Public lighting sensor network

Introduction

Introduction

The pilot phase of the City of Prague Public Lighting Sensory Network project saw the installation of new tops to  92 smart LED streetlights near Karlínské náměstí in Prague 8. Some of these lights have sensors for measuring and collecting data on noise, dust and other pollutants, or which can be used do determine the density of people in the area. The data is then sent to a data platform, which not only stores all this data in one place, but also allows the lighting intensity of the indivisual streetlights to be contrlled and set.

In general, the Czech Hydrometeorological Institute (ČHMÚ) is the certified authority  for measuring air quality, and it measures conditions all across the city (macro level). The purpose of the project to install sensors in the public lighting network in Karlín is partly to provide inhabitants of Karlín and the brought with detailed information, and also to test the potential for measuring and comparing the results for twoo streets  next to one another, for instance, and then, based on those measurements, decide whether to plant trees or adopt other measures in specific places.

Below we also present a comparison with data from Czech Hydrometeorological Institute, which shows that the data trend is similar, although in some cases the data may be either undrevaluated or overvaluated, caused by the location of the sensors, for example.

Functions

  • Online remote control or each light
  • Lighting controlled on a policy basis
  • Collection of a sensory data and adta on air pollution
  • Municipal Wi-Fi network for connecting to Internet

Benefit

  • Automatic notification  of faults in public lighting
  • Online publicy available information about the results of environmental measurements

Map

The individual circles on the map represent sensors fitted on lights, where the size of the circle determines the average level of pollution for the selected period. After choosing an individual pollutant in the right-hand corner of the visualization we see the partial values for the selected period.

In general the pollutant values are lower in Kollárova street, apart from the SOconcentration, whoch is higher on average.

 

Comparison of measurements

The section below gives a comparison of certain measurements from sensors situated on lamp posts in relation to another variable.

Comparison of PM10 (dust particle) concentration

For a comparison of PM10 concentrations measured on the lights in Karlin with the option to select the ČHMÚ station, see (link): http://portal.chmi.cz/files/portal/docs/uoco/web_generator/aqindex_slide1/mp_AKALA_CZ.html

Comparison of NO2 concentrations during the day

The graph below shows the average NO2 values measured around Karlínské náměstí and the ČHMÚ station, which is situated near the river. When testing we determined the differences in the values measured by the light sensors and those from the nearest ČHMÚ station. The diffrence in the values could be caused by the ocation of the ČHMÚ station, the height at which the measurement equipment is installed nad/or by environmental factors, as the nearest ČHMÚstation is situated close to the river, where there is greater air flow. In both cases pollutants concentrations  fall as the hour gets later, when the overall amount of traffic is reduced.

Comparison of NO2 concentrations in relation to days in the week

Here we find pollutant data from the smart lights around Karlínské náměstí, showing pollution on the individual days of the week in comparison with the ČHMÚ measurement stations. On the right it is possible to select a certain ČHMÚ station and compare that selection with the locality in Karlín.

Data from individual sensors 

The visualization shows the average values for all lamos fitted with the given sensor that measures the selected pollutant. Selecting a specific light , see bottom right on the map, enables a particular sensor to be drawn on the light.

Use and interpretation of data

Data such as dust combined with temperature can be used to plan the routes of sprinkler trucks, particularly in order to reduce dust and ground-level ozone intenzity. Other data sets currently being prepared for publication, relating to density of people, for example, may be used by the municipality for planning individual repairs and closures of the roads in question.

List of public lighting sensors

These sensors are at a height of approximately 4.5metres above the ground.

Requirement Produkt Měřené hodnoty Vyčítací frekvence
Dust Vaisala AQT420 PM2,5 and PM10, sampling time 60s, sampling interval 10 minutes, range for PM2,5: 0 – 2000 mikrogams/m3, range for PM10: 0  - 5000 µg/m3, accurancy 0,1 µg/m3 15 min. from the gateway to the platform, reading more frequent at gateway
Ozone Vaisala AQT420 or AQT410* Range 2000 ppb, detection limit 5 ppb, measurement accurancy ± 60 ppb in typical outdoor environment 15 min. from the gateway to the platform, reading more frequent at gateway
SO2 Vaisala AQT420 or AQT410* Range 2000 ppb, detection limit 5 ppb, measurement accurancy ± 50 ppb in typical outdoor environment 15 min. from the gateway to the platform, reading more frequent at gateway
CO Vaisala AQT410 or AQT410 and AQT420 Range 10000 ppb, detection limit 10 ppb, measurement accurancy ± 200 ppb in typical outdoor environment 15 min. from the gateway to the platform, reading more frequent at gateway
NO2 Vaisala AQT410 or AQT420* Rozsah 2000 ppb, detection limit 5 ppb, measurement accurancy ± 25 ppb in typical outdoor environment 15 min. from the gateway to the platform, reading more frequent at gateway

A description of the individual pollutants can be found in the Programme for the Improvement of Air Quality in the Prague Agglomeration - CZ01 https://www.mzp.cz/cz/zlepsovani_kvality_ovzdusi_praha_2016

Data resources

Pilot project in Karlín

Historie a aktuální data polutantů ze senzorů Karlínských lamp

Datová sada obsahuje odečty z 43 senzorů, které jsou rozmístěny na vybraných lampách.


Datové soubory
Name Format
Naměřené hodnoty polutantů v ovzduší 2. pol. 2018 zip:csv STÁHNOUT
Naměřené hodnoty polutantů v ovzduší 1. pol. 2019 zip:csv STÁHNOUT
Naměřené hodnoty polutantů v ovzduší 2. pol. 2019 GZIP STÁHNOUT
Cataloging entry
Label Value
Periodicita aktualizace denně
test test
Dokumentace DOCUMENTATION
Licence Creative Commons CCZero
Poskytovatel dat Operátor ICT a. s.
Odkaz do katalogu http://opendata.praha.eu/dataset/lampy_karlin_znecisteni