Circular Economy, Sustainability and Business Opportunities

people management strategies

By Rashmi Anoop Patil, Sudiptal Seal, and Seeram Ramakrishna



Humans exist only on this planet earth and heavily dependent on the natural resources and ecosystems. According to some scientific estimates, humans inhabited the earth for about 300,000 years, and the human civilizations dated back to 4,000 BC (Victor, 2018). For most of human history, they have lived sustainably and pretty much in harmony with the nature. However, industrialization accelerated the pace of humans controlling nature for their lifestyle. Industrialization also catalyzed the linear economy in which take-make-use-dispose culture is accentuated. In the last hundred years, the rapidly growing as well as urbanizing human population is excessively consuming the planet’s limited resources and polluting the ecosystems. This is also contributing to the extreme weather conditions and rise in sea levels.

This calls for a transition from our current unsustainable linear economy to a more sustainable circular economy. This change is appreciated only when it comes with a promise of positive outcomes for all stakeholders. In this article, we have explained how a circular economy is beneficial to humankind for a sustainable future in the long run. The transition also requires investments in infrastructure facilitating circularity of materials, production of clean energy, and innovations to redesign the processes and services.

Circular economy and sustainability have become a burgeoning consciousness in the recent years. To standardize the concepts, the International Standards Organization (ISO) formed a new circular economy technical committee. According to the ISO, a circular economy is one where it is restorative or regenerative. Also reuse/reutilization should lead to reducing waste by careful evaluation of resources.

The ISO also defines sustainability as a state of the global system, which includes environmental, social and economic subsystems, in which the needs of the present are met without compromising the ability of future generations to meet their own needs. It’s evident from ISO’s vision that circular economy and sustainability are intricately connected and will feed on each other.

The authors defines that circular economy is a way of living in harmony with our ecological systems and restoring them. To do so, we advocate the use of Life-cycle Analysis tool, nano and digital technologies empowering Industry 4.0 with the 3Rs – Reduce, Reuse, Recycle. The authors also suggest that the change to circularity and sustainability will be better appreciated and embraced by every individual when it becomes a part of our education curriculum across the globe. This should drive inter-disciplinary innovations to foster sustainability (Murray et al., 2017).

Fig. 1. Infographic summarizing the key discussion points of this article emphasizing the subtle relationships among circular economy (CE) and sustainability concepts, influence of digital technologies via Industry 4.0, nanotechnology, life cycle assessment, bottom-up & top-down approaches, indispensable role of circular economy education, and new business opportunities.


Cities and Linear Economy

Rapid industrialization in the 20th century provided a major impetus for global urbanization. This led to the development of cities around industrial areas contributing largely to the socio-economic progress around the world (Gollin et al.,2016). Cities turned into centers of education and employment for a significant portion of the growing population. To date, people are continuously migrating from rural to urban areas in pursuit of opportunities and a better lifestyle. However, this economic growth came at a huge cost of undesirable effects on the environment as well as human health. Urban areas being densely populated and packed with industries consume more than two-thirds of the total energy consumed (mostly derived from fossil fuels) and accounts for over 75 – 80 % of global greenhouse gas emissions (Satterthwaite, 2008). The industrialization has also resulted in the exploitation of natural resources for manufacturing on a large scale to feed the ever-increasing consumer appetite. In the past 40 years, the global use of material resources has almost tripled, from 26.7 billion tonnes in 1970 to 84.4 billion tonnes in 2015, and is expected to double again to between 170 and 184 billion tonnes by 2050 (PACE, 2019). This practice of over-consuming limited natural resources without replenishing them leads to unsustainable growth. In addition to this, the current linear economy model where we procure resources from nature for manufacturing desired products and dispose of them into the environment at their end-of-life is polluting our ecosystems and affecting human health. Growing research evidence points out that man-made chemicals are causing major threat to the sustainability of human life. The low dose adverse effects include disruption of the endocrine system which in turn contributes to the sterility in humans (Balabanic et al., 2011; Poongothai et al., 2009; Tsutsumi, 2005; Massaad et al., 2002). The only way to adequately protect the human population from these effects is to move from the current materials systems and linear economy to non-toxic materials and circular economy (Murray et al., 2017).

