Longevity and circularity as indicators of eco-efficient resource use in the circular economy

Natural resources are limited. The circular economy is one of several different concepts that has been useful in the quest to understand how resources can be used most efficiently. It proposes that closing loops and repeatedly using resources has the potential to procure maximum eco-efficiency. To track society's progress towards a circular economy, indicators and measures are needed. The majority of these aim to capture the circularity of resource flows, yet fail to simultaneously consider the length of time for which a resource is in use. More recently, a longevity indicator has been proposed, but similarly, it fails to take into account how many times a resource is used. Both longevity and circularity are needed for sustainable resource use, but to date, no measure that combines both approaches is in use. Based on existing measures we develop and further develop indicators for both circularity and longevity that focus on the contribution that organisations and other resource users make to the sustainability of resource use. By combining both indicators we enhance their explanatory power.