The future does not have to be disposable. What if the materials in an old building did not become demolition waste, but the walls, doors, windows, bricks, steel beams, and flooring of the next one? What if food waste became compost, rainwater became a resource, excess heat warmed neighboring buildings, and valuable metals contained in discarded electronics were recovered for new products?
This is the basic idea of a circular economy: instead of extracting resources, using them once, and discarding them, we keep resources in circulation for as long as possible. Every resource should have a next life through reuse, repair, recycling, recovery, or regeneration.
Why: Moving Beyond Take-Make-Waste
For generations, economic growth has largely followed a linear model: take resources from nature, make products, use them, and eventually throw them away. This “take-make-waste” approach consumes finite resources while generating enormous quantities of waste.
Despite years of discussion about recycling and resource efficiency, the global economy remains overwhelmingly linear. The Circularity Gap Report 2026 refers to the latest global Circularity Metric of just 6.9%. In other words, 93.1% of materials entering the global economy still come from virgin sources rather than secondary materials.[1]
The economic potential is enormous as well. It is estimated that the global economy loses €25.4 trillion in avoidable economic value every year through inefficient material use, energy and food losses, end-of-life waste, and deterioration of assets – equivalent to almost 31% of global GDP.[2]
A circular economy seeks to change this by keeping products, components, and materials useful for longer, ideally within local or regional cycles. This shortens supply chains and transportation distances. Circularity is therefore about much more than recycling: it begins with using less, using longer, repairing, sharing, and reusing wherever possible.
When: The Circular Transition Is Happening Now
The circular economy does not have to wait for a distant technological breakthrough. Many of its principles can already be applied today. The transition toward renewable energy, decentralization, and more localized economies creates opportunities to rethink how cities obtain and use resources.
Cities are particularly important. Buildings, households, businesses, transportation, food, water, and energy create enormous flows of resources. Closing more of these loops locally can turn cities from places that primarily consume resources into places where resources are continually reused, recovered, and regenerated.
The timing matters because decisions made today determine resource demand for decades. According to UNEP and GlobalABC, around half of the buildings that will exist in 2050 have yet to be built.[3] This is particularly relevant in rapidly growing countries like Nigeria, which is projected to reach around 376 million people by 2054.[4] Providing homes and infrastructure for growing populations makes circular construction, material reuse, and resource efficiency increasingly important. How we build, retain, renovate, and reuse buildings today will therefore have long-term consequences.
How: Closing the Loops
So how does a circular economy work? Fundamentally, it replaces one-way resource flows with loops. Before producing something new, we ask whether what already exists can continue to be used. Products can be maintained and repaired, buildings renovated instead of demolished, and components removed and reused elsewhere. If direct reuse is no longer possible, materials can be recovered and returned to production. Water, nutrients, and energy can similarly be captured and circulated instead of discarded.
Technology can support these loops through digital product passports, material databases, and transparent supply chains that show what materials exist, where they are, and how they can be reused. The principle is straightforward: preserve as much existing value as possible before investing resources and energy in creating something new.
What: Giving Buildings and Materials a Next Life
Construction provides one of the clearest examples. When a building is renovated or dismantled, many of its components may still be perfectly usable. Doors can become doors again. Windows can be removed and installed elsewhere. Bricks, roof tiles, flooring, timber, steel elements, and sanitary fixtures can be salvaged and incorporated into new projects.
Even entire structures can sometimes be retained. Existing walls, foundations, facades, and structural elements can become the starting point for a new use instead of being demolished and replaced.
The potential is huge, since buildings and construction account for around 37% of global CO2 emissions and nearly 50% of global material extraction.[3]
In the European Union, construction and demolition waste accounts for more than one-third of all waste generated. Rather than seeing an old building simply as something to demolish, circular thinking can turn it into a material bank.[5]
Repair and Reuse: Keeping Products in Circulation
The same principle applies to everyday products. Repair and reuse hubs can give furniture, appliances, bicycles, electronics, clothing, and tools a longer useful life. Community repair workshops, tool libraries, secondhand centers, and material exchanges can become important elements of a circular city. Cities like Portland demonstrate this through grassroots tool libraries and other community reuse and repair initiatives.
