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Ultimate reserves, on the other hand, represent the total volume of liquid petroleum which experts estimate will eventually be produced in this country. Just last year, the U.S. Geological Survey estimated that approximately 1 trillion barrels of crude oil and 75 billion barrels of natural gas liquids may eventually be found in this country through exploration. How much of this total will actually prove to be economically recoverable remains to be seen, but the Geá logical Survey estimates that at least 40 percent will eventually be brought to the surface. Thus, with liquid hydrocarbon production running at about 3.2 billion barrels per year, it is apparent why the Interior Department in their “An Appraisal of the Petroleum Industry of the United States," issued in January 1965 stated that "on the basis of these cold figures, it would appear that the United States is in no danger of running out of oil for many years."

Of course, in addition to conventional crude oil and natural gas liquid reserves, the shale deposits in the Green River formation in Colorado, Utah, and Wyoming will undoubtedly one day supplement our present sources of petroleum hydrocarbons. Experts currently estimate that the oil shale deposits in the United States represent a total of 2 trillion barrels of oil in place. And, besides these shale deposits, there are also the tar sand reserves in Canada which may contain an additional 600 billion barrels of petroleum energy.

While it is true that oil and natural gas are important sources of chemical raw materials, it should be pointed out that their manufacture is not being jeopardized by the continued consumption of liquid petroleum as a fuel. Currently, some 80 billion pounds of petrochemicals are being produced in this country—about 35 percent of the total organic chemicals manufactured in the United States. But the manufacture of these petrochemicals requires less than 5 percent of the crude oil we currently refine.

The remainder of our refined crude is primarily turned into fuel, both for heating and transportation. These are areas where petroleum has thus far proved to be the most economic and efficient fuel. Coal has already lost much of the residential heating and transportation markets—having been replaced by gas and oil. And as for atomic energy, AEC experts themselves admit that nuclear power cannot effectively and economically compete with petroleum as a fuel in motor vehicles or aircraft, or in the heating field-safety factors, the necessity of protective shields, and expense seem to rule out these markets for nuclear power. Just this past June, as a matter of fact, Dr. Glenn T. Seaborg, Chairman of the U.S. Atomic Energy Commission, had the following to say when addressing a meeting of the National Association of Manufacturers:

Nuclear energy will be used increasingly for those purposes to which it is best suited—the large-scale production of electricity. Other energy sources will find their growing uses in those areas to which they are best suited.

Thus, it seems apparent that liquid hydrocarbons will continue to be the prime supplier of our Nation's energy, as well as the raw material from which much of our organic chemicals are derived. Reserves appear adequate to meet both needs for many, many years to come.

Experience indicates that competition among fuels has stimulated the increased use of energy in this country and thus our economic

growth. Under such an environment, rather than a policy of end-use controls, the petroleum industry feels assured that it can meet the challenges that lie ahead. This is a belief apparently shared by the Department of the Interior which said in its "appraisal” last year

The data developed by this study reveal an industry that is healthy and vigorous and capable of meeting the requirements that will be placed upon it in the foreseeable future * * *. It is evident that the petroleum industry has the financial and technological capability to accomplish it.

Question 2: Realistically, what are the near term prospects for an economically competitive replacement for tetraethyl lead in gasoline?

Answer: On a realistic basis, the prospects for the discovery of an economically competitive replacement for lead antiknock compounds are very slim.

An extensive search for such a compound has been carried out on a multimillion-dollar-per-year scale by the antiknock manufacturers, petroleum refiners, and chemical companies since World War I. To date, this vast research effort has not produced a suitable alternative antiknock compound. The major technical requirements for such a compound are formidable. They are:

1. High antiknock effectiveness in a broad range of hydrocarbon types under a wide variety of engine operating conditions.

2. High solubility in a wide range of hydrocarbon types.

3. Negligible solubility in water which is present to some degree in all fuel systems.

4. Volatility characteristics permitting relatively uniform distribution to the various cylinders of the internal combustion engine.

5. Sufficient chemical stability to permit normal handling and storage both in the concentrated form and when blended with gasoline.

6. The ability to be consumed in typical engines without causing significant engine durability problems. Research for new antiknocks will, of course, continue. As new chemistry develops through basic research in universities, industry, and Government laboratories the new chemical compounds resulting from such research will be investigated as possible antiknocks. But, based on the present state of the art, the chances appear to be poor for a near term replacement for lead antiknocks.

Question 3: How does the present crude oil import policy affect the sulfur content of fuels for sale in the United States?

