Every Smartphone today has the same minimum set of sensors: Camera, Microphone, Magnetometer, GPS, Accelerometer&Gyrocscope (Games), Proximity (Calls) and a radio capable of receiving on a multitude of radio bands.
The huge number of apps that make use of these sensors will makes it impossible for any device manufacturer to not support this set of sensors. At the same time the cost of all of these sensors has dropped significantly due to the volume of devices sold. This has established a quasi standard for the set of sensors used in a smartphone.
Which sensors will make up the default set of sensors in and around a street light in e.g. 2030 when a similar convergence has happened in this market? Which applications will be most relevant in the next 20 years in cities? Which sensors are cheap enough now to put them right away into a street light or pole to later enable them via software?
What I have seen in my cursory research are these applications driving the platform (sorted by how close I personally think they are to becoming mainstream):
Dimming light based on ambient light and cars/people presence
Predictive Maintenance of the light system and the light pole sensor network itself
Anonymised observation of all types of traffic (foot, bike, car, trucks) for short- and long-term traffic optimization
Anonymised measurement of foot traffic for
retail marketing optimization
Detection of available parking spots to optimize traffic
Measurement of street-level climate to address short- and long-term air pollution issues
Note 1: The same question could be asked for the Smart Meeting Room or the Smart Office and for many other areas where it is likely that the person or the location or the vehicle will have a convergence device with it.
Note 2: Why not have an individual sensor for each measurement? Firstly having 3 sensors does not give you only 3 applications – the number of applications goes up exponentially with the number of sensors if you have some local processing power. Secondly there is (still) some overhead in managing devices and providing power and connectivity to the device. Hence per room or per person there will be one gateway device that caries most of the sensors and the connectivity.