[In which Peter Clark gives us the benefit of his researches and experiences. Although this subject is not of immediate interest to the enthusiast, his desire to motor as much as possible forces him to consider the alternative fuels, albeit only to increase his range of business motoring, for apparently the rubber situation necessitates banning the use of coal and producer gas for “pleasure” motoring. Although the author points out in a covering letter to me that he is no oracle and is only as well-informed as he has found it possible to be in the face of the prevailing secrecy, nevertheless this is the best account of the subject we have read. – Ed.]
The Ministry of Mines have recently been collecting information as to the percentage of producer gas plants, fitted to commercial vehicles in the past, which are still in use. I am afraid they will have received a rude shock: my personal guess is “less than 5 per cent.” You have only to talk to any lorry owner who has had practical experience of producer gas to form a similar estimate. Why, then, you may ask, do the Government talk of fitting a further 10,000 vehicles with this mode of propulsion, and why is this the only form of alternative fuel to which they have given their somewhat lukewarm blessing?
Being no politician I cannot attempt to assess the true Governmental outlook on these matters. I shall merely outline a few suggestions which have been made from time to time, none of them being necessarily my own opinion. Before doing so, I must inevitably remark that, so far as private passenger vehicles are concerned, there is no doubt whatever as to the Government’s attitude: by hook or by crook they want them off the road.
What is the Government’s attitude towards road haulage? An extreme view is that the Government, being railway to the roots, wants every lorry off the roads as well as private cars, and in sponsoring an alternative fuel has been careful to choose one which doesn’t work; that 10,000 vehicles on producer gas would be 10,000 vehicles virtually immobilised and a further 100,000 tons of goods a day swelling the congestion (and the revenue) of the railways. Let us, however, take a more charitable view and assume that the Government is not plumb crazy. Can their faith in producer gas be justified? Were the hundreds of disgruntled ex-users wrong, or too hasty, in their condemnation?
Before proceeding to a more detailed study of producer gas possibilities let us run through the other alternative fuels. I expect I shall forget one or more of them, but they are mostly not available and/or not much good, so it does not greatly matter if I do. The exception to this rather sweeping condemnation is, of course, town gas, which, within the limitations of a range rarely exceeding 20 miles per balloonful, gives quite reasonable results; however, even firms engaged on work of high priority can obtain no assurance whatever of continuity of supply if they convert staff cars to run on gas, which effectively discourages them from doing so.
Compressed town gas is a very much more interesting proposition, but although masses of pig iron are apparently available for the construction of producer gas plants in the most blacksmithian manner, one is told that metal is not available for any greatly increased production of high-pressure gas cylinders. In addition, the number of gas undertakings with suitable compressors is very limited. Neither of these factors, however, would have stood in the way of a Government determined to see goods vehicles running on compressed gas.
Another combustible gas which liquefies at a high pressure and could be stored in the same kind of cylinders is acetylene. Calcium carbide is at present almost entirely an imported product, but I know of no insuperable reason why it could not be made here. However, the fact at the moment is that carbide, although for commercial purposes in plentiful supply, is not in sufficient supply to meet any considerable new demand for road transport use. Thus very little development work has been done in this country, although in Switzerland great progress has been made. Unfortunately, also, what little experimental work has been done here (by that indefatigable carburation expert, Mr. Arnott, of Carburetters, Ltd.) has led to the development of a plant calling for one type of carbide, a finely graded material of sand-like consistency, free from both dust and lumps, which definitely is unobtainable except in small and erratic lots. Moreover, Messrs. Carburetters, Ltd., are so pressed with other war work that they find it impossible to answer correspondence regarding alternative fuel problems except “when circumstances permit.” As circumstances have not yet permitted them to answer an enquiry I made last March, I must regretfully cross acetylene off my list of practicable fuels.
Finally we come to the methane-butane gases, which have been described as the perfect fuel. Here we at once encounter an air of deepest mystery, which starts with the frantic anxiety of the distributing companies to convince you that it is not possible to run a car satisfactorily on their product. An official of one company even went so far as to make certain statements, in a letter to one of the national motoring weeklies, which the aforesaid Mr. Arnott quite rightly denounced as downright falsehoods. I do not know what is at the back of this most unseemly reticence, but my (mess is no worse than the next man’s. Methane, the “sewage gas,” would not in itself give a good performance, as its calorific value is too low; it has to be reinforced with a suitable admixture of butane, or even propane, which have much higher calorific values. These gases are by-products of petroleum refining, and there may well be reasons why a widespread increase in their production would be impracticable or unwelcome to the vested interests of the petrol world. Two things remain to be said. First, it is not very convincing to be told that metal is not available for this type of gas bottles; these gases liquefy at 25 lb. or less, so that a very modest specification would suffice. Secondly, a bold and detailed publication of the truth would do no harm and a lot of good. The present air of mystery leads everyone to think the worst.
Well, we have ruled them all out except producer gas, and as I see it the least bitter comment one can make on the Government is that they have seen fit to avoid the development of several fuels more promising than producer gas. I almost forgot to mention creosote and other home-produced alternative light fuels known affectionately to area and sub-area petroleum officers as “Alf.” Deep in the furthermost recesses of their most dusty pigeon-holes these harassed gentlemen have several closely typed sheets of foolscap telling them how to allot “bonus” coupons to patriotic hauliers using given percentages of “Alf.” Whether or not a similar concession could be extended to private passenger cars on essential work was a question the authorities could never answer. Not that it mattered much, for so far as I know “Alf” never existed other than on paper; at all events the country’s largest producers of creosote and other coal tar derivatives had never heard of him and could offer nothing suitable.