Repair is increasingly supported by legislation. Since July 2026, EU right-to-repair rules require manufacturers to offer repairs for certain products, including washing machines, vacuum cleaners, smartphones, and tablets. Repair during the legal guarantee period also extends the guarantee by at least 12 months. Spare-parts requirements further support longer product lifetimes, including up to ten years for washing machines and at least seven years after a model leaves the EU market for smartphones and tablets.[6]
Water, Nutrients, and Urban Farming
Water can circulate, too. Rainwater harvesting systems can capture water from roofs and other surfaces for irrigation and other suitable uses rather than immediately channeling it away. This connects circularity with blue-green infrastructure and sponge cities.
Organic waste represents another resource stream. Food scraps and garden waste contain nutrients that can return to the natural cycle through composting. The resulting compost supports urban farming, community gardens, parks, and other green spaces. Instead of a one-way flow of food into the city followed by waste out of it, nutrients can circulate locally again.
Energy: Recovering What Would Otherwise Be Lost
Circular thinking also applies to energy. Industrial facilities, data centers, wastewater systems, supermarkets, and other processes generate heat that would otherwise be released into the environment. Vancouver, for example, recovers heat from its sewage system.
District heating systems can capture suitable sources of excess heat and distribute it to homes, offices, and other buildings. Energy that would otherwise be lost becomes a useful resource.
Recycling and Urban Mining
A familiar example of circularity in everyday life is Germany’s deposit system for beverage containers.[7] Consumers pay a small deposit when purchasing beverages in reusable bottles, single-use plastic bottles, or aluminum cans, which is refunded when the empty container is returned. Reusable glass and plastic bottles can be cleaned and refilled many times, while single-use bottles and cans are collected for high-quality recycling, keeping valuable materials in circulation.[8]
Urban mining takes recycling a step further by treating buildings, infrastructure, electronics, and other urban stocks as valuable deposits of secondary raw materials. Cities can effectively become resource reservoirs, supplying materials for new products and construction instead of relying solely on virgin extraction.
The Potential Is Huge
The three figures mentioned already above illustrate the scale of the opportunity: buildings and construction are responsible for around 37% of global CO2 emissions and nearly 50% of global material extraction, while only 6.9% of materials entering the global economy currently come from secondary sources.[3][1] These numbers show why circularity is not a niche environmental concept. It is about fundamentally changing how we create and retain value – environmentally, socially, and economically.
Connecting the Dots with Solarpunk
This is where the circular economy and Solarpunk naturally meet. It is not only about renewable and decentralized energy, greener cities, local participation, and keeping resources in circulation. It is also about sufficiency: thinking twice before buying yet another product and recognizing that sometimes consuming less is the better choice. Solarpunk therefore also involves care and mindful consumption.
Circular economy turns the idea of waste on its head. Instead of being discarded, materials and products can be reused, repaired, repurposed, or recycled, keeping valuable resources in circulation for as long as possible. That is a fundamentally Solarpunk idea: using the resources we already have more intelligently to build a more sustainable, resilient, and resource-efficient future.
Sources:
[1] https://dashboard.circularity-gap.world/report/2026/cgr-2026-introduction
[2] https://dashboard.circularity-gap.world/report/2026/cgr-2026-overview
[3] https://www.unep.org/news-and-stories/press-release/not-yet-built-purpose-global-building-sector-emissions-still-high
[4] https://population.un.org/wpp/assets/Files/WPP2024_Summary-of-Results.pdf
[5] https://environment.ec.europa.eu/topics/waste-and-recycling/construction-and-demolition-waste_en
[6] https://commission.europa.eu/news-and-media/news/right-repair-new-consumer-rights-easy-and-attractive-repairs-2026-07-31_en
[7] https://dpg-pfandsystem.de/en/the-one-way-deposit-system/the-dpg-deposit-process.html
[8] https://dpg-pfandsystem.de/en/the-one-way-deposit-system/useful-information/notices/how-do-i-distinguish-between-single-use-or-reusable-beverage-packaging.html?utm_source=chatgpt.com
