Authors: Diana Adela Martin (University College London), Suleman Audu and Jeremy Mantingh (Engineers Without Borders The Netherlands). 

Topic: Circular business models. 

Tool type: Teaching. 

Relevant disciplines: Chemical; Biochemical; Manufacturing. 

Keywords: Circular business models; Teaching or embedding sustainability; Plastic waste; Plastic pollution; Recycling or recycled materials; Responsible consumption; Teamwork; Interdisciplinary; AHEP; Higher education. 
Sustainability competency: Integrated problem-solving; Collaboration; Systems thinking.

AHEP mapping: This resource addresses two of the themes from the UK’s Accreditation of Higher Education Programmes fourth edition (AHEP4): The Engineer and Society (acknowledging that engineering activity can have a significant societal impact) and Engineering Practice (the practical application of engineering concepts, tools and professional skills). To map this resource to AHEP outcomes specific to a programme under these themes, access AHEP 4 here and navigate to pages 30-31 and 35-37.  

Related SDGs: SDG 4 (Quality education); SDG 11 (Sustainable cities and communities); SDG 12 (Responsible consumption and production); SDG 13 (Climate action); SDG 14 (Life below water). 
Reimagined Degree Map Intervention: More real-world complexity, Active pedagogies and mindset development, Authentic assessment, Cross-disciplinarity.

Educational level: Intermediate. 


Learning and teaching notes:   

This case study is focused on the role of engineers to address the problem of plastic waste in the context of sustainable operations and circular business solutions. It involves a team of engineers developing a start-up aiming to tackle plastic waste by converting it into infrastructure components (such as plastic bricks). As plastic waste is a global problem, the case can be customised by instructors when specifying the region in which it is set. The case incorporates several components, including stakeholder mapping, empirical surveys, risk assessment and policy-making. This case study is particularly suitable for interdisciplinary teamwork, with students from different disciplines bringing their specialised knowledge.  

The case study asks students to research the data on how much plastic is produced and policies for the disposal of plastic, identify the regions most affected by plastic waste, develop a business plan for a circular business focused on transforming plastic waste into bricks and understand the risks of plastic production and waste as well as the risks of a business working with plastic waste. In this process, students gain an awareness of the societal context of plastic waste and the varying risks that different demographic categories are exposed to, as well as the role of engineers in contributing to the development of technologies for circular businesses. Students also get to apply their disciplinary knowledge to propose technical solutions to the problem of plastic waste. 

The case is presented in parts. Part one addresses the broader context of plastic waste and could be used in isolation, but parts two and three further develop and add complexity to the engineering-specific elements of the topic.  


Learners have the opportunity to:  

Teachers have the opportunity to include teaching content purporting to: 


Recommended pre-reading: 

Part one:

Part two:


Part one: 

Plastic pollution is a major challenge. It is predicted that if current trends continue, by 2050 there will be 26 billion metric tons of plastic waste, and almost half of this is expected to be dumped in landfills and the environment (Guglielmi, 2017). As plastic waste grows at an increased speed, it kills millions of animals each year, contaminates fresh water sources and affects human health. Across the world, geographical regions are affected differently by plastic waste. In fact, developing countries are more affected by plastic waste than developed nations. Existing reports trace a link between poverty and plastic waste, making it a development problem. Africa, Asia and South America see immense quantities of plastic generated elsewhere being dumped on their territory.  At the moment, there are several policies in place targeting the production and disposal of plastic. Several of the policies active in developed regions such as the EU do not allow the disposal of plastic waste inside their own territorial boundaries, but allow it on outside territories.  


Optional STOP for activities and discussion 


Part two: 

Impressed by the magnitude of the problem of plastic waste faced today, together with a group of friends you met while studying engineering at the Technological University of the Future, you want to set up a green circular business. Circular business models aim to use and reuse materials for as long as possible, all while minimising waste. Your concern is to develop a sustainable technological solution to the problem of plastic waste. The vision for a circular economy for plastic rests on six key points (Ellen McArthur Foundation, n.d.): 

  1. Elimination of problematic or unnecessary plastic packaging through redesign, innovation, and new delivery models is a priority 
  2. Reuse models are applied where relevant, reducing the need for single-use packaging 
  3. All plastic packaging is 100% reusable, recyclable, or compostable 
  4. All plastic packaging is reused, recycled, or composted in practice 
  5. The use of plastic is fully decoupled from the consumption of finite resources 
  6. All plastic packaging is free of hazardous chemicals, and the health, safety, and rights of all people involved are respected 


Optional STOP for group activities and discussion 


Part three: 

The start-up SuperRecycling aims to develop infrastructure solutions by converting plastic waste into bricks. Your team of engineers is tasked to develop a risk assessment for the operations of the factory in which this process will take place. The start-up is set in a developing country of your choice that is greatly affected by plastic waste. 


