Continuing our review of Matt Darst’s study of space efficiency and meters, there is also a lot of really valuable analysis of the different types of parking space meters.

 This discussion covers three types of meters: Pay by Plate, Pay and Display, and Pay by Space meters. (Additional meter types exist, such as single space meters, parking garage ticket dispensers, and pay by phone zones with no physical meter present). Pay by Plate Meters are meter terminals where individuals enter their license plate into a meter terminal and pay for time. Pay by Space meters work similar to Pay by Plate, except motorists enter a number painted on their parking space into a meter instead of their license plate number. Pay and Display meters are meter terminals where drivers pay for a period of time, print out a ticket for proof, and then go back to their car and leave the ticket on their dashboard.

 Pay by Plate and Pay by Space have the advantages of not needing to return to the car once the meter has been paid. Additionally, Pay and Display meters have the occasional paper jam, and need to have paper and ink refills. However, Pay and Display meters have the advantage of not giving motorists the opportunity to forget a number, whether that number is their license plate or their parking space number. People entering the wrong number and getting a citation creates legitimacy problems that undermines the meter system.

 Of these three types of meters, Pay by Space meters are the only type that require demarcated spaces, since each space needs to be defined discretely and numbered for the meter to function. Because Pay by Space meters track payment by space rather than by actual car, drivers who leave early are subsidizing the next driver, who may park for a short period of time, notice the available time, and not pay at all. A remedy that can maximize revenue is to have smart parking sensors (like those provided by Streetline) attached to a smart pay by space meter. Whenever a parking space is vacated, a highly accurate smart parking deployment can void the remaining time on that space, so the next driver pays for their own fair, maximizing needed revenue for cities.