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Air-purifying billboard

The air-purifying billboard is a Macedonian innovative prototype that aim to clean the ambient air mainly polluted from traffic. There are currently 2 pilot billboards implementing this technology.
The vacuum cleaning based solution, if set to all 820 billboards in Skopje can reduce air pollution by up to 20%, as the filter can purify 2.5 million cubic meters of air per month. The filters can absorb the PM10, PM 2.5 and other harmful particles. Around 200,000 bus passengers and 150,000 more pedestrians will directly benefit from this innovation every day.

Innovation Summary

Innovation Overview

Air pollution poses a major environmental and health concern for Macedonia’s population of two million people, particularly for those living in the capital and all other larger cities. Per the European Environment Agency, the capital city of Skopje is among the most polluted cities in Europe. The latest Ministry of Environment report indicate that household heating practices (biomass burning) constitute 32% of total emissions. Together with traffic congestion (19%), large-scale construction works (19%) and industry (18%), these emissions have led to the highest average concentration of pollution in Skopje in history, with a record level (1219 μg/m3 hourly) of harmful PM10 particles in winter. The actions of the relevant institutions are extremely slow, and burdened by bureaucracy. The situation is highly critical in the past 5+ years, yet, no action has so far been undertaken. The costs from the air pollution are very high, both for the state, but more importantly for the citizens. As usual, the burden is carried most heavily by the most vulnerable, poorest citizens.
The idea for an air-purifying billboard was the fruit of a Climate Challenge for citizens, which was designed to find innovative solutions to the most pressing urban challenges. The idea was developed into solution at a weekend social innovation camp. Two prototype billboards are already constructed by a local company and currently being placed at two very frequent crossroads in Skopje. The billboards will aim to clean the air mainly polluted from traffic congestions. As the personal exposure to air pollution showed, the citizens that walk or cycle are mostly exposed to the pollution, and particularly to the pollution caused by traffic congestions, because it remains at the height of the people while walking or cycling on the streets.
While the strategies to reduce the congestions, and decrease the number of highly polluting vehicles are not efficient, it is critical to develop such cutting-edge innovations that can achieve quick wins. The solution, if set to all 820 billboards currently placed at the whole territory of the city can reduce air pollution by up to 20%, as the filter can purify 2.5 million cubic meters of air per month. The filters can absorb the PM10, PM 2.5 and other harmful particles. The solution is rather simple, based on vacuum cleaner process of working, with several types of filters installed with proper devices to suck the air and let it out after cleaning. The two prototype billboards will be used to test in detail all the possibilities and specifications before the project can be replicated on a large scale.
Around 200,000 bus passengers daily and at least 150,000 more pedestrians will directly benefit from this innovation every day, and the rest of Skopje residents indirectly while driving, or those living very near to the congested streets. If the prototype is successful, City of Skopje will add this feature to all existing billboards.

Innovation Description

What Makes Your Project Innovative?

There is nothing happening in Macedonia to clean the air, or to sustainably address the problem with systematic solutions. This billboard and some other small isolated civil society driven actions are expected to trigger the reaction of the institutions to stimulate similar citizens initiated and driven innovations. Despite its simple design and easy installation and functioning, this type of air purifying billboard is unique and different, and it will be the first time to test such a solution. At the second stage of prototype testing, the team will add air quality sensors and develop IoT solution for data analytics and predictions. The air purifying billboard is currently being patented (there was no other such solution found globally, while there are other that work on different technologies). If the prototype is successful, it will be commercialized and produced and sold internationally.

What is the current status of your innovation?

The two prototype air purifying billboards are, as we write this application, being placed at two congested crossroads in the City of Skopje. The deployment of the solution has been delayed for a year, and instead of installing them last September, they are being installed now. The challenges and reasons for delay were multiple, and will be described later in the application.
The story started in 2016, with the citizens Climate challenge where citizens were invited to compete with their innovative ideas in solving 4 critical urban challenges in Macedonia. Out of the 68 very good quality ideas, in 2 rounds of selection, the air purifying billboard idea was among the 9 finalists. Ranked as 2nd, the air-purifying billboard triggered the interest of the City of Skopje Mayor, and got a funding to produce and test the prototype. Skopje Lab, aimed to design and test innovative public services and solutions is now leading the process of deploying and testing the solution.

Innovation Development

Collaborations & Partnerships

The innovation came from an employee of the City of Skopje who first pitched his idea within the Citizens Challenge, which was led by UNDP and USAID, in partnership with the City of Skopje. The UNDP’s partnership with the City of Skopje was critical in this case to make this innovation see the light of day. Mechanical faculty then joined in preparing the designs and drawings, which private companies owning the billboards gladly provided two billboards for no costs to test the prototypes.

Users, Stakeholders & Beneficiaries

Numerous mentors worked with the team to develop the prototype. The solution was redesigned several times until the best one was made, currently the business model of the product is being developed with another team of mentors, all of it facilitated by Skopje Lab. Citizens were able to visit the team booth at the challenge weekend camp and provide feedback. However, the greatest involvement and feedback from the citizens will be solicited in the next phase of prototype testing.

Innovation Reflections

Results, Outcomes & Impacts

The results of the innovation are yet to be seen in terms of the power of the filters and the quantity of air that can be cleaned, however all mathematical calculations indicates to great success. If successful, and scaled up and installed at all 820 billboards in Skopje, it could reduce air pollution by up to 20%, with the filter purifying 2.5M m3 of air per month.
The solution has attracted huge attention among the citizens and among the relevant authorities. This will have huge impact for all citizens and visitors in Skopje, estimated to around 1M during work week (with 650,000 estimated residents plus commuters and tourists). The investment is estimated to around $2M, which is very low compared to the impact expected to achieve and the health costs decrease.

Challenges and Failures

The roll out of the project was delayed a year, initially projected to start in 2017, which was a challenge.

Another challenge was to identify the best possible locations, near to one of the air quality monitoring stations – that will enable to measure the results of the billboards and near to congested crossroad as most polluted spots. This has been resolved and the two locations are identified.

However, there was a challenge that resulted in a significant delay of deployment of the prototypes. Political turbulences and change in power in the local government caused significant delay in obtaining the approvals due to additional project and design reviews. Again, this was resolved and the billboards are now being deployed, but one whole year was lost.

Still the team behind the solution did not give up and the innovation will be tested.

Conditions for Success

In our case, the most important success factor is the motivation and personal values, while the critical precondition was the financial resources and supporting infrastructure. The support of the municipal authorities was the break-through point.


Testing and prototyping of citizens’ ideas have indeed proven potential for replication to all government problems, which is actually the main purpose of Skopje Lab and other public service innovation labs. As for the solution itself, if successful it will be replicated in Skopje and then produced commercially.

Lessons Learned

- Be persistent and fight for the idea, especially if you are working in countries where innovation is not high on the agenda of government officials. Macedonia is country with very limited opportunities for ideas generation, especially for citizens and individuals, and it counted on the partnerships with the UNDP to execute the innovation.
- Believe in the innovation, even when others doubt it (there are still very simple things that no one else has yet thought of, and this can be an idea of your friend, colleague or neighbor.)
- Provide thorough support to the team in all possible areas of prototype development.
- Iterate, as many time as it is needed, but do not overdo it, as you might lose the momentum of interest.

Year: 2018
Level of Government: Local government


  • Implementation - making the innovation happen
Call for Innovations Call for Innovations
This case was submitted as part of the Call for Innovations, an annual partnership initiative between OPSI and the UAE Mohammed Bin Rashid Center for Government Innovation (MBRCGI)

Innovation provided by:

Date Published:

17 October 2018

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