The concept of a ‘Circular Economy’ (CE) has been gaining traction in business, policy, and academia. It envisions an economy powered by renewable energy in which the value of products and materials are preserved for as long as possible. ‘Design for Circular Economy’ is emerging as a research field as well as a branch of sustainable design practice. Design strategies for the CE include energy and material efficiency, increased utilization, maintenance, repair, reuse, remanufacturing, and recycling.

As more and more products are equipped with digital functionalities and connected to the ‘Internet of Things’ (IoT), new opportunities arise for circular and sustainable design. However, research at the intersection between IoT and CE is still in an early phase and companies are only starting to explorewhat is possible. There is still a lack of research-based design guidance for companies aiming to use IoT to support ‘circular strategies’. In particular, little is known about the actual environmental impact of IoTenabled circular strategies.

This thesis sets out to study how companies can use IoT to support circular strategies. By doing so, the aim is to provide guidance to companies who want to design and implement circular products and services. Focus is placed on understanding the opportunities for companies, as well as the implementation challenges and environmental impact of IoT-enabled circular strategies.

This graduation project explores how the concept of problem sustaining interaction (PSI) patterns in mental development in adolescence can be used for design. In contrast to the currently used Diagnostic and Statistical Manual of Mental Disorders (DSM), which describes psychiatric disorders from only a psychological perspective, the concept of PSI-patterns describes mental health problems as interaction problems. This new holistic approach incorporates interactions within the individual, but also those between people and their environment. To concretise the concept of PSI-patterns, I used the knowledge of system theory. From the research is concluded that factors on multiple levels influence each other; from biological to cultural. The factors in a system form loops that together reach an equilibrium. PSI-patterns consist of smaller, reinforcing feedback loops of which multiple together cause a system to move towards a problematic state. Changing a system requires effort and outside support. By making the patterns insightful, it becomes clear what strategies can be used to create positive change. The physical, social and psychological changes during adolescence make them particularly vulnerable to develop mental problems. There is a taboo around talking about mental health and society turns a blind eye. This causes adolescents when they struggle mentally to feel abnormal and alone, to lack knowledge and understanding to talk about their struggles and to feel not taken seriously when told that troubles are ‘just part of life’. To support adolescents in their mental development I introduce the design concept “The Bumpy Road”. The Bumpy Road supports adolescents to learn to understand their feelings by recognizing them in others. It is a platform with a variety of podcasts in which adolescents share personal and authentic stories about times in adolescence where they struggled. The problematic patterns of the storyteller are unravelled and explained to listeners in conversation with a pattern expert. The patterns that are discussed in the podcast are linked to other stories on the platform that include their version of the pattern. By making patterns insightful, listeners understand why problems keep occurring and get direction on how to navigate towards a more sustainable situation. The Bumpy Road teaches listeners the language to talk about struggles, normalizes them and provides advice on how to help themselves or support others. This project brings PSI-patterns from a conceptual level towards a concrete and validated design service, and thereby proves that PSI-patterns are a suitable framework for design.