In the past 40 years, the global use of material resources has almost tripled, from 26.7 billion tonnes in 1970 to 84.4 billion tonnes in 2015, and is expected to double again to between 170 and 184 billion tonnes by 2050

Cities occupy just 3% of the Earth’s total land area yet, they are housing more than half of the total world’s population (UNDP, 2015a). In 2018, the urbanized population was 4.2 billion people (55% of the world’s population) and by 2050, it is expected to rise to 6.5 billion people (66% of the world’s population) (UNDP, 2015a). Cities are also the centers of economic development and generate about 80% of the global Gross Domestic Product (GDP) (UNDP, 2015a). This comes with the enormous usage of material and energy resources which has put tremendous pressure on the resources’ supply chain. The current linear economy model has also led to the generation of an unmanageable amount of waste with adverse implications on the environment. According to the World Bank estimates, the total solid waste generated in the world’s cities will increase from 2.01 billion tonnes in 2016 to 3.40 billion tonnes in 2050 (Kaza et al., 2018). A major portion of the solid waste generated is either landfilled or incinerated polluting the ecosystems and adding to the carbon footprint of the cities (Chandrappa and Das, 2012). Let us consider a few examples to understand how cities are managing the resources available.

Singapore, a resource-scarce city-state depends on other countries for resources such as natural gas, food, water, and other consumer products. The city with a population of around 5.8 million, generates over 7 million tonnes of waste per year and nearly 40% of it is incinerated and disposed of (NEA-Singapore, 2019). At this rate, Singapore’s only landfill will run out of space by 2035 (MEWR-Singapore, 2019). In addition to this crisis, 95% of the total energy consumed by Singapore is currently from imported natural gas (EMA-Singapore, 2016). The city contributes around 0.11% of global carbon emissions (NCCS-Singapore, 2012).

New York City (NYC) which is almost of the same size as Singapore, is the most densely populated metropolitan in the United States with over a population of 8 million as of 2018. According to the NYC Dept. of Sanitation (NYC Mayor’s Office), NYC generates over 14 million tonnes of solid waste per year which accounts for 1.66 million metric tonnes of Greenhouse Gas (GHG) emissions with nearly 20% waste recycling rate (ICLEI-USA, 2011). The total GHG emissions of NYC is nearly 55 million metric tonnes. (MacWhinney and Klagsbald, 2017)

India is one of the fastest developing economies in the world. However, its metropolitan cities such as Delhi, Mumbai, Kolkata, Bangalore, and Chennai are becoming less sustainable by the year. Mumbai with a population of around 25 million, is generating over 2.75 million metric tonnes of solid waste per year (collated by the Central Pollution Control Board, India). Except for a small portion of biodegradable waste being composted or used as feed for biogas plants, the majority of the waste is being dumped in the landfills (Sharholy et al., 2008; Narayana, 2009). According to a study in 2014 on carbon emissions of major Indian cities, Delhi tops the list with 38.6 million metric tonnes emissions followed by Mumbai, Kolkata, Chennai, Bangalore (Ramachandra et al., 2014). Cities such as Bangalore, Chennai, Delhi, Mumbai, and Kolkata are facing scarcity of drinking water every year due to the overuse and misuse of groundwater, expansion of cities by using land where there were natural lakes, and contamination of freshwater resources (Jain, 2011).

Chinese cities such as Beijing and Shanghai are overpopulated with 21.54 million and 24.24 million as of 2018. Beijing generated over 9 million tonnes of domestic municipal solid waste in 2018 and nearly 40% of it is landfilled and the rest is either burned or biochemically treated. The situation is similar in Shanghai and other major industrial cities in China (Zhang et al., 2010; Chen et al., 2010). To add to this environmental problem, China, well known for its industrial growth and production, is the highest contributor to global carbon emissions. (Zhang and Cheng, 2009; Dhakal, 2009; Cao et al., 2006).

From the above examples, we can ascertain that the developed economies produce more waste and have a higher carbon footprint than the developing economies. This unsustainable consumption and disposal of resources needs to be replaced by a sustainable economic model starting from our cities. This will reduce the burden on the resource supply chain and consequently, save the environment.


Circular Economy Emulates Nature.

Waste does not exist in nature, because each organism contributes to the health of the whole. One organisms waste becomes food for another. Nutrients flow perpetually in a regenerative, cradle to cradle cycles of birth, decay, and rebirth. Waste equals food.

William McDonough, Architect, Co-Author of Cradle to Cradle: Remaking the Way We Make Things (2002) and Author of Something Lived, Something Dreamed (2003) and Positive Cities (Scientific American, July 2017).

A circular economy is a restorative and regenerative system of closed loops in which raw materials and products circulate eternally eliminating wastage as if mimicking the circularity of elements in a natural ecosystem such as forest as illustrated in Figure 2. It also depends on renewable energy sources such as sunlight and wind instead of fossil fuels. Such a system is the key to achieve sustainability.

Nature inspires the concept of circular economy where resources are valued the most (Korhonen et al., 2018). Every element of nature is continuously in use by turning waste into resources repeatedly, using principles such as reduction, reuse and recycle (3Rs) (Figure 2). Products and services are also evaluated for their environmental impact at all stages of life-cycle. Such an assessment is important to reduce their harmful effects on nature. This calls for innovation of new composite materials that are biodegradable and can be recycled with little or no impact on the environment. Circular economy and sustainability should inspire innovations which are necessary solutions to improve the current waste recycling rates, mine resources from the waste consuming fewer resources in the process, which consequently minimizes the damage to the environment and human health.

