Piaggio introduces parallel hybrid Vespa – May 15, 2006
May 15, 2006
Filed under Features
Like Honda, Toyota, Ford, General Motors and a growing number of other automobile manufacturers, Italian powersports and small car manufacturer Piaggio has unveiled two hybrid vehicles designed to improve gas mileage and reduce impact on the environment.
Based on the standard Vespa LX 50 and X8 125 scooters, the HyS prototypes are “parallel hybrids,” meaning a combustion engine and a zero-emissions electric motor are mechanically and electronically linked and simultaneously supply power to the wheel. Piaggio says the linked gas/electric engine can provide a 20 percent reduction in fuel consumption compared to a normal four-stroke of equal displacement.
While powersports enthusiasts often point to two distinct shortcomings in zero-emissions technology — a lack of speed and range — parallel bybrids are designed to leverage both gas and electricity in an effort to optimize power and distance.
During strong acceleration and when maximum power is required, parallel hybrid technology simultaneously uses the internal combustion engine and electric-drive motor for increased performance. When the electric-drive motor supplements the gasoline engine, it provides higher torque, which in turn results in smoother acceleration.
The Vespa rider uses all the normal controls as well as a specific switch to choose one of four operating modes: standard hybrid, high-charge hybrid, low-charge hybrid and electric-only.
In the first three modes, the HyS manages power from both engines using a drive-by-wire type system — the electronic management system interprets the rider’s request for more torque and selects the assist ratio based on the state of the system (e.g. the level of battery charge). During deceleration and braking, the control system recovers and recharges the battery.
In standard hybrid mode, the battery charge is maintained at optimal 75 percent traction levels; the high-charge hybrid function is geared to maximize the range of the electric motor at 95 percent; and the low-charge hybrid mode obtains maximum performance with minimum consumption at 20 percent.
In electric-only mode, the Piaggio HyS shuts down the combustion engine and turns into a silent, zero-emission electric vehicle. In this mode, the Vespa LX 50’s electric motor offers maximum output of only 1 kW. Maximum range is only 20 kilometers (12.4 miles) at a maximum speed of 25 km/h (15.5 mph). The 2.5 kW (3.4 hp) produced by the X8 125’s electric motor also only offers a range of 20 kilometers (12.4 miles), but at a similarly slow speed of 35 km/h (21.7 mph).
Piaggio says complete charging from a 220V wall socket takes about three hours, but the batteries also charge by capturing kinetic energy via regenerative braking.
The technology is neatly tucked away and the two Piaggio HyS units look like any other Vespa. The traction batteries are hidden in the under-seat storage space, which is sufficiently large on the X8 125 HyS to also hold a helmet. The Vespa LX 50 HyS hybrid prototype comes with a top case to make up for loss of under-seat storage.
Other cues to HyS heritage are a battery charge indicator on the dashboard as well as a recovery indicator to display any problems.
While Piaggio also reportedly is working on a hybrid diesel-electric Granturismo scooter designed to reach 136 mpg, the Italian manufacturer is not the only powersports company to explore alternative-fuel two-wheelers.
Honda has spent quite a few R&D yen on prototype zero-emissions two-wheelers, and Aprilia did some testing with hydrogen fuel cells even before the Piaggio takeover.
Yamaha’s Passol lithium ion-powered electric scooter went on sale in Japan in May 2003, and the Japanese manufacturer more recently introduced parallel hybrid and methanol-powered prototypes at the Tokyo Motor Show in October.
Developed as a short-range vehicle for urban use, the Passol produces 60 percent less CO2, 90 percent less NOX, and 80 percent less SOX than a 50cc Yamaha gasoline engine. The HV-01 parallel hybrid has a brushless DC motor mated to a gasoline engine, and the methanol-powered FC-me is powered by the Yamaha Direct Methanol Fuel Cell System, which uses a liquid methanol-water solution.
Yamaha’s hybrids remain prototypes, for now, and Piaggio hasn’t revealed whether it plans to bring its HyS scooters to market.