Microbial breakdown of organic matter in the absence of oxygen.

In a circular economy, anaerobic digestion can be used to convert food by-products, sewage sludge, and other biodegradable materials into digestates (or ‘biosolids’) that can be used as soil enhancers and biogas.

The processes - such as composting and anaerobic digestion - that together help to regenerate natural capital. The only materials suitable for these processes are those that can be safely returned to the biosphere.

A systems solution framework that tackles global challenges like climate change, biodiversity loss, waste, and pollution. It is based on three principles, driven by design: eliminate waste and pollution, circulate products and materials (at their highest value), and regenerate nature.

It is underpinned by a transition to renewable energy and materials. Transitioning to a circular economy entails decoupling economic activity from the consumption of finite resources. This represents a systemic shift that builds long-term resilience, generates business and economic opportunities, and provides environmental and societal benefits.

Microbial breakdown of organic matter in the presence of oxygen.

In a circular economy, composting can be used to convert food by-products and other biodegradable materials into compost, which can be used as a soil enhancer.

The ability of a product, component or material to remain functional and relevant when used as intended.

Durability often applies to the physical attributes of a product (its ability to resist damage and wear), though with some products durability can be technological (for example the ability of software to be upgraded many times), and it can be emotional (for example the ability of certain clothes to stay desirable over time).

Materials that are non-renewable on timescales relevant
to the economy, i.e. not geological timescales.

Examples include: metals and minerals; fossil forms of carbon such as oil, coal, and natural gas; and sand, rocks, and stones.

The period of time from when a product is released for use after manufacture to the moment it becomes obsolete beyond recovery at product level.

An economy in which finite resources are extracted to make products that are used - generally not to their full potential - and then thrown away (‘take-make-waste’)

It is a wasteful and polluting system that degrades natural systems

Keep a product in its existing state of quality, functionally and/or cosmetically, to guard against failure or decline.
It is a practice that retains the highest value of a product by extending its use period.

Materials that have been previously used.

This includes: materials in products that have been reused, refurbished or repaired; components that have been remanufactured; materials that have been recycled. Also referred to as secondary materials.

The ease with which a material can be recycled in practice and at scale.

Transform a product or component into its basic materials or substances and reprocess them into new materials.
Embedded energy and value are lost in the process. In a circular economy, recycling is the last resort action.

Divert a product from its intended market
to another customer so it is used at high value instead of becoming waste.

For example, a supermarket can redistribute surplus edible food to a food-bank.

Return a product to good working order. This can include repairing or replacing components, updating specifications, and improving cosmetic appearance.

Regenerative production provides food and materials in ways that support positive outcomes for nature, which include but are not limited to: healthy and stable soils, improved local biodiversity, improved air and water quality.

In agriculture, regenerative production schools of thought include agroecology, agroforestry, and conservation agriculture.

Re-engineer products and components to as-new condition with the same, or improved, level of performance as a newly manufactured one.

Remanufactured products or components are typically provided with a warranty that is equivalent to or better
than that of the newly manufactured product

Energy derived from resources that are not depleted on timescales relevant to the economy, i.e. not geological timescales.

Examples include: wind, solar, hydropower, hydrothermal, ocean (wave and tidal), geothermal, and biogas from anaerobic digestion.

Materials that are continually replenished at a rate equal to or greater than the rate of depletion.

Examples include: cotton, hemp, maize, wood, wool, leather, agricultural by-products, nitrogen, carbon dioxide, and sea salt. To fit in a circular economy such materials (where relevant) must be produced using regenerative production practices.

Operation by which a faulty or broken product or component is returned back to a usable state to fulfil its intended use.

The ease with which a product or component can
be repaired.

The repeated use of a product or component for its intended purpose without significant modification.

Small adjustments and cleaning of the component or product may be necessary to prepare for the next use.

Supply chains dedicated to the reverse flow of products and materials for the purpose of maintenance, repair, reuse, refurbishment, remanufacture, recycling, or regenerating natural systems.

The use of a product by multiple users. It is a practice that retains the highest value of a product by extending its use period.

The processes that products and materials flow through in order to maintain their highest possible value at all times. Materials suitable for these processes are those that are not consumed during use - such as metals, plastics and wood.

In the technical cycle the opportunities to maintain and generate value come through retaining the greatest proportion of the energy and labour embedded in the product. This is achieved, in order of value, by: maintaining, prolonging, sharing; reusing and redistributing; refurbishing and remanufacturing; and recycling.

Materials that have not yet been used in the economy.

These include both finite materials (e.g. iron ore mined from the ground) and renewable resources (e.g. newly
produced cotton).