Festivals are a growing trend, and although being a temporary event, most festivals have vast material flows with a large negative impact on the environment. The Dutch festival Lowlands, a three-day event, for example uses 300.000 kwh of electricity generated by diesel-fuelled generators, 10.000 m3 water and 500.000 kg of solid waste (Amsterdam Institute for Advanced Metropolitan Solutions, 2017). As a result, the attention is growing to find ways how to organize more sustainable events. Initiatives like Green Events support this development, by seeing the festivals as an ideal testing ground for new sustainable innovations.
One festival taking the green developments at heart to become a more sustainable event is DGTL revolution.Throughout the year DGTL Revolution is searching for new technologies and innovations, they can introduce at the festival to reduce their waste, lower their emissions but moreover create awareness and stimulate sustainable action amongst their visitors (DGTL Revolution, 2017). A project Revolution has focused on this year, is their plastic material stream.
Despite of the hard cup and deposit system which is in place at the festival, the festival still has a large amount of single use plastic water bottles. The need for a change in our current wasteful plastic economy has been a subject which is being discussed more and more. The single use plastic bottles form an opportunity for DGTL festival to discover circular ways of processing PET bottles, minimizing their plastic footprint and taking the visitors along in this vision.
This graduation project has started with an extensive research to the current sustainable efforts of festivals, the view of visitors on those efforts and the current challenges in plastic recycling outside the festival context. This is done through desktop research and several interviews with festival visitors and experts. A key finding of the research were the several barriers visitors experience, stopping them from behaving pro-environmental, like collecting and separating plastic at a festival or in their home environment. DGTL should facilitate a deposit system which overcomes those barriers of individuality, responsibility and practicality.
The following design brief was formulated from all the insights of the research; ‘How can DGTL positively change visitors attitude towards plastic recycling, using the deposit system at DGTL as a vehicle, illustrating its aim and result increasing people’s feel of responsibility.’
During the exploration phase new innovations in plastic recycling have been approached to collaborate with DGTL festival, aiming to process the plastic bottles into valuable resources again. Next to those innovations, the focus was on getting the visitors more involved in the goal of the deposit system. Overcoming the barriers by increasing the practicality of the system and showing them the aim and result of the system. This could have an effect on their perspective towards plastic recycling, and stimulate them to copy this behavior outside of the festival context.
The final concept which was implemented at the festival consisted of several elements. The central point was called the resource street. Here all the materials of the festival came together at the recycle hub were they were checked and separated (Figure 2). Furthermore the visitors were able to see the chemical recycling innovation pyrolysis, turning bottle caps into oil, a plastic container where all the plastic bottles were collected, showing it massive amount to the visitor as well as explaining how the bottles will be recycled into high quality rPET.
This concept is further supported by several decentralised designs namely transparent collection behind the bars, signing with information about the system and last mobile collection vehicles. All those elements have been implemented at the festival and evaluated, through interviews, a questionnaire and some data analysis about the collection.
This master thesis describes the first steps a festival can take, to move towards a more transparent resource handling, through which valuable resources can be regained from plastic bottles. At the same time, the visitor is involved in this system, leading to a larger effect by improving their perspective and behavior towards plastic recycling.

In the process of urbanization, cities are becoming ever larger and denser, a process accompanied by a dramatic decrease in water permeable surface area. In addition to this, due to climate change, several areas are experiencing extended periods of heavy rainfall and serious droughts, resulting in an increasing water problem in many cities.
A major challenge is to find a good balance between measures preventing an overload of rainwater leading to urban flooding and providing a solution for times when there is a scarcity of water, which currently result in unwanted effects like restrictions for water use.

The Dakdokters is a company that works on a solution for these problems using an underused place, rooftops. Their core business is designing and installing green roofs in order to increase the benefits of greenery in cities. In 2013 they realized that their green roofs could maybe be combined with an open water storage system that could serve as a water buffer. This was the start of a project called “Polder Roof” (polderdak).
The Polder Roof makes use of a WRB (Water Retention Box) layer underneath a green roof. Large amounts of rainwater which would normally be discharged in the sewage system, are temporarily stored in these boxes on the roof. This not only reduces the pressure on the sewage system during periods of heavy rainfall, but the stored water can subsequently be used for e.g. irrigation of the green roof, or for applications like toilet flushing, leading to a decrease in the use of high quality tap water. Technically it is necessary to be able to precisely control the amounts of water stored. This is achieved by a semi-automatic system, called the Smart Flow Control (SFC), which uses various sensors and electric actuation for control. In addition, it can be controlled over the internet by external operators.

Assignment
Currently several prototypes of SFC controlled Polder roofs are installed on 7 different rooftops in Amsterdam. These prototypes function as a proof of concept. However, for the final market implementation some parts of the concept need improvement:
First of all there is the costs aspect. In order to be competitive with other water retention solutions, the Polder Roof should become less expensive per m3 of water storage. A decrease in investment costs as well as in the yearly costs of maintenance and data subscriptions are needed.
Secondly, the current products fail too often, leading to high maintenance costs.
Thirdly, although not important when it comes to functionality, the design of the system must be aesthetically pleasing, especially in cases where the green roof is going to be combined rooftop park-like settings on the rooftop, visited by e.g. personnel of companies.

The assignment of the Dakdokters for the project described here, focused foremost on the design of the regulatory valve and its housing. In the course of the project the rest of the system was also analysed to identify any other optimizations needed.

The outcome of the project can be divided in the following analyses and results:

Step 1: Exploring the context
The input of different stakeholders was obtained in interviews, especially with a view to critically assess the wanted functionalities of the Polder Roof, since a reduction in these could possibly result in a less complex product, reduced parts costs and increased reliability due to less parts that could fail. Not just the market context, but also the technological implications of the roof context was analysed.

