Full-size electric bus is a long way ofl
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Noel Millier believes the Dodge 50-Series electric could form the basis for a 50-milerange midibus SINCE the energy crisis gave a lew impetus to electric and alernative power development, 2hloride, the multi-national batery group, has been in the foref-o n t of road vehicle derelopments.
In 1973 the company estabished a Motive Power Projects 3roup. In 1975, just two years ifter the MPPG was formed, the low famous Silent Rider was Inveiled. Silent Rider is a 50eater 11-metre battery bus that vas developed in conjunction vith Greater Manchester Pasenger Transport Executive and ;ecIdon, and is basically a highierformance battery-powered >eddon RV urban bus.
Silent Rider operated about 5,000 miles in Manchester serice and appeared at many pubic demonstrations. While it
could never prove as economic in terms of fuel efficiency, range and load as a diesel-powered single or double-deck bus, it did prove that a battery-powered bus was environmentally welcome and could achieve a performance compatible with other road users.
With the original Silent Rider now destined for a place in a museum, the Chloride MPPG's efforts are clearly on the lighter urban delivery vehicle market where the lead acid battery requirement has less of a weight disadvantage than with the fullsize bus.
The electric power technology proved in Silent Rider, which remained in service for 21/2 years, has since been used in the Dodge Silent Karrier van project. Since 1976 71 Silent Karriers
have been built on the Dodge, and Chloride has improved the range of its batteries to give a 20-mile increase in vehicle range to 50 miles. Work is in progress to increase this range still further.
The batteries have a life of at least four years and are expensive to replace. Of the 71 Silent Karriers produced a few were passenger carrying — of these only one is a psv and is in service with Bournemouth Transport in Dorset. All these vehicles have Rootes of Maidstone bodies and are derived from the Dodge Walk Thru urban delivery vehicles.
The Silent Karriers have proved the concept and are successfully meeting the range, comfort and performance of the operator of urban delivery vehicles and the limited area where a bus meets these criteria.
With the Talbot group having now replaced the Walk-Thru with the Dodge 50-Series range, Chloride and Dodge now off( the Dodge 50-Series electric. A initial 100 Dodge 50-Serie electrics are expected to be bui at Dunstable this year and vvi be sold on purely a commerci. basis — rather than on an expi rimental basis.
Aimed primarily again at th urban distribution market, th 50-Series electric is available fr the whole of its sister interni combustion powered range an could therefore well provide th basis for a midibus operatior With its 50-mile range it woul clearly be totally unsuitable as coach but could well provide th basis for a city centre bus or dia
a-bus and is particularly suite to environmentally sensitiv operations. It could also prov suitable as a welfare or socii. services ambulance or bus.
In these days of gloom an despondency, could an operatc or local authority truly justif buying such a vehicle on th economic grounds which are ur fortunately the main considei ation today?
The Dodge 50-Series electri currently has a dc electric mote
that has been much improve,
since the Silent Rider days an should prove reliable and brim
the benefits of reduced mainten ance costs. The regenerativ, braking system means that th, standard vehicle brakes ar, never likely to wear out needin! to be used only in emergency o for the final stop.
The vehicle will be quieter am pollution free. It does not rely or its main engine for heating am instead has its own combustior heater which means its easy tr keep warm. It is definitely goint to be easy to sell on environ mental grounds.
The Chloride 420amp batterier used in the range are housed ir rubber-lined steel trays fitter with automatic distilled wate topping up equipment whid allows all batteries to be topper up from one point. For the drive the vehicle is simplicity itsel with two-pedal control and n( gears to worry about.
For the potential operator i.
3s have disadvantages too six per cent more expensive n its diesel powered sister to f. It is more expensive to run it uses about 21/2p worth of rent per mile and about eight :ice worth of battery per mile. aquires a 7cwt battery charger 'pled to a three-phase electric Ner supply to recharge it )ry night. It also has a higher aden weight and a limited igo.
ks oil prices seem likely to ninue to increase and the hnology behind the vehicle reases, the present disadvanes could be offset before the I of the current decade and :hin the life-span of vehicles at )sent being built.
he higher capital costs of the iicle could well be offset as a ;ult of work currently being Tied out at Leeds and Nottingrn Universities. A new type of ctric motor known as the riable Reluctance motor is beI developed and reports on it em encouraging. The VR )tor operates on a different nciple from that of a convennal electric motor. The rotation is induced by direct magnetic attraction between a shaped stator and a shaped rotor. As in all machines the magnetic field is produced by passing current through the appropriate windings, but in this new type of motor the direction of the magnetic field does not affect machine operation. The controller needs only to supply switched single directional voltage and is therefore less complicated than that needed to drive a normal ac motor.
The overall weights and efficiencies of the new system are already expected to better those of the best dc systems currently proposed or in use. The motor should be easy to produce and is expected to be considerably less expensive than dc motors.
The Dodge 50-Series electric is therefore a credible alternative to the more usual internal combustion powered vehicle whether it be for urban delivery work or passenger work within its size limitations. Chloride techical men Dr Brian Edwards and Mike Appleyard stress that it is a no-nonsense commercial vehicle available now.
As for the full-size bus, little progress seems to have been made. Lead acid battery technology is unlikely to match the needs of the high-capacity passenger vehicle; such batteries will never provide sufficient range and will always weigh too much. An acid battery powered double-decker would probably only be able to carry passengers on the upper deck owing to the high battery weight requirement within the 16 tons maximum gross vehicle weight.
As long as I can remember the sodium sulphur battery has been the answer, but very little seems to happen to make a fullsize electric bus with comparable assets to today's diesel buses a reality.
Chloride sees the significance of the sodium sulphur cell and has been working with the Electricity Council in Chloride Silent Power. MPPG has already two vehicles suitable for sodium sulphur batteries so while the company says little about progress maybe the full-size urban bus is on the not-too-distant horizon. A hint of future developments came when Chloride Silent Power announced a deal with giant US company General Electric to develop the sodium sulphur cell battery.
At present Chloride bus developments are only those that have been achieved on the back of the urban delivery vehicles While these developments coulc result in an improving climali and herald some innovation ir battery bus schemes, therE seems no way at present tha any type of bus will competE seriously with the current gener ation of diesel-powered buses.