Optional STOP for group activities and discussion 


Acknowledgement: The authors want to acknowledge the work of Engineers Without Borders Netherlands and its partners to tackle the problem of plastic waste. The case is based on the Challenge Based Learning exploratory course Decision Under Risk and Uncertainty designed by Diana Adela Martin at TU Eindhoven, where students got to work on a real-life project about the conversion of plastic waste into bricks to build a washroom facility in a school in Ghana, based on the activity of Engineers Without Borders Netherlands. The project was spearheaded by Suleman Audu and Jeremy Mantingh. 


This work is licensed under a Creative Commons Attribution-ShareAlike 4.0 International License. 

Any views, thoughts, and opinions expressed herein are solely that of the author(s) and do not necessarily reflect the views, opinions, policies, or position of the Engineering Professors’ Council or the Toolkit sponsors and supporters. 

To view a plain text version of this resource, click here to download the PDF.

Author: Professor Manuela Rosa (Algarve University, Institute of Engineering). 

Topic: Engineering for ecological sustainability. 

Tool type: Knowledge. 

Relevant disciplines: Any. 

Keywords: Curriculum; Engineering professionals; Ecology; Ecosystem services; Natural resources; Interdisciplinary; Biodiversity; Water and sanitation; Climate change; AHEP; Sustainability; Higher education; Pedagogy. 
Sustainability competency: Systems thinking; Collaboration; Integrated problem-solving; Self-awareness; Normative.

AHEP mapping: This resource addresses two of the themes from the UK’s Accreditation of Higher Education Programmes fourth edition (AHEP4): The Engineer and Society (acknowledging that engineering activity can have a significant societal impact) and Engineering Practice (the practical application of engineering concepts, tools and professional skills). To map this resource to AHEP outcomes specific to a programme under these themes, access AHEP 4 here and navigate to pages 30-31 and 35-37. 

Related SDGs: SDG 4 (Quality education); SDG 6 (Clean water and sanitation); SDG 7 (Affordable and clean energy); SDG 12 (Responsible consumption and production); SDG 14 (Life below water). 
Reimagined Degree Map Intervention: Cross-disciplinarity; Active pedagogies and mindset development.

Who is this article for? This article should be read by educators at all levels in higher education who wish to embed environmental and ecological sustainability into the engineering curriculum or design modules. Engaging with this topic will also help to prepare students with the soft skill sets that employers are looking for. 



Engineering has always responded to the societal challenges of humanity, contributing to its progress and economic development. However, the synergetic effects of fossil-based economic growth together with large-scale engineering projects have also caused great pressures on natural resources and ecosystems leading to over-exploitation and degradation. In consequence, in the last decades, a multidimensional perspective on sustainability perspective has arisen, and has been acknowledged by social movements, governments and institutions.   

Meanwhile, this assumes deep epistemological changes, requiring holistic and transdisciplinary approaches that must be considered by engineering professionals, establishing communication based on new ways of thinking. There is the need to interweave disciplines, to establish complementary relationships, to create associations in order to root new knowledge, enabling communication between the sciences. In doing so, transdisciplinary science has emerged, i.e. the science that can develop from these communications. It corresponds to a higher stage succeeding the stage of interdisciplinary relationships, which would not only cover interactions or reciprocities between specialised research projects, but would place these relationships within a total system without any firm boundaries between disciplines (Piaget, 1972).  

Currently, the complexity associated with climate change and the uncertainty of the link between global loss of biodiversity and current loss of public health, are demanding innovative knowledge, needing those holistic and transdisciplinary approaches.  Engineering professionals must therefore give additional attention to ecological sustainability. 


The challenges of sustainability: 

The term “sustainability” portrays the quality of maintenance of something which can continue for an indefinite time, such as biological species and ecosystems. Sustainability is based on a dynamic balance between natural and human ecosystems, in order to maintain the diversity, complexity and functions of the ecological systems that support life, while contributing to prosperous and harmonious human development (Costanza, 1997). This strong perspective of sustainability needs to have a prominent place in land use management which must consider the carrying capacity of natural ecosystems.  