Answer: If the present crude oil import policy were relaxed, U.S. refiners would probably process more crude oil from the Middle East and from South America. Since these imported crudes generally contain a higher sulfur content and are heavier than domestic crudes, increased volumes of residual fuel with a higher sulfur content would be produced. It should be noted that among the imported crudes, Venezuela crudes contain somewhat less sulfur than Eastern Hemisphere production although they are generally higher than U.S. crudes. North African crudes are relatively low in sulfur, and to the extent they might be brought to the U.S. east coast refineries, they would tend to drop the sulfur content of residual fuels.

COMMENTS ON INDUSTRYWIDE, INDUSTRY-BY-INDUSTRY EFFLUENT

STANDARDS 1. Industrywide, industry-by-industry, effluent standards would be inconsistent with the current Federal Water Pollution Control Act which requires the establishment of water quality criteria in receiving streams to protect the legitimate uses of each section of major river basins.

2. Since all receiving waters cannot be used for all purposes and their capacity to assimilate treated wastes are highly variable, there should be no uniform effluent requirements for all industries. This would impose an unjustified burden on companies discharging effluents into a large stream with limited water uses and understate the requirements for a plant operating on low-volume streams of high quality.

3. It is equally obvious, however, that the establishment of receiving water quality criteria alone will not be sufficient to guide industries and municipalities as to the effluent targets that must be met to achieve the goals for the particular receiving stream. Ultimately, the total allowable pollution load on a particular stream must be established and allocated back to industrial and municipal dischargers.

4. The imposition of nationwide effluent standards would result in an unnecessary expense to the consuming public. The availability of water for industrial use is only one of many factors in an industrial operation. If we are going to legislate that this factor is exactly the same for everyone, everywhere, whether local conditions require it or not, then we might as well legislate to equalize all the other factors -such as labor costs, transportation, availability of raw materials, etc.

5. In the past it has been the prerogative of the individual plant to select treating methods to satisfy a condition in a stream at the most economical cost. Since stream conditions and flow vary for each individual stream and plant effluent volumes vary, the setting of a common effluent standard would result in unnecessary increased costs for many, but not all plants.

6. In this connection, industry should properly provide technical guidance to regulatory authorities in formulating programs for individual plant waste reduction. Industry is in the best position to assist in developing an equitable basis for allocating allowable waste loads among plants discharging into a particular receiving stream.

7. With respect to air pollution, the above principles apply as well to control of emissions to the atmosphere. Air quality criteria should be established as targets to be achieved. Individual air basins should then be studied from a meteorological, topographic, and population basis. An inventory of all emissions should be conducted and an equitable rollback of objectionable levels of pollutants prescribed where necessary.

8. During the course of the hearings, the question concerning the establishment of industrywide standards was raised a number of times. This concept was discussed by Dr. Abel Wolman during his “summation of the hearings. We concur most wḥoleheartedly with "his conclusion that industrywide standards would not be practical.

RESPONSES TO QUESTIONS OF THE SUBCOMMITTEE ON SCIENCE, RESEARCH,

AND DEVELOPMENT BY DR. ARTHUR M. BUECHE, GENERAL ELECTRIC Co.

Question 1: Is the military space R. & D. on fuel cells and batteries compatible with specifications for these devices in transportation, or will special additional work be necessary?

Answer: The contribution to commercial fuel cells by space R. & D. is mainly the establishment of a technical base and a competent electrochemical development and production organization that can be reoriented to commercial fuel cell development after completion of space R. & D. There is the possibility of using a small portion of the materials and components, but modification is almost always necessary.

The contribution to commercial fuel cells by military R. & D. is greater than that from space R. & D. since the former R. & D. is usually oriented to air instead of oxygen operation. However, military R. & D. is usually directed toward fuel cells that use logistically available fuels, which are generally very "dirty" (containing lead or large amounts of sulfur). Also, military fuel cells must operate in a water-conservative manner. As a result of this required complexity, the fuel cells developed will be too expensive to penetrate the pricesensitive, transportation industry.

Specific R. & D. funds oriented toward power systems utilizing fuel cells to meet the different and less complex requirements of the commerical transportation industry will have to be spent by private industry or the Government before any significant strides can be made for commercial transportation. A substantial service test program similar to the military and space programs will be necessary to prove applicability to commercial vehicular systems.

(For additional information, please note the following article, “Fuel Cells and Fuel Batteries. An Engineering View.”)

