Three years ago, Terry Hope was working as an engineer on a Canadian schooner.
He wanted to take along an electric scooter, but was told by the captain that he couldn’t bring aboard anything that couldn’t fit in a suitcase. His response, naturally, was to set about designing an electric scooter that could fit inside a suitcase. Flash forward to 2011, and his home-built solar-electric Kinetic Photovoltaic Vehicle (KPV) is on the road.
Terry started with a stock steel scooter frame, and augmented it with a variety of hand-made and off-the-shelf parts.
In its current incarnation, the KPV has a 396 W-h/24-volt battery, 28 W-h/12-volt booster battery, 10.8-volt ultracapacitor bank and a 12-volt kinetic generator.
The batteries can be fully charged from mains power within 15 to 45 minutes, and the scooter can travel around 13 miles (21 km) per charge.
Power can also be supplemented by the scooter’s 50-watt solar array. This takes the form of 14 monocrystalline cells contained within five panels mounted on the front of the bike, which are intended to serve as an aerodynamic fairing. Using rocker switches, the rider can direct power from the array into either of the batteries, or the capacitors.
The KPV weighs 44 pounds (20 kg), which makes it a bit heftier than another portable last mile transport solution we covered recently – the YikeBike. The solar array adds another 6 pounds (2.7 kg) when attached. Its top speed is 20 mph (32 km/h).
The kinetic generator consists of a sprocket mounted on the non-motor side of the rear wheel, which is linked to five gears that rotate a set of small 3-phase alternators. These alternators convert alternating current to direct current with a claimed 74 percent efficiency, and store the electricity in the capacitors. A booster switch gives the rider access to these power reserves.