Road haulage can conserve more energy
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wrong. Out of the total amount of 130 million tons of mineral oil consumed in the Federal Republic of Germany in 1978 7.3 million tons were attributable to road haulage as a whole, corresponding to 5.6%. Longdistance haulage — which always used to be mentioned first in the discussion of trans' port energy policy — consumed 1..56 million tons, corresponding to 1.2%.
By comparison, the sectors of private central heating (33%) and industrial production (25%) catch our eye with quite different dimensions. Reduction of mineral oil consumption of these fields by only 10% would result in an energy saving several times higher than that which could be achieved by a 10% fuel reduction of road haulage, with more or less similar negative side effects. He who seriously wants to reduce mineral oil consumption, balancing this reduction against its side effects, has little scope in the sphere of road haulage.
The automobile industry is a pioneer in the development of energy saving measures. This fact is based on the high percentage of fuel costs in the overall cost of the lorry operation: In the Federal Republic of Germany the fuel costs amoun ting to 17-20% are higher than the comparable vehicle purchase price — and who does not look with special interest on the price of a new vehicle! With the exorbitant increase of the diesel fuel price in the last few months, this factor becomes even more important.
The automobile industry successfully tried to work against this tendency by reducing fuel consumption.
In order to decrease air resistance, cabs have been fitted with airshields and, front aprons. At present, the industry is examining the possibility of lowering air resistance rates by a better lateral casing and a panelling of the gap between unit and trailer.
Through a series of measures the engine constructors achieved considerable results. The optimum co-ordination of engine power, legal provisions, the method of driving and — last, but not least — the real requirements of transport operation has .come within reach.
We are all perfectly aware that depending on the drivers' 'handling of the vehicle and his -feeling", the amount of fuel consumed can vary considerably. In the Federal Republic of Germany — and as I know, in other countries, too — special training methods have been developed, in order to familiarize the drivers with the secrets of minimal fuel consumption.
The main. points of this training programme are: • driving of a fully loaded road train of a maximum permissible weight of 38 tons on a test road before training begins and measurement of fuel consump • discussion of the factors influencing fuel consumption.
1111 driving of the same vehicle on the same test road at the end of the seminar and measuring fuel consumption.
The excellent results of the seminar after a three day course are amazing. The fuel consumption of all drivers trained so far has decreased by between 5.3 And 15.5%, and on an average by 9.9%. It must be pointed out that even the most experienced drivers could improve by training.
Test driving should be over a distance lot approximately 30 to 50 kms, (20-30 miles) comprising all types of roads.
The time factor is of considerable importance, and must not be disregarded. In all seminars organized so far by the associations of the German road transport industry, the same average speed has been maintained in principle. In many cases a part of any fuel price increases can be absorbed by additional training. However, considering the high number of commercial vehicle drivers in the country, such training programmes can only be performed gradually. For this reason, concrete overall .economical effects of the drivers' training cannot be expected overnight naturally, but like the training gradually.
Improved driving techiques are easily acquired. They are basically slow acceleration, driving in the lower speed range and changing of gears as seldom as possible, and driving in a defensive and far-sighted way and consequently less braking.
During the last few years, the automobile industry has developed apparatus not only for measuring precise fuel consumption, but also to give the driver signs en route for the optimum vehicle handling relating to fuel consumption. Useful devices are today offered to the driver, ranging from a mark on the tachometer ("driving within the green range") to rather complicated 'special apparatus, partly still in process of development. They all relate to reduced energy consumption as a function of vehicle handling.
The' most economical fuel consumption is achieved, when the vehicles are used to, capacity. The operating costs — in this case the consumption for the movement of the vehicle's dead weight — are thereby allo cated to more units. For this reason, hauliers have been endeavouring for many years to maintain an optimum average utilization rate of 60% still a dreamlike value. Nevertheless, even better results can be achieved in this field through co-operation between the transport operators and through a freight clearing service operated on an electronic data processing basis.
Surplus capacity necessarily leads to a lower utilization rate and higher costs. It is an inherent feature of the road haulage sector — like internal navigation or aviation — that a series of special characteristics automatically provokes surplus capacity. That is unless the State regulates competition by measures to be adopted in the fields of capacity and prices. The 'answer is not, to confer special benefits to the transport operators through artificially tightened capacities and artificially increased prices. The answer is rather, to ensure that optimum services are offered to the national economy by avoiding cut throat competition, and to guarantee the optimum use of limited resource, which are required for production — in particular mineral oil. This is why I clearly plead for measures to be taken in the spheres of capacity and prices — also and above all under the aspect of rational energy use in road haulage — like those existing for many years with favourable overall economical results not only in: the Federal Republic of Germany but also in other European countries, especially in France and the Netherlands.
Fuel consumption of commercial vehicles does not increase in proportion to the in creasing itilization rate and. total weight, but at a lower rate.
