kretsløpet

Kretsloppet is a term used in Swedish to describe a process or system in which materials, energy, or nutrients circulate in repeating cycles rather than being consumed or wasted. The word combines krets, meaning cycle or circuit, with lopp, meaning loop, and it is often used in discussions of sustainability, biology, and technology. In general use, kretsloppet denotes a closed or near-closed loop where outputs from one step become inputs for another.

In biology and physiology, the concept appears in descriptions of metabolic or signaling cycles within organisms, where intermediates are regenerated and recycled to sustain function. In ecology and environmental science, kretsloppet is central to nutrient cycles and energy flow in ecosystems, illustrating how matter and energy move through organisms, detritus, soil, and atmosphere.

In engineering, industry, and policy, kretsloppet is applied to the idea of a circular economy: products and materials are designed for reuse, remanufacturing, or recycling, so that resources stay in productive use and waste is minimized. This framing supports strategies such as industrial symbiosis, material recovery, and life-cycle thinking.

Variations of the term appear in educational materials, municipal programs, and corporate sustainability reports. While not tied to a single discipline, kretsloppet as an idea emphasizes feedback, regeneration, and continuity across systems.

See also: circular economy, nutrient cycle, metabolic cycle, closed-loop system, life-cycle assessment.