Electric power is the way ahead
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Roger Kemp. the development manager of Lucas Electric Vehicles put the case for electrics
FOR 60 YEARS, from 1910 to the 1970's, the industrialised world worked on the assumption that there is an exhaustible supply of oil in the ground. Our way of life has been based on this assumption. The centralisation of production and concentration of housing away from the work place has developed hand in hand with a rapid growth in cheap tramsport. This growth has been accompanied by a dramatic shift from public transport to private transport both for people and goods. The turn of the century,city centres was dominated by the tram. Today city centres are dominated by the tram. Today city centres are dominated by the private car and urban motorways. A similar shift from public carriers to the dedicated lorry has been seen in freight transport.
The era of cheap oil is coming to an end and, in the transport business is planning for the next generation of transport.
Mr Kemp said he had no doubt that it was possible to manufacture synthetic crude oil from coal but that the South African process, which is sometimes held up as an example, has an energy efficiency of only 22 percent and produces more than its fair share of air pollution. "It is worth remembering that roughly 17 percent of our total energy input at present provides transport fuel" he said and argued that if this amount of energy has to be produced from coal, with a very low efficiency, then it will absorb most of the NCBs present output. "Either this output will have to be doubled or we will have to use our expanded programme of alternative enetgy sources to provide low grade heat.He said the use of a premium fuel, electricity, to provide low grade heat is not sensible energy management and he has no doubt that syncrude will provide an essential componen.t in transport fuel in future. But it was not the answer to all our problems.
After coal the next most important source is probably nuclear energy he said. At the moment nuclear power provides 4 percent of our sentenergy requirements. is likely to increase over the next few years. The output of nuclear energy can be used. He said in the transport field, the overall efficiency is very much higher if it is used to drive an electric vehicle than if it is used to make hydrogen or some other chemical that will eventually propel a liquid fuelled vehicle.
In many parts of the world water power is a major source of energy. In the UK hydro electricity provides perhaps 4 percent of our electricity and much less of our total energy supply. In the last few years increasing attention has been paid to renewable energy resources. Various wave energy devices have been proposed and are being experimented with around this coast. Typical ratings of these devices are 50 kW/m. This implies machines tens of kilometers in length to be equivalent to a Modern large power station. Other engineers have suggested windmills and tidal barrages where a huge water-turbine is installed in a large dam in a major estuary.
An even more outlandish 'example of technology being investigated in the USA and Japan exploits the difference in temperature between hot and cold sea-water. A huge generating buoy anchored in the deep ocean the temp rature difference between the warm water at the top and the cool water at the bottom causes flows in ammonia gas filling the active part of the device which in turn operates a turbine to generate electricity.
There are many outlandish schemes about for producing electricity, he said, but singled out two — the first is the fermentation of sewage and the second growing Prolific plants that can be decomposed with the evolution of methane.
. "My guess is that these alternative technological solutions will, in about 30 or 40 years time, supply at the most 20 percent of our total energy needs mainly as high-grade electrical energy. It would be prudent if this high-grade energy, could be used for applications such as transport where such a ''highly refined" type of energy is needed," he said.
Talk of electric vehicles usually means trams, trolley buses and milk floats he said, but reminded the audience that at the turn of the century electric vehicles occupied a more important role on the transport scene than did internal cornbustion engine vehicles. However, supplies of cheap oil had led to the rapid development of the internal combustion engine and the electric vehicle was left behind.
When comparing costs of electrically propelled vehicles and diesel propelled vehicles it was very difficult to ignore the influence of road tax and perhaps inappropriate electricity tariffs he said. He explained that British Rail negotiates bulk electricity tariffs with the CEGB and abviously does not pay road tax on their diesel fuel. He thought that a comparison of their operating costs was instructive. Last year's paper on electrification shows very much lower operating costs for electric vehicles than for diesel vehicles. BR finds that the maintenance cost of an electric vehicle is only a fraction of the maintenance cost of a diesel powered vehicle. "Maintenance costs are skilled labour and there cannot be many transport managers who can way that they have adequate supplies of that resource," he said.
The Lucas development programme, for electric vehicles started about 10 years ago when advanced battery development required a test bed to try out a zinc-air battery.
The battery was not a success, but the vehicle was, even shen run on lead-acid batteries. In the original vehicle, a Bedford CA van, the batteries occupied the load space. An improved design located the batteries in a separate compartment giving some reduction in load space but it was very much better than the first attempt. Several vehicles were built which were put into service with the Postal and Telecommunication business for user evaluation.