Fig. 2. A schematic on Circular Economy emulating nature. In the natural ecosystems, using the biological nutrients, the plants produce food which is consumed by animals for survival. The biological waste generated is decomposed into nutrients, and other resources in nature such as water are restored into the system through natural cycles. To mimic nature through the circular economy approach, products and services are designed & produced with minimum resources for judicious consumption and completely recycled for maintaining the circularity of materials thereby eliminating their adverse effects on nature.


The circular economy is not just limited to the reuse and recycling of material resources. It also emphasizes the use of renewable energy resources such as biogas, wind and solar energy. This again is inspired by nature where plants use the nutrients in the decomposing biomass, water and the sun’s energy to produce food. To emulate the natural producers, circular economy promotes production and consumption of sustainable and greener energy instead of burning non-renewable fossil fuels.


The circular economy is not just limited to the reuse and recycling of material resources. It also emphasizes the use of renewable energy resources such as biogas, wind and solar energy.

Circular Economy Facilitates UN Sustainable Development Goals.

The circular economy can be leveraged to achieve multiple Sustainable Development Goals (SDGs). It holds particular promise for achieving SDGs, including goals 6 on clean water, 7 on clean energy, 8 on economic growth, 11 on sustainable cities, 12 on sustainable consumption and production, 13 on climate change, 14 on oceans, and 15 on life on land, as shown in Figure 3.

Fig. 3. Schematic illustration of the United Nations Sustainable Development Goals (UN SDGs) that can be achieved by adopting Circular Economy principles. The circular economy vision has influenced multiple UN SDGs, particularly goals 6 on clean water, 7 on clean energy, 8 on economic growth, 11 on sustainable cities, 12 on sustainable consumption and production, 13 on climate change, 14 on oceans, and 15 on life on land.


The exploitation of freshwater resources and mismanagement of wastewater has resulted in the scarcity of drinking water on a global scale. If this trend continues, it is projected that by 2050, a quarter of the world’s population will suffer severe water shortages (UNDP, 2015e). Applying the principles of the circular economy such as reducing the usage of water and recycling the wastewater instead of allowing it to pollute our waterways will help us achieve the SDG 6.

As discussed in the previous section, using clean energy is a core idea of a circular economy. Decoupling energy derived from fossil fuels reduces carbon emissions by 60% which is the main contributor to climate change (UNDP, 2015f). Also, renewable energy sources are sustainable in the long run to cater to the needs of the growing population. A complete transition to cleaner energy sources such as solar, wind and thermal power is vital to achieve SDG 7 by 2030.

In the current economic system, economic growth has gradually slowed down in the past few decades leading to widening inequalities in wealth and unsustainable production (UNDP, 2015g). The transition to an alternative sustainable circular economic system is difficult initially but will stabilize the economic growth for generations to come. It will also provide new business and job opportunities that can lead to enhanced productivity. Hence, adopting a circular economy will contribute to fulfilling SDG 8.

In the earlier discussion on cities and linear economy, it was very clear that our cities have become unsustainable as a repercussion of the linear economic system and improper urban planning and management. Adopting a circular economy, re-designing the cities to promote circularity and changing the way we live to imitate natural ecosystems is the key to SDG 11.

Sustainable production and consumption is the core idea behind the circular economy. Creating circular material flows, minimizing the usage of natural resources and the elimination of toxic chemicals to reduce our ecological footprint which forms the basis of a circular economy will lead to the SDG 12‭.‬

Climate change is an aftereffect of human impact on the ecological systems. The exploitation of natural resources at a rate that nature cannot replenish it fast enough and emission of greenhouse gases creating an imbalance in the natural systems are causing long-lasting irreversible changes to the climate. This has resulted in geophysical disasters and economic losses (UNDP, 2015b). Reducing the human impact on the ecological systems through a circular economy will contribute to the climate action goal (SDG 13).

Oceans play a vital role in maintaining the health of our planet. Oceans act as a buffer to the impacts of global warming as they absorb ~30% of carbon dioxide produced by humans’ activities and produce ~70% of the total atmospheric oxygen. It is a major source of protein for humans and 3 billion people around the world depend on marine and coastal biodiversity for their livelihood (UNDP, 2015c). Anthropogenic debris majorly constituting plastics and industrial wastes have polluted the oceans to alarming levels, converting them into a toxic soup endangering hundreds of species of marine biota. A circular economy stemming from the zero-waste scenario can save the oceans and the dependent biodiversity (including the humans). Also, human marine activities such as fishing, aquaculture have to become more sustainable by limiting the consumption of ocean-based resources. These can contribute to fulfilling the SDG 14.

