These fall into three categories – Mini compact vehicles, two wheel vehicles and mobility scooters.
Mini compact vehicles can fit three to the space taken by two full size cars for curbside parking. They can be incorporated into parking structures at a higher density since they are shorter (less than 14 feet) and narrower (less than six feet). The actual density would depend on the layout of a mini-compact parking space including the clearance needed for entering and leaving the space. Generally speaking this should approach or exceed the thirty percent improvement experienced with curbside parking.
Cars – including cars like a Mini Cooper, Miata, Audi TT, BMW Z4, Honda Insight, Honda S2000, VW GTI, VW Beetle and many others
Neighborhood Electric Vehicles like the GEM
Compact Utility Vehicles – meter reader and ground maintenance/delivery styles like the Dymac
Three-wheel enclosed motorcycles like the ZAP Car
These include bicycles, electric bicycles, Segways, mopeds, motor scooters and motorcycles.
These all increase the parking density by multiple factors. The numbers of these that can fit into one car space are approximately as follows:
Ø Bicycles – up to 15 in one car space
Ø Mopeds – up to 10 in one car space
Ø Motor Scooter – up to 7 in one car space
Ø Motor Cycles – up to 7 in one car space
In addition these can be parked in spaces not suitable to cars. These include islands in parking lots and next to buildings in areas not usable for car parking or pedestrians. Bicycles, mopeds and Segways can be parked on sidewalks in the parking meter area provided suitable security and clearance from the meters is available.
Motorcycles and motor scooters can share curbside parking spaces with smaller vehicles to instantly double the parking spaces.
Long term parking (more than 20 minutes) for bicycles, Segways and mopeds requires that better security measures be provided than a place to lock onto. Parking attendant oversight is one option and various other options like lockers can be used successfully. Lockers and related techniques will reduce the density of parking specified above and still result in huge space and cost savings per vehicle compared to cars.
All the two wheel vehicles have the additional advantage of being lightweight. This means that the parking surface only needs to conform to weight bearing specifications for pedestrian traffic not for truck traffic. This has potential to reduce parking costs drastically.
These are good options for people with limited ability to operate larger vehicles. They allow mobility for groups including physically challenged senior citizens that would otherwise have trouble getting around. These can be parked in front of businesses with only the need for a place to lock onto. They can enter most buildings thanks to wheelchair access requirements. They are viable for short trips of one or two miles. Some have used them for even longer distance travel. This means trips with virtually no parking requirements and almost zero congestion impact.