Ecological sustainability in particular aims to maintain the earth’s natural potential and the biosphere, its stock of natural resources, atmosphere and hydrosphere, ecosystems and species. Ecosystems should be kept healthy by preserving their “ecological integrity”, i.e. the capacity to maintain the structure and function of its natural communities, which includes biogeochemical cycles.  

Engineering professionals must therefore understand the global limits for water, land, and energy use (contributing to less atmospheric carbon emissions), and preserve other natural resources, such as nutrients or biodiversity. In the technical decision-making process, they need to understand the ecological impacts of big scale projects, such as transportation infrastructures, dams, deforestation, and others. Alongside other professionals, they need to contribute to the restoration, conservation and preservation of ecosystem services, e. g. support services, production services, regulating services and cultural services. These services result in benefits that people and organisations receive from ecosystems and constitute determinants of well-being (Millennium Ecosystem Assessment, 2005).  

Until now, technical solutions often focused on highly visible man-made structures, many of which stopped or disrupted natural processes. Presently, the importance of regulating natural ecosystem services such as water purification, water supply, erosion and flood control, carbon storage and climate regulation is beginning to be perceived. These are considered as soft engineering tools and must be highlighted by engineering educators and assumed in the practice. 

This ecological mindset would enable solutions that recognise management and restoration of natural ecosystems in order to curb climate change, protect biodiversity, sustain livelihoods and manage rainstorms. Nature-based solutions are a natural climate solution in cities, contributing to the mitigation and adaptation of climate change through green roofs, rain gardens, constructed wetlands that can minimise damaging runoff by absorbing stormwater, reducing flood risks and safeguarding freshwater ecosystems. They are essential in climate refuges for city residents during heatwaves and other extreme climate events. These solutions need specific and new knowledge made by ecologists working with engineers and others, which demands action beyond disciplinary silo, i.e., a transdisciplinary approach.  

Within this context, engineering professionals must consider specific operating principles of sustainability: 

These principles must be considered in engineering education, and require deep changes in teaching, because there is a great difficulty in studying and managing the socio-ecological system according to the Cartesian paradigm which breaks up and separates the parts of a whole. New ecological thinking emphasises holistic approaches, non-linearity, and values focused on preservation, conservation and collaboration (Capra, 1996). The transdisciplinary approach needs dialogic and recursive thinking, which articulates from the whole to the parts and from the parts to the whole, and can only be unchained with the connection of the different fields of knowledge, including knowledge from local communities in specific territories.   

In higher education, engineering students should establish face-to-face contacts with ecology students in order to better understand ecological sustainability and generate empathy on the subject. Engineering students must develop skills of collaboration and inter-cultural communication tools (Caeiro-Rodríguez et al., 2021) that will facilitate face to face workshops with other professionals and enrich learning experiences.  

In the 21st century, beyond the use of technical knowledge to solve problems, engineering professionals need communicational abilities to consider ecological sustainability, requiring networking, cooperating in teams, and working with local communities. Engineering educators must include trans-sectoral and transdisciplinary research and holistic approaches which make clear progress in tackling ecological sustainability. 



The interconnected socio-ecological system must be managed for sustainability by multiple stakeholders.  Engineering professionals need to develop a set of skills and competencies related with the ability to work with other ones (e.g. from the natural sciences) and citizens. Currently, beyond the use of technical knowledge to solve problems, engineers need to consider the sustainable development goals, requiring networking, cooperating in teams, and working with communities through transdisciplinary approaches.  

Education for Sustainable Development is required to empower engineering professionals to adopt strong sustainable actions that simultaneously ensure ecological integrity, economic viability and a just society for the current and future generations. Education is a fundamental tool for achieving the Sustainable Development Goals, as recognised in the 2030 Education Agenda, coordinated by UNESCO (2020).  




This work is licensed under a Creative Commons Attribution-ShareAlike 4.0 International License. 

Any views, thoughts, and opinions expressed herein are solely that of the author(s) and do not necessarily reflect the views, opinions, policies, or position of the Engineering Professors’ Council or the Toolkit sponsors and supporters. 


To view a plain text version of this resource, click here to download the PDF.

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