At about this time it was decided to build an electric bus. The bus had 60 batteries providing power to a 96 kW motor which gave it a top speed of 45 mph and a range in city traffic of He said it was felt that at that time an electric vehicle based on a conversion of an existing petrol engined vehicle would never be really very satisfactory. It was therefore decided to engage in the design of a vehicle specifically for electric propulsion. He explained that a design of a new electric van has been prepared and one of the variants that was suggested was an electric taxi but in the event the van was never built. Two electric taxis were designed by Ogle Design and fitted with Lucas electric drive systems. One of the innovations of this design was the battery mounted in a single underfloor pannier. Another innovation was a transverse motor, driving, in this case, the front wheels via a double reduction chain drive.
In .public relations terms he thought the taxi an outstanding success. The costs of specially 'made body-shells which could only be made in short production runs, are totally uncompetitive. I have no doubt that a specially designed electric vehicly will one day be produced in quantity but the decision was taken not to pursue a special design for the low volume initial introduction of our technology,'" he said.
The next development, he explained, was to exploit some of the engineering innovation of the taxi in a design using many of the components of a conventional commercial vehicle bodyshell and the Bedford CFvan was chosen. Lucas has retained the double reduction chain-drive, but this time used it at the rear of the vehicle rather than for front w eel drive. The battery pack is mounted under the floor in an
easily removable pannier that aids maintenance.
In parallel with their technical development work Lucas adopted the policy that it is no good proving something in a laboratory or on a test track — it must be proven in service with operators. They have built as part of a scheme that is monitored by the GLC, 25 vehicles which are now in service with operators in London. The vehicles are running with the Army, the Police, CFGB, Post Office, Assoc ation News, Initial Services and two London Boroughs.
The experience they are getting from these trials in which the vehicles are doing a proper job of work and not merely taking part in tests, is invaluable in our development programme. The next step is a batch of 65 vehicles which will be complete by the middle of this year. The first were delivered to the MEB on 1st April.
He said Lucas is now concentrating on the 1-tonne commercial vehicle. But he acknowledged that this was only dip ping a toe to the water of the possibilities for electric vehicles.
Battery electric vehicles which rely solely on a battery for their source of power have a relatively restricted range. The vans they have produced have a range of between 40 miles, if they are used on a gruelling test route of 3 stops per mile, full acceleration and full braking on a very hilly circuit, to well over 100 miles if they are driven relatively gently on a flat road. Lucas have delivered vehicles to London from Birmingham driving them down the M1 "'Assuming that one of these many developments is satisfactory, we will then see electric vehicles with ranges of perhaps 200 miles but even this is inadequate for long distance motorway driving," he warned.
Plans for battery exchange stations in a motorway service area. In terms of useful energy he said a tonne of batteries is equivalent to 4 gallons of diesel fuel. This implies that a London to Glasgow coach would have to load and unload somewhere around 115 tonnes of batteries during the course of one journey which would make long distance coaches more like a freight business than a passenger operation.
The developments Lucas see of interest are those that use a battery and another source of power. "This source may be trolley wires, or alternatively it may be a small petrol or diesel engine.Lucas have been studying a hybrid car using an electric drive system for abouttown journeys and for long trips there is a small petrol engine to provide the cruise power.
Mr Kemp believes a petrol or diesel/ battery hybrid makes sense for passenger cars and for light vans that usually travel in towns and are occasionally used for inter-urban journeys. For bus operations, a different type of hy brid is required.
Studies have been done of a hybrid bus using a "Combined Battery and Trolley System" — the COMBAT bus. This is a vehicle which uses a trolley sys tem on main roads and in congested city centres or in the suburbs uses battery power.
-The great disadvantage of earlier trolley systems was the
congestion at junctions and
crossings,he said. The COMBAT bus offers the benefits of
electric traction without the cost and visual intrusion of traditional trolley systems."' In relative terms far more intensively used passenger corridors light rail and continental tramways offer the energy efficiency of rail transport without the high capital costs associated with a traditional reilway infrastruc ture. ''For low density traffic over short routes driverless or even wheelless vehicles may provide a cost-effective solution," he said.
Looking at the longer term future of transport in this country, he did not see a single uni que solution. In passenger transport internal combustion engined buses will continue to be attractive on many routes. However, the cost of their operation is likely to be considerably greater than today in real terms, he said.
"In freight the days of high mileage hgv's are numbered,"
he said, -and though for certain
aplication high-cost synthetic fuel may be used for many long haul applications increased trans-shipment to electric container trains or roll-on roll-off trains is likely to be the most cost effective solution. For short hauls in urban ares electric vehicles will be suitable but however advanced battery technology becomes there is no likelihood of battery powered hgv's being viable other than for short trips," he explained.