Air pollution control in Bilbao, a benchmark project for Low Emission Zones (LEZ)

Thanks to the deployed network of 41 Apex AIR Pro sensors, Bilbao now obtains valuable insights about air quality in the city.


Bilbao City Council has embarked on an ambitious project to comply with the Climate Change and Energy Transition Law, which requires the implementation of a Low Emission Zone (LEZ) in municipalities with more than 50,000 inhabitants. This initiative aims to improve air quality in the city and reduce urban pollution.

To assess the impact of this initiative and ensure its success, it was essential to have a network of sensors to monitor accurately and continuously the air quality, which would complement the existing monitoring network and measure pollution levels before and after the implementation of the LEZ, and assess the impact of the measures taken in different areas.

Bilbao City Council entrusted Tecnalia and the Kunak AIR Pro air quality stations to carry out this ambitious project, which has led to it becoming Europe’s largest air quality network.


Para determinar las ubicaciones de los sensores, Tecnalia realizó un estudio previo donde se analizaron los datos históricos del tráfico de la ciudad, hizo un modelizado del mismo y creó un mapa de la contaminación urbana. De esta manera, la red desplegada se encuentra optimizada y es representativa espacialmente, obteniendo así un análisis de la calidad de aire adecuado en todo momento.

To determine the sensor locations, Tecnalia carried out a preliminary study in which it analysed the city’s historical traffic data, modelled it and created an urban pollution map. In this way, the deployed network is optimised and spatially representative, thus obtaining a suitable air quality analysis.

The preliminary study analysed all the data necessary for the correct definition of the LEZ, as established in the Directive 2008/50/EC of the European Parliament and the Guidelines for the Creation of Low Emission Zones (LEZ) prepared by Spain’s Ministry for the Ecological Transition and the Demographic Challenge, and that complies with the RD 1052/2022, of 27 December, which regulates low emission zones.

For this purpose, a network of 41 Kunak AIR Pro stations was deployed, with different configurations depending on the location, including other parameters such as external wind speed, wind direction and rainfall probes. This complete configuration provides a comprehensive view of air quality in an LEZ.

In addition, Tecnalia, together with Leber, has carried out an analysis of mobility scenarios related to the future application of the Low Emission Zone (LEZ) and its effect on air quality to select the scenario that best meets the reduction targets set by the City Council.

Bilbao City Council has taken a firm step towards a cleaner and healthier future, backed by Kunak’s leading environmental monitoring technology.

Kunak has established itself as the ideal partner for environmental monitoring and pollution control projects in cities. It offers reliable, accurate and real-time data on multiple pollutants thanks to its rapid deployment and easy-to-maintain systems.

Bilbao has therefore become a benchmark by deploying the first air quality network of its kind in a Low Emission Zone, leading the way towards a cleaner and healthier future for all its citizens.

Link to the Bilbao City Council press release


Thanks to the network of Kunak AIR Pro sensors deployed, Bilbao is now able to obtain valuable information about the city’s air quality. Data collected on urban traffic-related pollutants is integrated into the Kunak AIR Cloud platform and shared with the Bilbao City Council. This web-based software also allows the integration of external data sources such as the Basque Country’s network of air quality stations, which makes it possible to visualise and analyse all the information on a single platform and be able to make better-informed decisions.

Thanks to this information, the council will be able to analyse air quality and levels of different pollutants in each district, allowing them to make informed decisions to improve the city’s air quality by redistributing traffic or implementing new, more sustainable forms of transport. This will ultimately enable them to create a greener and cleaner city, and therefore, protect the health of citizens, thereby reducing associated health costs.

The Bilbao Low Emission Zone has thus become a role model to follow in the fight against urban pollution.


  • Pollution reduction: The implementation of the LEZ, supported by information from the Kunak AIR Pro sensor network, has enabled effective measures to be taken to reduce traffic pollution, therefore improving air quality in Bilbao.
  • Increased control and monitoring: Thanks to continuous monitoring, the City Council can track air quality in each district in detail and evaluate the effectiveness of the measures taken, thus ensuring informed decision-making.
  • A more sustainable city: The information collected allows the City Council to redesign traffic flows and promote more sustainable forms of transport, contributing to the creation of a greener, cleaner city.
  • Protecting citizens’ health: Improving air quality directly benefits the health of Bilbao and the surrounding area’s inhabitants, reducing the risks associated with pollution.
  • Compliance with European regulations: This project complies with European guidelines on air quality and the creation of low-emission zones, ensuring compliance with current legislation.
  • Future predictions: The project also includes the development of traffic-based urban pollution forecasts for the year 2030, providing a long-term vision for planning and decision-making.