By Leo Mirani, September 13, 2014

Installing a parking sensor on London's Savile Row.
This week, the City of
Westminster, one of London’s local councils, will start embedding the
first of 3,000 sensors into the streets. They
will be in the ground by the end of March, making London the world's
first major city to adopt the long-heralded "smart parking" revolution.
The idea is simple. According to the council, motorists spend an
average of 15 minutes searching for a space in Westminster—which with
Parliament, the main shopping district, and dozens of tourist sites, has
a legitimate claim to be the heart of London. If drivers know where the
empty spaces are, they won’t have to cruise the streets looking for
one.
Other cities, most famously San Francisco, have experimented with "smart parking" and companies from France to America are developing the technology. But San Francisco turned off its sensors on
December 30, 2013, and is now evaluating the results of its pilot
program. Westminster is going full steam ahead, bashing in 50 sensors a
day with a team of three men. Boroughs in Manchester and Birmingham are
also trying out the system.
Each sensor in the ground detects when a car is
parked on the street above it. The council releases the data to the
public through a smartphone app. Results from a pilot program in 2012
were encouraging: The proportion of occupied parking spots that weren’t
paid for dropped from 12 percent to under 10 percent, a sign that more
people were paying for parking, says Kieran Fitsall, the parking
services development manager for the council. (Some proportion of spots
will always be unpaid for, because some vehicles are loading or
unloading, dropping people off, or have exemptions.)

The first generation of sensors protruded on the surface; the next will be flatter. (City of Westminster)
Westminster has 10,000 parking bays that
visitors can use (plus more for residents only). The first phase of the
program will see 3,000 sensors, each with a battery life of five to
seven years, installed in visitor bays in the most congested areas of
Westminster, which include Mayfair, Soho and the theater district, at
cost of £650,000 ($1.07 million). Based on the results, the council will
probably expand the program to the other 7,000 bays that visitors can
use.
The list of benefits is long: Apart from reducing traffic, fuel
consumption, and emissions from cars, it boosts the local economy as
people spend more time in shops, restaurants and offices rather than on
the street. Though the app could be used to catch drivers who’ve
overstayed their paid parking time, Fitsall says Westminster has no
intention of doing so. Nor does it plan to use the data to change
parking prices in higher-demand areas, as San Francisco did.