10 Production and Application of Electrolytic Hydrogen: Present and Future L. J. NUTTALL
Direct Energy Conversion Programs, General Electric Company, 50 Fordham Road, Wilmington, MA 01887 Water electrolysis is an old technology for generating hydrogen. With the exception of a few special applications, however, it has not been economically competitive with steam reforming of natural gas. In 1975 there were approximately
1.8 x 1012 cu ft of hydrogen produced in the United States of which less than 1%
was produced by water electrolysis. The ratio on a world-wide basis was undoubtedly higher since the primary applications for electrolysis have been in areas where low cost hydroelectric power is available, i.e., Norway and Egypt. However, the percentage is still very small. The role of electrolysis in the production of hydrogen is certain to increase in future years, but the extent to which it does depends on a number of factors, including: • • •
Price and availability of natural gas relative to electric power Rate of development of non-fossil fuel energy sources Improvements in electrolyzer technology
One of the most significant current activities relating to this last item is a development program underway at General Electric to develop an advanced electrolysis technology for large scale commercial hydrogen generation using the solid polymer electrolyte type of cell originally developed for aerospace fuel cell and electrolysis applications. General Economics
At the present time hydrogen can be produced in a large, e.g., 100 MCF/D
(M = million, 106; K = thousand, 103) steam reforming plant for a cost in the
range of $6/MBTU (1). This compares with an estimated cost for electrolytic hydrogen of $15 to $20/MBTU, using current conventional electrolyzers, depending on the local cost of electrical power. The advanced solid polymer electrolyte electrolysis technology has the potential to reduce the cost for electrolytic hydrogen under comparable conditions to the range of $9-$13/MBTU. Figure 1 shows the calculated cost of hydrogen as a function of the electrolyzer plant cost, in dollars per KW (calculated from the higher heating value of the hydrogen produced — i.e., 10.7 SCFH 1 KW) of output and the overall system efficiency (ratio of KW output to the electrical power input), for an electric power cost of 0-8412-0522-l/80/47-116-191$05.50 © 1980 American Chemical Society
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hydrogen: production and marketing
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