Recycled plastics could pave Africa’s path to climate-resilient roads

From the newsletter

The African Development Bank (AfDB) has signed an agreement with a Japanese consortium for the deployment of recycled plastic technology in road construction and maintenance across Africa. The PET Asphalt Concrete has been under testing in Kenya since May and is set to be deployed in other African countries.

• African roads are highly climate-vulnerable owing to the use of conventional asphalt concrete which often buckles under extreme weather conditions.

• The new PET Asphalt Concrete technology offers greater resistance to heat and heavy rainfall, extending road lifespans and reducing maintenance costs. 

More details

• The agreement was signed between AfDb and Japan’s Shimizu Corporation, Kao Corporation, and The Nippon Road Company on August 21 on the sidelines of the Ninth Tokyo International Conference on African Development (TICAD9) in Yokohama, Japan. It formalises a framework for mutual cooperation, information and knowledge sharing, exploration for co-financing opportunities for sustainable development across Africa.

• Under the agreement, AfDB will facilitate coordination with governments, lead awareness-raising campaigns, support capacity building for local partners and explore financing options for deployment of the technology. On its part, the Japanese consortium will conduct demand and feasibility studies, test the application of the technology in various African contexts and assess investment opportunities for scaling up upon successful results.

• Developed by the Japanese consortium, the PET Asphalt Concrete technology, which comprises reinforced asphalt mixture with recycled PET plastic materials. The technology was selected in June 2025 through a competitive call for proposals issued by AfDB as part of its Sustainable Road Maintenance Program for Africa (SRMPA). According to the bank, the innovation “ demonstrates strong potential to enhance sustainability in Africa’s road maintenance sector, while supporting circular economy principles.” 

• The technology could revolutionise road infrastructure in Africa. Most of the roads are made from conventional asphalt concrete, a combination of bitumen binder and stone aggregates, which is sensitive to weather conditions such as heat and rainfall. As a result, the continent is projected to experience the highest road damage from climate change globally. However, unlike conventional asphalt concrete, the PET Asphalt technology is more stable and resistant to weather events due to the strong binding properties of PET.

• This is emphasised by a World Bank study on enhancing the climate resilience of roads and bridges in Africa, which notes that, as a result of extreme weather-induced pressure on infrastructure, African roads “will require increased maintenance and more frequent rehabilitation.” Adequate maintenance is identified as the most critical and efficient way to reduce the impact of a changing climate, while the absence of a proper maintenance regime significantly exacerbates damage from climatic events.

• Unlike conventional asphalt, PET Asphalt Concrete is more stable and resistant to weather events due to the strong binding properties of PET. By incorporating recycled plastic bottles into asphalt mixtures, the technology strengthens the binder, enhancing durability against high temperatures, heavy rainfall and erosive forces. Roads constructed with PET asphalt maintain structural integrity under thermal stress and water infiltration, reducing the frequency and cost of repairs. This approach not only addresses climate-induced damage but also integrates circular economy principles, turning plastic waste, a persistent environmental challenge, into a resource that extends infrastructure lifespan.

• Supporting this, a Tanzania-based study published in Frontiers in Engineering and Built Environment (2025) demonstrated that the optimal PET asphalt mixture, 30% PET, 30% sand and 40% gravel, outperformed conventional asphalt,demonstrating strength and durability that exceeds the country’s  road construction standards. 

• The technology is particularly relevant for Africa, where plastic waste is rising faster than in any other region, with projections estimating 116 million tonnes generated annually by 2060. Despite this growing volume, recycling capacity remains low, leaving much of the waste in landfills or incinerators. By converting plastic bottles into durable road material, PET Asphalt Concrete links waste management with climate-resilient infrastructure, creating employment in local recycling and road construction sectors while demonstrating the potential of circular economy solutions.

• However, operationalising this technology could face several challenges. Africa’s diverse climates may slow adoption, as technology transfer across regions with varying temperatures, rainfall patterns and soil conditions will require careful adaptation to local engineering standards. In addition, the initial costs of PET asphalt production and deployment are higher than conventional asphalt, creating a barrier to large-scale uptake without supportive financing mechanisms. Policy fragmentation could also limit impact, making strong alignment essential, such as enforcing single-use plastic bans and incentivising collection and recycling to ensure a reliable supply of raw materials.

• Beyond roads, the model has scaling potential for other construction and packaging industries, including cement reinforcement and modular building materials, positioning Africa to leverage circular innovations for climate-resilient, resource-efficient infrastructure at scale.

Our take

• This innovation could help address the continent’s rising plastic waste burden, which could be used as a raw material for the technology.

• With Africa currently lacking sufficient plastic recycling capacity, it could attract both domestic and foreign investment, as companies developing alternatives to conventional bitumen may source or import plastic waste for use in PET asphalt and other circular applications.

• Beyond roads, this approach could pave the way for circular innovation in other construction and packaging industries, such as cement reinforcement and modular building materials, offering Africa an opportunity to lead in climate-resilient, resource-efficient infrastructure.