Unsustainable agricultural and industrial activities, deforestation, degradation of drylands and freshwater resources, illegal trades of animals and plant products have created an imbalance in our ecological systems. A multitude of consequences of this imbalance such as loss of natural habitats and biodiversity, climate change, global food and water security, and conflicts, need immediate action (UNDP, 2015d). Implementing circularity of materials and sustainable consumption can reduce the stress on natural resources which in turn allows natural systems to replenish the resources. Reducing carbon emissions by using cleaner energy can contribute to maintaining the ecological balance. Thus circular economy can complement SDG 15.


Circular Economy Metrics for Sustainable Cities

The circular economy metrics for cities encompass both, metrics for environmental impacts and economic growth/stability which contribute towards sustainability. However, there is no established set of CE indicators for measuring the sustainability of cities and in many cases data to analyze the indicators is not available. In a way, the rate of successful achievement of SDGs mentioned in the previous section can be considered as circularity metrics. However, there is a need for a set of measurable and comparable indicators of circularity. This set should include the measurement of material flows from input to output with wastage in different economic sectors, sources of energy and consumption statistics, domestic waste generated and recycling rates, total greenhouse gas emissions of the city, the environmental pollution estimates and also the GDP with economic stability parameters.

The Economist Intelligence Unit (EIU) in cooperation with Siemens has developed the Green City Index for comprehensively evaluating the major areas of urban environmental sustainability of cities across the world (EIU, 2012). This index measures cities with a set of 30 indicators across eight categories as shown in Figure 4. These categories include CO2 emissions, energy, buildings, land use, transport, water and sanitation, waste management, air quality, and environmental governance. The 16 quantitative indicators that use data from official public sources, and other 14 are qualitative assessments such as the city’s environmental policies. Although the Green City Index provides standard metrics to compare the environmental sustainability of different cities, their dependency on publicly available data may have compromised the accuracy of such comparisons.


Fig. 4. Schematic illustration of the Green City Index and the Global Cities index and Outlook as outlined by A.T. Kearney. The Green City Index provides a comprehensive set of factors for evaluating the urban environmental sustainability of cities across the world. Reproduced from the Green City Index report (EIU, 2009)(c 2012 by Siemens AG.). The Global Cities Index and Outlook provides guidelines for measuring the economic progress of cities. The Green City Index and the Global Cities Index and Outlook together can serve as circular economy metrics for the design and development of sustainable cities.


The A.T. Kearney Global Cities Index and Outlook provides a set of indicators to measure the economic progress of cities which takes into consideration the current conditions and factors contributing to future economic progress (Hales et al., 2019). The indicators measuring economic progress include business activities, human capital, information exchange, capital investments and GDP, innovations and patents, economic policies and governance as shown in Figure 4. These indicators encompass both static and dynamic dimensions of urban economic development. The information used to calculate these indices is obtained from publicly available sources.

The environmental indicators of the Green City Index together with the economic indicators of the A.T. Kearney Global Cities Index and Outlook put together can be a comprehensive set of circular economy metrics for sustainable cities. These indices have been used to define and indicate the performance of ‘smart cities’ as well.


Life Cycle Assessment (LCA) of Products and Services

Life cycle assessment is an analysis technique to assess environmental impacts associated with all the stages of a product’s (or service’s) life, from raw material extraction through materials processing, manufacturing, distribution, use to disposal or recycling (Guinee, 2002; Finnveden et al., 2009). LCA is a useful tool to evaluate true sustainability or the circularity of products. Otherwise, what may seem like a better replacement for the existing product/service is shifting or creating a new unintended problem to the ecosystem. The intention behind the LCA is to determine the full range of environmental effects assignable to products (Kloeper, 2008) and services by quantifying all inputs and outputs of material flows and assessing how these materials flow affect the environment.

Let us consider a couple of examples to understand how LCA can help us identify the products/services that have minimal impact on the environment. LCA study by the Danish Environmental Protection Agency for breaking even environmentally w.r.t. a fossil fuel-based single-use plastic bag suggests that a polypropylene bag should be used for 37 times, a paper bag should be used for 43 times and a cotton bag should be used for 7,100 times. An innovative alternative to the single-use plastic bags can be nature biomass-sourced biodegradable polymer bags (Bisinella et al., 2018).

Another LCA analysis by Singapore researchers suggests that importing fresh pork to Singapore from Brazil contributes to three times higher greenhouse gas emissions than importing from Australia. Also, 60% of the energy used in transporting food items to Singapore is used for fresh air-flown meats and fish which accounts for 3.7% of the food consumed. Perhaps importing food from neighboring countries or produced domestically will lower the carbon footprint. It has also been suggested that plant protein-based cultured meat or vegan meat has a lower carbon footprint than the animal-sourced meat.