FUEL CELLS AND FUEL BATTERIES-AN ENGINEERING VIEW

(By H. A. Liebhafsky, General Electric Research and Development Center,

Schenectady, N.Y.) This is a welcome opportunity to attempt a paper on fuel cells primarily for electrical and electronic engineers, who may some day be joined by a new kind of engineer—the electrochemical engineer—if fuel batteries attain their expected usefulness. The kind of problems the new engineer will have to face are implicit in the questions and answers below.

WHAT IS A FUEL CELL? A FUEL BATTERY?

Fuel in its classic sense ought to be the key word in these definitions. Fuel cells and fuel batteries ought to react conventional fuels by which we mean the fossil fuels and substances readily derived therefrom) electrochemically with oxygen, preferably from air. A fuel cell thus is an electrochemical cell in which energy from such a reaction is converted directly and usefully into low-voltage direct-current electrical energy. Fuel cells electrically connected (in series, parallel, or series-parallel) make fuel batteries. The most common type of fuel cell is shown in Figure 1.

These definitions are more important than they seem. Though restrictive to make the subject manageable, they still include devices of great diversity. Fuel as used here excludes important substances often included, such as atomic "fuels" (e.g. uranium) and metals such as zinc or sodium (1).

The words directly and usefully imply that the device has an anode at which fuel is oxidized and a cathode at which oxygen is reduced; and that the conversion proceeds at voltages not greatly below the maximum possible, and at reasonably high current densities. Low-voltage and direct-current are important to the electrical engineer, who knows of course that electrical energy of this kind, although different from that ordinarily generated and transmitted, is of greatest importance to the electrochemical industry.

The reaction between conventional fuels and oxygen liberates only enough energy to give us about 1 volt per cell under ideal conditions. As Figure 1 shows, electrochemical reactions normally generate direct current. Schemes have been proposed to produce what has been loosely called alternating current from fuel cells, but the electrical engineer need not concern himself with such cells in the foreseeable future.

WHAT ARE THE IMPORTANT CONVENTIONAL FUELS ?

In order of decreasing reactivity: hydrogen (in a class by itself); compromise fuels; and hydrocarbons.

Hydrogen belongs by itself because it is simple and highly reactive, the first characteristic probably being responsible for the second. When hydrogen re acts at an anode, it loses only one electron per atom and forms simple products. This probably explains why hydrogen can give us high current densities (amps/sq. ft. of geometric electrode surface) with minimum loss of voltage from the theoretical. Current density and rate of electrochemical reaction are proportional.

Hydrogen has had a dominant position from the first in the fuel-cell field (see Figure 2), and hydrogen fuel cells and fuel batteries will be emphasized in this article. Hydrogen has serious disadvantages, among which only high cost and difficulties in handling and storage need be mentioned here. Because of these disadvantages, we must look to other fuels for the future.

The hydrocarbons, especially the liquid hydrocarbons, are among the most important and desirable of all fuels. Unfortunately they are low in anodic reactivity, and their reactions are complex and can lead to many products. They are strong where hydrogen is weak, and weak where hydrogen is strong. The direct hydrocarbon fuel cell is a most difficult research assignment, but its successful accomplishment entails rewards that would outweigh the difficulties.

As their name implies, compromise fuels are of reasonable reactivity, cost, availability, energy content, and not too difficult to handle or store. Methyl alcohol and ammonia are prime examples. Hydrazine would be for specialized applications were its price to drop ten-fold or more. The compromise fuels are likely to be the earliest successors to hydrogen in direct fuel batteries; hydrazine qualifies now for special military applications in which fuel cost is unimportant, and the toxicity of hydrazine can be tolerated.

So far we have not mentioned the commonest fossil fuel, coal. At the beginning of the century, scientists and engineers began to wonder whether the dream "electricity direct from coal" could be realized, whereupon the fuel cell, which had been almost dormant since Grove, suddenly became popular. In 1900, the overall efficiency of steam plants was only about 10%. At this efficiency, they would have offered much less serious competition to a fuel-battery centralstation than today, when this efficiency is 4 times as great. Figure 3 shows how far one man, Jacques, progressed in making electricity directly from a carbon much purer than coal. The caption of the figure explains why we need not consider coal seriously in direct fuel cells today.

CAN INERT FUELS, SUCH AS HYDROCARBONS, BE USED TODAY? Yes, but indirectly, by changing them to substances, mainly hydrogen, more reactive at fuel-cell anodes. Examples of such changes are the reaction of car-> bonaceous fuels with steam, which is being widely investigated, and the decomposition ("cracking") of ammonia, which will be used to provide hydrogen for a fuel-battery-powered submarine in Sweden. Indirect systems thus combine a chemical plant with a fuel battery, and the combination brings problems not present with the fuel battery alone. Ideally, the chemical process should be

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