From the Rolls-Royce experimental archive: a quarter of a million communications from Rolls-Royce, 1906 to 1960's. Documents from the Sir Henry Royce Memorial Foundation (SHRMF).
Article from 'The Autocar' summarizing Professor Vivian Lewes's lectures on motor fuels, including petrol, benzole, and alcohol.
| Identifier | ExFiles\Box 32\1\ Scan032 | |
| Date | 6th March 1915 | |
| THE AUTOCAR, MARCH 6th, 1915. 253 Motor Fuels. Professor Vivian Lewes's Fothergill Lectures before the Society of Arts. ON February 15th and 22nd and March 1st Professor Vivian Lewes delivered lectures before the Royal Society of Arts on the subject of motor fuels. The lectures, of which we give a summary below, were followed with considerable interest, as might be expected in view of their authoritative nature. The first lecture was largely introductory and partly statistical. Great as has been the increase in the quantities of petrol imported annually into the United Kingdom between 1905 and 1912, the average increase was only about half of that for the years 1913 and 1914. In the latter year the imports reached the enormous volume of 120,000,000 gallons, in spite of the disturbing influences of the war—a great tribute to the work done by our Fleet in keeping open the seas. It might be supposed that the increase in quantity during 1914 was dependent largely on the enormous volumes of petrol used in the war for transport, aviation, and other purposes, but this idea is negated by the fact that up to the middle of August the imports were 83,000,000 gallons, and, therefore, no sudden increase in demand has manifested itself due to war demands. All the French ports have also been open for the importation of petrol, and it is known that in October France imported 2,250,000 gallons from America as against 800,000 gallons in October, 1913, so that probably most of the spirit used at the Front went direct into France, and would leave almost the whole of the 120,000,000 gallons imported into England untouched for military purposes. The latter figure does not include the imported Government liquid fuel supplies, which in 1914 amounted to 170,000,000 gallons, chiefly, no doubt, fuel oil, but also, probably, partly petrol. With the supplies from America open to us, and also those from the Dutch East Indies, we are not likely to experience a shortage of petrol for a long time. Similarly, Russia had the Galician oilfields and also could draw on Roumania if the supplies from Baku and the other oilfields on the Caspian do not give a sufficient supply. due to the new "cracking" processes largely used in America, which enabled a larger yield of petrol to be obtained. It was as sure as anything was sure that the amount of crude oil in the world is limited, and that the quantity becomes smaller and smaller. Some people estimated that the supply would give out in 300 years, and others in 150 years, but personally he did not look upon the exhaustion of the oil as any test whatever of the period for which it will remain commercially possible to be used. It was not the fact of there being oil which governed the market; it was the fact of that oil being in such a position that it could be readily brought up and marketed. It might be within fifty years that the oil would be at such a depth that it would not be commercially possible to deal in it. Hence the necessity for pressing forward our knowledge of substitutes. Another and even more important reason was that the petrol supply was at present in, so to speak, two hands, and it was impossible, without some fuel which could compete, to prevent the price being forced up to a false price. The last two years had been an excellent example of the value of putting our heart into this matter in checking prices. In 1913 there was a rapid advance, and great rumours of petrol reaching 2s. 6d. per gallon. Then came a strong agitation in favour of alcohol and benzole, and the result was that the price stopped at 1s. 9d. He did not suggest that this was the only factor, but it was an important one. The Yield of Benzole. Attention was first turned to benzole. The yield, however, of benzole in England, after sufficient purification for use in the engine, amounts only to an average of 1.8 gallons per ton of coal carbonised. If the whole of the coal carbonised in the country had the benzole collected, it would amount only to less than one-third of the quantity of petrol needed, and the total amount used in 1914 as motor spirit was only 9,000,000 gallons. Incidentally, Prof. Lewes mentioned that practically the whole of the benzole obtained from coke ovens was exported to Germany, the astute Germans replacing the old bee-hive ovens with recovery ovens free of cost, and taking payment in benzole, which they used