So, as I said before, we come to producer gas. And its troubles and difficulties can all be summed up in the one word “fuel.” Using the compressed charcoal ring-shaped biscuit product at Rouen and elsewhere as a by-product of wood alcohol “petrol,” French users of producer gas had tolerable results for many years, as did users in other European countries where timber and its by-products were plentiful. In England we had to rely on coke or anthracite derivatives.
The first gas plant I remember was a Koehla fitted to a Humber car in about 1932, when my friend Montague Lambert became associated with the introduction of this plant to England. Some readers may remember the car competing in the R.A.C. and other rallies about that time. Needless to say, Lambert was careful to run on charcoal when in the public eye, for I well remember that the plant ran splendidly on that, but was most troublesome on anything else.
Ten years have passed since then, and, fuel research being beyond the scope of individual firms, and the Government being disinterested, Koehla and the others were all forced to devote themselves to attacking the problem from the wrong end, i.e., filtration, instead of fuel. Filtration, as I said in a letter to The Motor recently, still consists of striking a workable compromise between a plentiful supply of dirty gas and a non-existent supply of clean gas. Koehla, with all respect, so elaborated their plant with the passing years that it must have offered very considerable suction resistance, and, moreover, its maintenance became so complicated that the average truck driver simply couldn’t compete.
That brings us to the other big snag – maintenance. Owing to the unsuitability of the available fuels, and the comparative complexity of the measures needed to counteract their deficiencies even tolerably well, maintenance assumes Gargantuan importance, and upon it hinges the success or failure of an operator with his plant.
However, let us return for the moment to fuel. By the early days of the war a good few “Government” producers were about on the roads, and a Government report on the “Emergency Conversion of Motor Vehicles to Producer Gas” had appeared. I hasten to add that in my humble opinion the report was a most excellent one so far as it went, and the producer was one of the simplest and least unreliable yet turned out. “So far as it went” – by this I refer chiefly to the continued use throughout the report of the word “emergency.” My impression is that the Committee had in mind only occasional use of producer gas when, in emergency, petrol supplies failed for a time; they did not, I feel sure, visualise the daily use of their plant as an alternative to petrol.
For this you may blame the Government if you wish, and the terms of reference convoking the Committee, but not the work of the individual Committee members. I am convinced that if their instructions had been to design a plant suitable for everyday use they would have insisted upon intensive and expensive fuel research. Actually there is a “Government Specification” for producer gas fuel, but it is not a yardstick of perfection, but rather a “plimsoll line”; adherence to it ensures that there will at any rate be no instantaneous disaster.
Just at this moment, as I write, much ballyhoo surrounds the “new” Government producer which, if it exists, is alleged to be immeasurably superior to its predecessor. Frankly I don’t believe it, unless the “new” producer is accompanied by a new fuel. The measure of success among the various proprietary plants on the market is, as in so many other things, not the achievement of a brilliantly different design, but the avoidance of obvious mistakes. When all, or nearly all, the latter have been disposed of, the fundamental difficulties arising from the fuel remain.
My first intimate personal experience with producer gas was, on behalf of my firm, with a cross-draught producer on a 4-ton six-wheeler Fordson. This at first cooled its tuyère off the ordinary engine cooling water and, as Mr. Fordson normally runs pretty hot, we soon had a spate of burnt-out tuyère and warped cylinder heads following on permanent boiling; a separate “blacksmith’s forge” cooling tank for the tuyère was substituted. Next we discovered the impossibility of cleaning out inaccessible pipework when it became coked up solid and had the layout considerably altered. Next we found that the filter was burning away and that the gases, which were thus obviously being inadequately cooled, were depositing in the induction manifold that which they ought to drop in the depositor box. I could continue ad nauseam, but you will see that all these troubles spring from the same old source – fuel. The plant strove valiantly to dispose of by-products which should never have been produced.
Results on my “D.6/70” Delage were not dissimilar; indeed, I have been greatly struck by the remarkable identity, not of relative performance by comparison with the petrol performance of the same vehicle, but of actual performance given by all vehicles on producer gas. My supercharged 8-h.p. Ford, of which some illustrations are given in these pages, has an almost exactly identical performance on gas to that of the Delage (2.75-litres unsupercharged).
If I could have two gas producer trailers, use them alternate days, and have a trusty retainer servicing the “other” trailer carefully each day, producer gas could be almost 100 per cent. reliable. When I wrote recently to The Motor concerning certain difficulties I was experiencing with the supercharger (now largely overcome) a worthy gentleman well known to us all wrote under the nom-de-guerre of “Gas Rolls, Meopham,” saying that his gas machine would go 150 miles with no attention beyond the addition at the start of the appropriate fuel and water. So will mine, but if called upon to do 150 miles a day six days a week I wonder if “Gas-Rolls” would be so trouble free. Last Monday my transfer pipe from cooler to filter tore away the welding on the filter. Yesterday a small chip of galvanising from the water tank blocked up the supply and the grate burned completely out before I was aware of any trouble. These difficulties force you to finish a journey on petrol and make it impossible for one gas plant per vehicle to drive that vehicle all the time.
But does all this condemn the Government scheme for those 10,000 vehicles as impracticable? Not necessarily. I believe that it can be done, by choosing trunk hauliers with depot to depot services and having them operate two or more gas trailers per vehicle. These trailers would be changed over at each journey’s end and a fresh trailer put on. Drivers should merely sit on the box and drive.
If this were done it is to be hoped (not very sanguinely) that some of the 20,000,000 gallons saved each year would be passed on to the struggling “private” motorist, to whom a car is so vital in the effective execution of his war effort.
[Peter Clark says he fully expects to be told that his opinions on this topical subject are arrant drivel, but trusts that critics will at least submit authoritative information about the alternative fuels discussed. With this proviso the correspondence columns are open! – Ed.]