Sensing the humble street light’s potential
By David Schout
Some CBD streetlights are now mini air-monitoring stations.
A new project from the Environmental Protection Authority (EPA) has turned the unassuming lamppost into something more than just street illuminators.
In 2016 the EPA, alongside distributor CitiPower, affixed small air quality sensors – about the size of a matchbox – atop street lamps on Queens Bridge as part of a trial.
The sensors collected data on the presence of PM2.5 particles – a pollutant in smoke, fine dust and vehicle exhaust emissions.
These particles are particularly small (with a diameter of less than 3 per cent of the diameter of a human hair) and light, which causes them to stay in the air for longer to be inhaled by humans and animals, and their presence is used to measure air quality.
After initial tests, the EPA was pleasantly surprised with what it saw.
“Initial results showed the construction of these sensors was quite robust,” spokesman John Rees said.
“The data they collected on the presence of PM2.5, typically from vehicle emissions, was monitored and analysed and the trial demonstrated low-cost sensor technology can be usefully applied.”
The success led to the deployment of more sensors throughout the CBD.
“Several small operational sensor networks are now in place,” Mr Rees said.
Early in the trial, measurements recorded from the small sensors were consistent with the EPA’s nearest permanent monitoring station in Footscray. This suggested they could be onto something.
The trial’s success showed the EPA that it can incorporate new technologies into existing air-monitoring infrastructure, which could be a catalyst for more sensors throughout Victoria, especially remote regions.
The sensors cost about $200, which makes them a desirable, compact technology at a fraction of the cost of larger stations.
Also, they work by transmitting air quality data via secure radio communication, which is relatively immune to telecommunication outages that can interrupt data flow in traditional monitoring networks.
“While sensors are not considered Australian Standards methods, they can provide useful information on the status of air quality for particulate matter and gases,” Mr Rees said.
“The very low costs for purchase and operation make them attractive in a wide range of applications and EPA is developing potential projects that could use them.”
The robust nature of the sensors mean they have withstood adverse weather conditions, including strong wind and rain.
The trial has shown that one platform – in this case, a street light – can support multiple applications in the EPA’s bid for a more sustainable city.