Industry 4.0 enabling Circular Economy

The world today is witnessing the beginning of the fourth Industrial Revolution or Industry 4.0. This revolution, unlike the past three revolutions, is driven by two primary factors – automation and data. The unique but often overlooked fact is that unlike the previous industrial revolutions which generated waste, the present industrial revolution seeks to minimize or eliminate waste and greenhouse gas emissions through redesigning the production processes and enabling industrial symbiosis (waste from one industry can serve as a raw material for another). This fact links this objective of Industry 4.0 with the principles of a circular economy.

The rise of a new digital industrial technology, known as Industry 4.0, is a transformation that makes it possible to gather and analyze large amounts of data across machines, enabling faster, more flexible, and more efficient processes to produce higher-quality goods at reduced costs. This manufacturing revolution will increase productivity, shift economics, and foster industrial growth. Advanced digital technologies empowering Industry 4.0 such as advanced robotics, machine learning, internet of things, cloud services, big data, smart sensing, and smart tagging for manufacturing (Figure 5a), will transform production (PACE et al., 2019; Nascimento et al., 2019). It will lead to greater efficiencies and change traditional production relationships among suppliers, producers, and consumers as well as between humans and machines.

With the emergence of industrial internet-of-things and articial intelligence, industries are getting remodeled with cyber-physical systems for manufacturing and supply chains. These systems are smart, communicate within the local network and across networks, self-diagnose problems, procure resources at the appropriate time and can interface with humans to optimize the processes. This results in utilization of less raw materials, energy and consequently reduction in waste. Thus, Industry 4.0 facilitates circular economy principles, as illustrated in Figure 5b.

Fig. 5. Industry 4.0 for Circular Economy. a, Schematic illustration of digital technologies enabling Industry 4.0. b, Schematic illustration of Industry 4.0 enabling Circular Economy. Smart manufacturing, smart supply chain and a smart workforce facilitate the reduction in resource & energy consumption, and waste generation by optimizing the industrial processes.


For instance, Intel, a leader in microelectronics manufacturing, has implemented sustainability innovations across its expansive ecosystem of manufacturing, technology development, and global supply chain. They have improved the wet process packaging industry in SE Asia by reducing the usage of harmful chemical consumables and water with greener alternatives and a dry process respectively. Intel is also providing edge computing and AI technologies to empower leading manufacturers to realize the transformation to Industry 4.0. It is estimated that the annual size of the Digital Universe – the data we create and copy – will reach 180 zettabytes by 2025 as a result of the massive flow of every-day data. This gives rise to the need for energy-efficient computing and memory, with a lower resource footprint. Ground-breaking innovations in this domain are essential for the future of our Digital universe, and Intel is currently leading in this area.


Nanomaterials and Nanotechnology for Circular Economy

In recent years, advanced nanomaterials and nanotechnology have enabled sustainable designs for a circular economy. The continuous pursuit of high-performance materials in terms of weight, strength, flexibility, having special properties such as self-repairability and performing multiple functions to replace the materials in use/for new applications, have changed the landscape of desirable materials. The advancements in material science and technology have offered designers a wide range of greener materials (Varma, 2012; Lee et al., 2010) for a multitude of applications.

The new and green nanomaterials and nanotechnology are being employed in industrial solid waste treatment processes to enhance the materials extraction rate, wastewater treatment, greener building designs, agriculture, clean energy production & storage (Chen et al., 2012), secondary raw material extraction, and other applications to replace conventional materials with a higher ecological footprint, facilitating circular economy (Figure 6).

Fig. 6. Schematic illustration of how nanomaterials and nanotechnology are enabling the circular economy. Nanotechnology applications in environmental sensing and detection of pollution, waste treatment and materials recycling, energy-saving and greener energy production, and new nano-materials with lower ecological footprint than conventional materials play an important role in driving a circular economy.


The applications of nanotechnology in environmental management and resource conservation are more advantageous than the conventional techniques. Nanotechnology is used for monitoring and sensing environmental components such as air & water, remediation and treatment of water contaminated with heavy metals, pesticides, organic compounds (Theron et al., 2008; Qu et al., 2013), air filtration treatment, and soil treatment (Ibrahim et al., 2016). Nanomaterials have extensive applications in energy saving in several respects such as super-insulating materials for temperature control, lighter and stronger materials for automobiles, efficient lighting devices and fuel cells and also have promising potential for renewable energy production (Serrano et al., 2009; Mao and Chen, 2007) with nanostructured materials based photovoltaics (Varghese et al., 2009). Nanotechnology can propel circularity by providing better air and water quality and in maintaining the water resources in a closed loop along with energy conservation and production of renewable energy.


