Electric vehicles larger than cars include many boats, trucks, buses and other industrial and commercial vehicles, manned and unmanned aircraft and military vehicles for the field of combat and supply lines, even tugs for aircraft. Some electric vehicles are the size of a car but pack a much bigger punch. For example, forklifts and earthmovers can have much more powerful motors with many times the kW and Nm torque of car motors. Autonomous Underwater Vehicles AUVs incorporate batteries at up to 400kWh, the storage capacity of up to ten cars. All these vehicles account for over 60% of the money spent on electric vehicles today and it is there that much innovation is happening first, long before the car industry gets involved.
For example, Scheuerle a subsidiary of KAMAG has long used large flywheels to store the braking energy of massive load transporters and now it is applying it to large electric on-road vehicles. They may beat Volvo into the marketplace which is trialling small Kinetic Energy Recovery Systems KERS in a car. The Scheuerle system is shown below.
Scheuerle KERS for trucks and buses showing flywheel left and complete unit right
Source IDTechEx
The Dutch, such as eTraction, are particularly active with in-wheel and near-wheel motors for buses, trucks and other large electric vehicles and it is possible that such components will be profitable for these applications before cars. Integrated into the rear axle of buses, they meet international city bus specifications. Normal disc brakes and suspension connect to the customised rear axle. They are seen in the HyTruck and Hybricon projects and others. Examples are shown below.
eMotion in-wheel and near-wheel motor
Source eMotion
eMotion in-wheel and near-wheel system for large vehicles
Source eMotion
A heavy duty near-wheel motor left and eMotion in-wheel motor for large vehicles on right
Source IDTechEx
Early on, hybrid forklifts were launched by Mitsubishi Heavy Industries and others. (Mitsubishi Motors does the small commercial vehicles and cars). It was on forklifts that asynchronous motors were first widely used several years ago. Now, this year, we see them in about ten new cars as MES and others come down market, though it must be said that AC Propulsion had them in cars very early and Tesla has used them in its very successful Roadster car. Supercapacitors have been on buses for a decade yet they are not yet designed into volume cars.
The use of gas turbines - jet engines - in buses dates back 12 years to when DesignLine put Capstone Turbines ones in hybrid buses that used lead acid batteries and such buses have sold in thousands since then, now with lithium batteries of course. They will only appear in cars when the totally redesigned mini versions by Bladon Jets are fully proven on the Jaguar supercar, we guess in about three years. Fuel cells are in limited use in large military vehicles as range extenders and there have been more trials of them on buses than cars over the last twenty years, which tells you something. It is not yet clear what the sweet spot for another range extender, the Clarian Labs rotary fuel generator will be but we do know that overcoming the limitations of batteries will involve both advanced range extenders and energy harvesting. Although harvesting by regenerative braking is now commonplace in cars and larger vehicles and solar photovoltaic roofing is commonly available on both, the energy harvesting shock absorbers that can produce particularly continuous and substantial power are being launched in military, commercial and industrial vehicles before cars, where the business case is, as yet, more debateable. Watch Levant Power and others.
For more attend Electric Vehicles Land Sea Air USA 2012,where a large number of electric vehicle manufacturers not seen in conventional EV events will present including WheelTug aircraft electrification, MotoVolta, LLC motorbikes, SolTrac farm tractors, Monterey Bay Aquarium Research Institute Autonomous Underwater Vehicles AUVs and manufacturers of industrial, commercial, military, e-bike, cars and other EVs.