This means that the specific fuel consumption (gallons per 100 ton-miles) decreases with an in creasing total weight. As the transport volume does not depend on the loading space off ered but on the overall economical development, the fuel consumption of a given national economy can be reduced through higher total weights, whereas road haulage as such remains unchanged. When, for example, the total weight of a road train is increased from 32 to 42 tons, .the specific fuel consumption decreases by approximately 20%, the utilization rate remaining at 100%.
The explanation of this phenomenon is quite simple. With the increasing total weight, the rolling resistance increases, too, but not the air resistance. The major part of the fuel is consumed in breaking the air resistance, which increases at a higher percentage than speed. For this reason, the specific fuel consumption must decrease, when the total weight is increased and the design of the vehicle remains unchanged.
Therefore we have to deal seriously and rigorously with the apprehensions over the disadvantages of higher total weights for commercial vehicles. These fears comprise still higher road congestion, still more increased road destruction and a higher' risk of decreased road safety. Do these negative effects really exist, and are they so important that we have to give up the advantages of higher total weights, mainly in the energy field?
It is in the interest of the
owners of commercial vehicle! that road congestion will ID( reduced. Less vehicles on tht roads mean better transit anc less journey-time, and it is pre cisely this journey-time or which the commercial efficienc) of the utilized lorries depends. , A higher Maximum iota weight .of the commercia vehicles allows the transport ol more payload per vehicle. ThE increase from 32 to 42 tons, foi example, would result in a payload increase of 8 to 8.5 tons in the case of 5 axles. As the demand for transport services does not depend on the supply to transport space and load capacity, such change would necessarily lead to a reduced number of vehicles required. By this, road congestion would be reduced accordingly.
About 20 years ago, the AASHO-Road-Test carried out in the United States ascertained under the then prevailing conditions and relationship between axle weight and road destruction. Meanwhile, technical development as well as research has advanced considerably. Today we know that not only the static axle weight, but also suspension, number of tyres per axle, tyre inflation pressure and shock absorbing play an essential part in road wear. Modern vehicles already cause much less road wear than those used. at that time in the United States, and here in Europe, too. By additional improvements, through air suspension and the increased use of twin tyres, road wear attributable to vehicles between 42 and 44 tons can be maintained at a lower rate than that of today's road trains of 32 tons and 4 axles or of 38 tons and 5 axles respectively, even
lough the total weight in-eases.
Because of higher total Peights road wear is not bound ) increase; on the contrary, it 3n be decreased further by nproved techniques, despite igher total weights.
It is sometimes said that iere is a clear relationship betten the total weight and the equency of accidents which, ; they declare, grows with an Icreasing total weight, This :atement was partly correct at le beginning of the sixties, is 10 more valid today. Since 965 the accident rate of cornlercial road vehicles has been lecreasing in all weight cateories, in absolute and in elative terms. In the Federal Iepublic of Germany the inolvement of lorries in road ccidents with personal injury, eferred to ton-miles, has dereased by 50%.
The relative accident involve
ment rate of the commercial vehicles in the European countries is from 10 to 20% under that of all other vehicles categories. This includes all existing weight categories of lorries and road trains, as .far as they have been statisticized separately.
There is no indication that this tendency would be affected prejudicially by higher total weights or higher axle weights. On the contrary there are intensified efforts made by the owners of commercial vehicles with a view to contributing to
road safety. They have adopted the motto: -Every accident is one accident too many-. They are backed by better training of the professional driver, the decreasing number of vehicles as a result of increasing maximum total weight, and the better coefficient of friction between tyre and road surface bound to higher axle weights.
There is no doubt in the minds of transport people that it is to the interest of all of us to keep energy consumption as low as possible, without considerably lowering the standard of living of our fellow citizens. In road haulage certain reserves still exist, and we must do all in our power to make use of them. We are not only obliged to do so in consideration of the increasing diesel fuel prices but also of the far-sighted understanding that our earth has supplies of mineral oil only for a few more decades. We could almost say mineral oil is more precious than gold.
The subject given to me for handling today did not deal with the possibilities of economizing fuel in the order of 10 to 20% by increasing roadbuilding, by better traffic routing, by better traffic signals and light and by clearer traffic information through traffic signs and topical broadcast messages. But we, too, have many opportunities to co-operate successfully in the solution of this world-wide task assigned to our generation. Everybody can contribute to achieve this goal.
The automobile industry can contribute by further improving vehicles with reduced air resistance and the specific fuel consumption of the engines.
The driver can play his part by better training in defensive and far-sighted driving.
The transport operation can help by introducing an even better transport organization.
The State must accept that there is undoubtedly a case for higher weights and dimensions.
We must all avoid cutthroat competition.
We have a golden opportunity to cope with the present problems in the fields of environmental influences, road safety and, above all, energy consumption, if we jointly make full use of all possibilities to save fuel. And there is still a great number of these possibilities. We must seize our chance.
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