According to Accenture estimates, the transition towards a circular economy represents USD 4.5 trillion global growth opportunity.

Business Opportunities

Every problem/challenge is a business opportunity and entrepreneurship has a vital role in driving economic progress. According to Accenture estimates, the transition towards a circular economy represents USD 4.5 trillion global growth opportunity by 2030. The European circular economy opportunities report projects that adopting circular economy principles could not only benefit Europe environmentally and socially but could also generate a net economic benefit of 1.8 trillion by 2030. This huge leap in global economic growth as a result of adopting a circular economic model is also sustainable in the long run.

As the circular economy is based on eliminating waste and creating value for resources, it opens up new avenues for businesses such as waste recycling and resource recovery, and alternatives for products and services that have a higher ecological footprint (Figure 7). Many companies and startups are realizing the potential of these opportunities and are coming forward with new business models to suit the requirements of the future market trends. For example, MARS, M&S, Pepsi Co, The Coca-Cola Company, Unilever and Werner & Mertz have pledged to use 100% reusable, recyclable or compostable packaging by 2025 in collaboration with the New Plastics Economy Initiative. In the fashion industry, 64 companies became signatories to the 2020 Circular Fashion System Commitment, promising to accelerate the transition to a circular fashion system.

Investments in new infrastructure propelling the circular economy is essential to redesign the industrial processes, supply chain and manage the waste to recover resources (Figure 7). Innovations are necessary in product/process design, materials engineering at the micro- and nanoscale, and computational modeling so that humans learn to design out waste and pollution, maintain the products and materials in use for longer periods, and allow natural systems to regenerate. The United Nations Sustainable Development Goals serve as a guideline for innovators and industries to align their interests to make this planet a better place to live.

Fig. 7. Schematic illustration of the circular economy (CE)-driven business opportunities in various business sectors. These domains such as circular resource and energy supplies, resource recovery from waste, symbiosis between various industrial sectors for raw materials and maximum utilization of resources, offering products as a service, product life extension, and redesign of products with circularity in mind are currently less explored and have the potential to achieve sustainable economic growth.


The social and green entrepreneurs are considered as the drivers accelerating the transition to a circular economy. These new business ideas are oriented toward environmental and social values than being purely commercial. These enterprises offer products and services such as renewable energy, waste management, recycling, green building, organic food or eco-tourism to reduce the environmental impacts of economic activities through innovations and effective & efficient business models.



The authors are thankful to the National Science Foundation (NSF), USA for funding the Nano-Micromaterials for Circular Economy and Sustainability in the East Asia Pacific conference (CBET 1929899), and Dr. N. Savage, Program Director, NSF.

About the Authors

Rashmi Anoop Patil, (Email: [email protected]) is a circular economy enthusiast and an engineer by profession with a Bachelors in Electronic Engineering from Visveswaraiah Technological University, India. As a freelance circular economy advocate, she is currently researching on Circular Economy concepts at the National University of Singapore (NUS). With Prof. Seeram Ramakrishna (Chair, Circular Economy Task Force, NUS), she has developed research reports on Singapore’s pursuit of circular economy, worldwide e-waste management legislations, and the current trends in solutions for the ocean plastic problem. She is passionate about sustainable development and ecofriendly businesses.

Prof. Sudipta Seal, Trustee Chair, Pegasus Professor, University Distinguished Professor, is currently the Chair of Department of Materials Science & Engineering at the University of Central Florida (UCF), USA. He is the director of the UCF’s Nano Technology Center and served as Board of Trustees of American Society of Materials Intl. He is a Fellow of ASM, IoP, AAAS, AIMBE, ECS, AVS, MRS, National Academy of Inventors, and Royal Society of Chemistry. He has been recently inducted to World Academy of Ceramics, and Florida Inventors Hall of fame (71 issued patents). He won the Office of Naval Research Young Investigator award and ASM’s Albert Sauveur Achievement Award in Materials Innovation. His h-index is 89. He is an editorial board member of NATURE Scientific Reports. He is on the editorial board of Materials Circular Economy. He is a co-organizer of NSF, USA sponsored conference on materials and circular economy and sustainability ( He received his B-Tech from IIT-Kharagpur India, MS from University of Sheffield, and PhD from University of Wisconsin (UWM), and pursued Postdoctoral fellowship at Lawrence Berkeley National Lab, University of California Berkeley.

