A project to mount air quality sensors on Transport for London’s (TFL) hire bikes has been awarded seed money at the hackathon held at Climathon. The data will be used to provide more granular and more informative air quality maps for the city. The event was organised by the EU-funded climate innovation network Climate-KIC.

AirPublic proposes to put sensors on London’s rental bikes so as to fill in the gaps in the officially run air quality sensor networks. 

Mobile device management tablet

It’s no secret that the air quality in London, as in many other big cities, is awful. There is increasing awareness of the impact of this on public health and the economy.  The air in the UK’s biggest cities breaches EU legal limits, and it’s not going to get better any time soon. 

London’s air quality monitoring depends on a small network of sensors which is used to test for compliance against air quality standards. There are only 120 sites, measuring oxides of nitrogen (NOx), sulphur dioxide (SO2), ozone (O3), carbon monoxide (CO) and particles (PM10, PM2.5). These sites provide hourly information which is then posted via web and other platforms. These monitoring stations are run by the Environmental Research Group at King’s College. This has its own app which provides air quality information, and regularly updated maps; but most of what the map shows is derived from models, based on the data from the 120 sites. 

The AirPublic project argues that this modelling is not all that reliable. For example,it says that a community monitoring initiative supported by the London Sustainability Exchange demonstrated that the pollution levels in some locations were actually worse than those predicted by the model. The model doesn’t account for the ‘canyon effect’ which helps to make air quality in Oxford Street arguably the worst in the whole world, for example.

Mounting sensors on bikes would increase the number of sampling points. A pilot roll-out on 50 hire bikes would cover 2,500 out of London’s 2,500km of main roads every day. By measuring pollutant levels 10 seconds (around every 20 metres) they could generate an estimated 1.3 million data points from different locations every day. The bike sensors would be cheaper, less accurate sensors than the heavy-duty ones in the London Air Quality Network’s stations, but there would be a lot more of them. A cunning feature of the AirPublic proposal is that they could calibrate themselves against the more accurate monitors every time one of the bikes pass by one of the official sensor sites, improving the overall quality of the data.

Other good ideas include allowing users of individual bikes to track their own pollution exposure in real-time and presenting users of TFL’s bike route planning tool with ‘clean’ and ‘dirty’ options as well as ‘busy’ and ‘quiet’ choices.

AirPublic is still just an idea, albeit a well-defined one judged worthy of funding. It’s not yet certain whether it’s going to be a start-up, a community benefit company, or something else - although it will have to resolve this in order to receive its seed money. 

The first step will be a technical proof of concept, due at the Sustainable Innovation Forum scheduled to precede the global climate talks in Paris this December. The sensor hardware is not yet built, though open source Internet of Things start-up Opensensors.io has offered to host the data and provide analytics for free, and there has been some discussion with OpenTRV about using its Lora-based IoT network to provide connectivity for the sensors.

After the proof of concept demonstration there will probably be a pilot involving some 50 bikes in London, followed by a full roll-out with 500 bikes. It may then be rolled out to bikes in other urban hire schemes.