to good effect in the aniline dye industry. Certain enthusiasts, he continued, were so very confident that benzole was to be the fuel of the future that they talked as if petrol was done for, but they had had a rude awakening, mainly on account of the small supplies available. In the days to come, continued Prof. Lewes, when benzole was done with and petrol was done with, the fuel of the future would be alcohol, and nothing but alcohol. The whole energy of the world comes from the sun, via vegetation, which is the great secondary battery which fixes that energy. In our coal and oil, nature stored up for us incalculable quantities of energy derived from the sun in the early carboniferous period. Both these sources, however, would be worked out at a period not very far ahead of the present century, in the sense that they would be too far down in the earth to be able to be dealt with commercially. In order to fix the energy of the sun's rays, we could only do it by vegetation and fermentation. Therefore, the rapid growth of grain and fermentation into alcohol was the only process available. Unfortunately, legislative restrictions prevented the manufacture of alcohol on a scale sufficiently large at the present moment. Germany Using 80% Alcohol. With Germany, however, things are very different. In the first place, Germany was dependent upon the same sources of supply as the Allies, but practically the whole of the oilfields of the world are closed, although Prof. Lewes thinks there is considerable "leakage" through Roumania. Enormous as the stores of petrol were in Germany, she has used them in the same typically extravagant manner as she has used everything else in this war, with the result that the pinch is now being rather badly felt. Nevertheless, there is quite sufficient quantity for the needs of the military and for aviation, as far as can be ascertained, but the use of petrol by private owners is prohibited. Consequently, private cars have been fitted with carburetters to use a mixture of home-made fuels. The Germans have utilised the knowledge they have gained of the possibilities of using alcohol, and are now employing a mixture containing 80% of alcohol and 20% of benzole, to each gallon of which is added 200 grains of napthalene. The napthalene is first dissolved in the benzole, which in turn is mixed with the alcohol. The resultant mixture, said Prof. Lewes, gives five-sixths of the power of petrol. The amount of alcohol and benzole at disposal in Germany is approximately estimated to be sufficient for a five months' supply. The World's Production of Crude Oil. On the general question of petrol substitutes, Prof. Lewes said the question might well be asked why it is necessary to have them at all, seeing that, great as had been the increase in the demand, the supply had kept pace with it. The real question, however, was, how long would this last? In 1912 the total world's products of crude oil amounted to 51 million tons, in 1913 it was 54 million tons, and in 1914 it was 57 million tons—practically an annual increase of 6%. The amount of petrol to be obtained from the crude oil was, on a liberal estimate, 10%, and this gave 5.7 million tons of petrol for 1914, or 1,700 million gallons. The United States last year used 1,200 million gallons, and we in England imported 120 million gallons. This only left 380 million gallons of petrol for the whole of the remainder of the world. This surely, he said, was a very strong reason why we should have other means of producing petrol. The supply and demand at present practically balanced, and this was Grandmotherly Legislation. Manufacture was hampered by grandmotherly legislation, with the result that the cost, which need only be sixpence per gallon, is at present 2s. 4d. or 2s. 5d. The necessity for denaturing the spirit so that it could not be used as a drink introduced disadvantages in the direction of setting up corrosion in the engine; but, as a matter of fact, when using alcohol containing the proper amount of the right kind of denaturing material no corrosion would be found to take place unless the engine was being run practically without load, which was not the case in practice. The thermal value of alcohol, however, was not more than half that of petrol or benzole. At the same time, it must not be overlooked that the heat factor is not of real importance. Efficiency of the engine was much more important, and this depended upon an entirely different set of conditions, all of which were in favour of alcohol. Whereas, for instance, with petrol, the compression could not go much beyond 70 lb. or 80 lb., with alcohol compressions as high as 200 lb. could be used without any fear of pre-ignition. Again, whereas 1 lb. of petrol required 15½ lb. | ||