Prof. Seeram Ramakrishna, FREng is the Chair of Circular Economy Taskforce at the National University of Singapore (NUS). He is a member of the Enterprise Singapore National Mirror Committee (NMC) on ISO/TC323 for Circular Economy. He is an advisor to the Singapore National Environmental Agency’s CESS events. He is a member of the World Economic Forum (WEF) Committee on Future of Production Sustainability. He is the Editor-in-Chief of Springer Nature Journal Materials Circular Economy. He is an editorial board member of NATURE Scientific Reports. He is a co-organizer of the NSF, USA sponsored conference on materials and circular economy and sustainability ( He chairs the Future of Manufacturing Group, Institution of Engineers Singapore. His leadership roles include NUS University Vice-President (Research Strategy); Dean of NUS Faculty of Engineering; Director of NUS Enterprise; and Founding Chairman of Solar Energy Research Institute of Singapore, SERIS. He is an elected Fellow of UK Royal Academy of Engineering (FREng); Singapore Academy of Engineering; Indian National Academy of Engineering; and ASEAN Academy of Engineering & Technology. He received PhD from the University of Cambridge, UK and the TGMP from the Harvard University, USA. He is named among the World’s Most Influential Minds and the Top 1% Highly Cited Researchers in Materials Science by Thomson Reuters and Clarivate Analytics. A European study placed him among the only 500 researchers with H index above 144 in the history of science and technology (


