic, where energy is supplied to the system, eg, the electrolysis of water and the production of aluminum and galvanic, where electrical energy is obtained from the system, eg, batteries (qv) and fuel cells (qv). 

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