Step 2: Analysis of the current product
All current parts were critically analysed with respect to their functionality, costs and reliability. The reliability analysis not only comprised to regular wear through usage, but also to sensitivity to external factors, such as water pollution. These analyses corroborated the idea that the biggest improvements could be made by redesigning the valve and housing of the SFC, concomitantly also improving the installation procedure. The latter is important since in many cases multiple SFC’s need to be placed , due to the fact that roofs are never totally flat but have a slight slope, requiring multiple basins , each with their own SFC for the optimal water storage. Therefore I first concentrated on redesigning the valve and its housing.

Step 3: Analysis of the current product
These analyses led to a personal design vision of the full system. Together with a function map that was checked by the company and its most important partner, Optigroen, this resulted in a complete overview of all desired functionalities of the new Polder Roof and a program of requirements.

Step 4: Product development of the valve and the housing.
Multiple brainstorm sessions resulted in several new ideas, which were evaluated in expert meetings, using prototypes and (CAD)-sketches. I designed a new way of operating the valve, using a rotational actuator. The expensive, non-functional and not very aesthetically pleasing windmill shape of the current housing was simplified into a droplet shape, making it cheaper to produce while still being iconic. This housing was optimized for easy manufacturing and installation and improved safety of the system. These concepts were bundled into a final new concept.

Step 5: Embodying the concept
In the final design phase the concept was further embodied. Several optimizations using tests with a full scale prototype and meetings with experts led to final concept of the SFC which is focused on an easy and cost-effective production and installation process. A concept for the parts needed for the connectivity of all SFC’s on the roof, using a new micro-controller, reducing the investment and yearly costs and a new scenario for the software using rain radar data was designed.

Step 6: Evaluation of the new product.
In the final phase an evaluation was done on the functionality, the reliability, the costs and the aesthetics of the new design. These evaluation proved that a the new design is less expensive, easier to install on different types of roofs, easy to maintain and more reliable. In addition, it proved aesthetically pleasing to the stakeholders.
Apart from these conclusions the results of these evaluations led to recommendations for further development of the SFC, of which the most important is the following: In order to accurately test the new design it is necessary to built a full size test set up with which roof conditions can be simulated. This set-up should including multiple variations in roof lay-out and amount of water storage. It can similarly act as a demonstration model

During my master thesis, I developed a method for designers to establish self-sustaining product systems in third world countries. This journey started off with the quest to fight plastic waste pollution of the rural areas in Kenya. After thorough field- and technological research, I developed a toolset that allows locals to transform plastic waste into products that allow for clean rainwater collection. From this experience, I drew insights, which can be applied for product design for development aid in general. These insights are formalized in a framework for designers.

I came to understand that the easiest way to give locals an incentive to clean up their environment is to show the value that the plastic waste has as a resource. These resources could be used as building materials to produce products that are highly needed in the everyday lives of Kenyans, like rooftops, gutters and water pipes. The advantage of looking at local resources from waste in this way is that users have access to all resources, needs and production methods and can thus be self-sufficient.

As I argue in this thesis, this approach is opposed to the way many other Western aid initiatives are tackling problems for African locals at the moment. Through introducing a seemingly meaningful product, a social problem might be successfully solved. However, after this product’s breakdown, only Western knowledge and resources can be employed to repair it. Hereby, an ongoing dependency between Western aid initiatives and African users is created.

In the first chapter, I write about aid initiative in Africa and argue about their fallacies as local problems are not looked at from a local perspective. Product-based aid projects will be discussed in detail to understand what impact product design has and how it can be improved.

In the second chapter, I will look at the problem from another perspective. I show how plastic waste is harming the ecological system in Kenya and how this waste can be taken as resources to solve local problems.
As a solution to the social needs and the ecological challenges, I propose a model of Self Sustaining Product Systems (SSPS) in chapter three. In these systems, local Africans are the both the actors and beneficiaries. The SSPS model allows for solving local problems with local resources. In order to design and implement SSPS, I introduce a framework for designers called Ripple (Resource Innovation for Products that Promote Local Empowerment) in chapter four. In the Ripple framework, I explain how to analyse, ideate, conceptualize, prototype, test and disseminate self-sustaining product systems. Each step is accompanied by depictions of the rainwater collection project in Kenya for clarification.