  • Balabanic D, Rupnik M, Klemencic AK (2011) Negative Impact of Endocrine-disrupting Compounds on Human Reproductive Health. Reproduction, Fertility and Development 23(3):403{416
  • Bisinella V, Albizzati PF, Astrup TF, Damgaard A, Life Cycle Assessment of grocery carrier bags
  • Cao G, Zhang X, Zheng F (2006) Inventory of Black Carbon and Organic Carbon Emissions from China. Atmospheric Environment 40(34):6516{6527
  • Chandrappa R, Das DB (2012) SolidWaste Management: Principles and Practice. Springer Science & Business Media
  • Chen X, Geng Y, Fujita T (2010) An Overview of Municipal Solid Waste Management in China. Waste management 30(4):716{724
  • Chen X, Li C, Grätzel M, Kostecki R, Mao SS (2012) Nanomaterials for Renewable Energy Production and Storage. Chemical Society Reviews 41(23):7909{7937
  • Dhakal S (2009) Urban Energy Use and Carbon Emissions from Cities in China and Policy Implications. Energy policy 37(11):4208{4219
  • EIU (2009) European Green City Index: Assessing the environmental impact of Europes major cities, Sponsored by Siemens
  • EIU (2012) The green city index. a summary of the green city index research series. URL: https://www international/all/en/pdf/gci report summary pdf (accessed 24/03/2016)
  • EMA-Singapore, Piped Natural Gas and Liquefied Natural Gas., [Online; accessed 25-September-2019]
  • Finnveden G, Hauschild MZ, Ekvall T, Guinee J, Heijungs R, Hellweg S, Koehler A, Pennington D, Suh S (2009) Recent Developments in Life Cycle Assessment. Journal of environmental management 91(1):1{21
  • Gollin D, Jedwab R, Vollrath D (2016) Urbanization with and without Industrialization. Journal of Economic Growth 21(1):35{70
  • Guinee JB (2002) Handbook on Life Cycle Assessment Operational Guide to the ISO Standards. The international journal of life cycle assessment 7(5):311{313
  • Hales M, Pena AM, Peterson E, Dessibourg-Freer NM, Wang J, Chen P, Zhou P (2019) A Question of Talent: How Human Capital Will Determine the Next Global Leaders; 2019 Global Cities Report by A.T.Kearney
  • Ibrahim RK, Hayyan M, AlSaadi MA, Hayyan A, Ibrahim S (2016) Environmental Application
  • of Nanotechnology: Air, Soil, and Water. Environmental Science and Pollution Research 23(14):13754{13788
  • ICLEI-USA, NYC Solid Waste, In association with The Mayors Oce of Long-Term Planning and Sustainability, City of New York., [Online; accessed 25-September-2019]
  • Jain SK (2011) Population Rise and Growing Water Scarcity in India { Revised Estimates and Required Initiatives. Curr Sci 101(3):271{276
  • Kaza S, Yao LC, Bhada-Tata P, Van Woerden F, What a Waste 2.0: A Global Snapshot of Solid Waste Management to 2050.Urban Development; Washington DC: World Bank., [Online; accessed 25-September-2019]
  • Kloeper W (2008) Life Cycle Sustainability Assessment of Products. The International Journal of Life Cycle Assessment 13(2):89
  • Korhonen J, Honkasalo A, Seppälä J (2018) Circular Economy: The Concept and its Limitations. Ecological economics 143:37{46
  • Lee J, Mahendra S, Alvarez PJ (2010) Nanomaterials in the Construction Industry: A Review of their Applications and Environmental Health and Safety Considerations. ACS nano 4(7):3580{3590
  • MacWhinney R, Klagsbald O, Inventory of New York City Greenhouse Gas Emissions in 2015, New York City Mayors Oce of Sustainability., [Online; accessed 25-September-2019]
  • Mao SS, Chen X (2007) Selected Nanotechnologies for Renewable Energy Applications. International journal of energy research 31(6-7):619{636
  • Massaad C, Entezami F, Massade L, Benahmed M, Olivennes F, Barouki R, Hamamah S (2002) How Can Chemical Compounds Alter Human Fertility? European Journal of Obstetrics & Gynecology and Reproductive Biology 100(2):127{137
  • MEWR-Singapore, Semakau Landfill: Limited Waste for Our Growing Amount of Waste., [Online; accessed 25-September-2019]
  • Murray A, Skene K, Haynes K (2017) The Circular Economy: An Interdisciplinary Exploration of the Concept and Application in a Global Context. Journal of Business Ethics 140(3):369{380
  • Narayana T (2009) Municipal Solid Waste Management in India: From Waste Disposal to Recovery of Resources? Waste management 29(3):1163{1166
  • Nascimento DLM, Alencastro V, Quelhas OLG, Caiado RGG, Garza-Reyes JA, Rocha-Lona L, Tortorella G (2019) Exploring Industry 4.0 technologies to enable circular economy practices in a manufacturing context: A business model proposal. Journal of Manufacturing Technology Management 30(3):607{627
  • NCCS-Singapore (2012) Climate Change & Singapore: Challenges. Opportunities. Partnerships. pp 1{140
  • NEA-Singapore, Waste Management: Waste Statistics and Overall Recycling., [Online; accessed 25-September-2019]
  • PACE, The Circularity Gap Report – Circle Economy
  • PACE, WEF, Strategy A, Harnessing the Fourth Industrial Revolution for the Circular Economy Consumer Electronics and Plastics Packaging
  • Poongothai J, Gopenath T, Manonayaki S (2009) Genetics of Human Male Infertility. Singapore Med J 50(4):336{347
  • Qu X, Alvarez PJ, Li Q (2013) Applications of Nanotechnology in Water and Wastewater Treatment. Water Research 47(12):3931{3946
  • Ramachandra T, Sreejith K, Bharath H (2014) Sector-wise Assessment of Carbon-footprint Across Major Cities in India. In: Assessment of Carbon Footprint in Different Industrial Sectors, Volume 2, Springer, pp 207{267
  • Satterthwaite D (2008) Cities’ Contribution to Global Warming: Notes on the Allocation of Greenhouse Gas Emissions. Environment and urbanization 20(2):539{549
  • Serrano E, Rus G, Garcia-Martinez J (2009) Nanotechnology for Sustainable Energy. Renewable and Sustainable Energy Reviews 13(9):2373{2384
  • Sharholy M, Ahmad K, Mahmood G, Trivedi R (2008) Municipal SolidWaste Management in Indian Cities { A Review. Waste management 28(2):459{467
  • Theron J, Walker J, Cloete T (2008) Nanotechnology and Water Treatment: Applications and Emerging Opportunities. Critical reviews in microbiology 34(1):43{69
  • Tsutsumi O (2005) Assessment of Human Contamination of Estrogenic Endocrine-disrupting Chemicals and their Risk for Human Reproduction. The Journal of steroid biochemistry and molecular biology 93(2-5):325{330
  • UNDP, Goal 11: Sustainable cities and communities., [Online; accessed25-September-2019]
  • UNDP, Goal 13: Climate Action., [Online; accessed 25-September-2019]
  • UNDP, Goal 14: Life Below Water., [Online; accessed 25-September-2019]
  • UNDP, Goal 15: Life on Land., [Online; accessed 25-September-2019]
  • UNDP, Goal 6: Clean Water and Sanitation., [Online; accessed 25-September-2019]
  • UNDP, Goal 7: Affordable and Clean Energy. html, [Online; accessed 25-September-2019]
  • UNDP, Goal 8: Decent Work and economic Growth., [Online; accessed 25-September-2019]
  • Varghese OK, PauloseM, Grimes CA (2009) Long Vertically Aligned Titania Nanotubes on Transparent Conducting Oxide for Highly Efficient Solar Cells. Nature nanotechnology 4(9):592
  • Varma RS (2012) Greener approach to nanomaterials and their sustainable applications. Current Opinion in Chemical Engineering 1(2):123{128
  • Victor K (2018) How Long Have Humans Been On Earth?, World Atlas [Online; accessed 25-September-2019]
  • Zhang DQ, Tan SK, Gersberg RM (2010) Municipal Solid Waste Management in China: Status, Problems and Challenges. Journal of environmental management 91(8):1623{1633
  • Zhang XP, Cheng XM (2009) Energy Consumption, Carbon Emissions, and Economic Growth in China. Ecological Economics 68(10):2706{2712


Please enter your comment!
Please enter your name here