Industry shows an increasing interest in the circular economy. However, circularity for physical capital assets is still ill-defined and existing models are complex and information dependent hindering implementation. This paper addresses these gaps by operationalizing circular economy principles and developing a suitable business case framework embedding circularity. Following the Design Science Methodology, a framework was developed based on circularity and investment decision-making literature and requirements from a Dutch electricity grid operator. An initial evaluation showed that the framework supports selecting the preferred circular investment scenario and can be generalized to other industries.