Optare, the British manufacturing company that is pioneering the introduction of fully integral low-floor battery-powered buses in the UK and Europe, will be providing visitors to LCV2013 with the opportunity to experience one of its award-winning electric vehicles.
A 9.25 metre Optare Solo EV with seating for 31 and a total passenger capacity of 45 with standees, will be taking visitors on circuits of the test track at the Millbrook Proving Ground in Bedfordshire.
To book their EV experience, visitors to the two-day event, which is organised by Cenex, the Centre of Excellence for low carbon and fuel cell technologies, can simply go to the Optare stand SP-09 in the outdoor display area.
Along with the company’s larger Versa EV model, the Solo EV is already carving out a niche for this type of vehicle with buses in service in Durham, Nottingham, Coventry, Poundbury in Dorset, and at Heathrow Airport. Positive trials have taken place in many parts of the UK resulting in significant orders throughout the country and Optare is about to deliver the first full-size battery-powered bus to enter service in Scotland. Exports have also commenced with a recent delivery to Switzerland and an order in the pipeline for Holland due to be fulfilled by mid December.
Both the Solo and Versa EV models are powered by a Magtec P144 electric motor delivering 150kW of power and 2380 Nm of torque at 2650 rpm, giving them swift and smooth acceleration and excellent hill climbing capabilities, as proven in service. A maximum speed of 95 kph (59 mph) can be comfortably achieved to ensure inconspicuous traffic compatibility.
The Magtec motor derives its energy from 52 lithium iron magnesium phosphate batteries of 12.8 volt/138 Ah (Rev 2) capacity. These maintenance free batteries provide a total of 333 volts DC nominal x 2 in parallel. They are arranged in two equal packs of 26 batteries that are located each side of the engine compartment at the rear of the bus, in the same space as occupied by the powertrain of a conventional diesel-engined Optare bus.
This driveline provides the Optare Solo EV with a forecast daily range of approximately 110 to 150 km on a single charge dependent on the duty cycle. This can, however, be significantly increased through the use of fast-charging technology on the bus, linked to charging points at the depot or at suitable points on the route, such as bus termini.
Normal charging is by means of two 7.5 kW integrated on-board chargers connected to a standard commercial three phase supply and which enables a full charge from zero, to be achieved in approximately six hours. The optional 50kW off-board charger is an alternative to provide fast-charging in around two hours, or opportunity charging as required. An induction charging system option will be introduced later this year.
The drive motors, summation gearbox, chargers and battery packs are contained within a demountable frame, which enables rapid removal and uses ‘no loss’ couplings for fluid lines.
In line with the entire Optare bus range, the Solo EV features the EcoDrive™ driver’s instrument panel as standard. This has a large TFT screen which provides the driver with direct feedback on his or her driving behaviour, monitoring acceleration, deceleration, cornering, and fuel economy, and also delivers a ‘driver’s skill’ score. The display also shows the battery charge level together with all normal vehicle functions.
In structural respects the Solo EV is the same as a standard diesel-engined equivalent. It features all welded heavy-duty box section integral construction using a combination of stainless and high-grade carbon steel, backed up with an anti-rust protection system to ensure a long life. A combination of GFRP and aluminium modular exterior panels keep weight low and facilitates easier, cost effective repair or replacement.
Passenger ride comfort is assured by full air suspension with a ‘kneeling’ capability on the front axle that reduces the entrance step height from 265mm (10.5 inches) to just 200mm (8.0 inches) when the air bags are exhausted. A manual fold-out ramp makes access easier and safer for passengers with reduced mobility, in wheelchairs or with baby buggies.
At its showcase assembly plant in Yorkshire, Optare produces a range of vehicles that have positioned it as the pre-eminent manufacturer of low carbon vehicles in the UK. These range from conventional diesel-powered models, which deliver class-leading fuel efficiency as a result of their low weight and optimised driveline matching, through to alternative fuelled vehicles, diesel-electric hybrid vehicles and full electric buses.
Providing an interesting comparison with the Solo EV at LCV 13 is an equivalent diesel-powered Solo SR model, which will be on static display. This 9.0 metre bus can carry up to 29 passengers seated on Esteban Civic V3 seats and up to 21 standees. Power is from the Mercedes-Benz OM904LA diesel engine, renowned for its fuel efficiency and which is matched to an Allison 2100 Series five-speed automatic gearbox.