The term “hosting capacity”, in the context of power systems, was first introduced in March 2004 and has since resulted in a range of applications and research. Network operators commonly use the concept to quantify the ability of their networks to accept new production and consumption. Academic research on hosting capacity took off seriously after 2010 and has resulted in thousands of publications. This paper presents a brief history of the early years of hosting capacity studies, gives an overview of the status of both applications and research, summarises the different methods and types of studies, and correlates all that with the underlying fundamental principles of the hosting capacity concept, as it was introduced in 2004. The main focus of this paper is to review and relate these methods and studies to the fundamental principles. Having a clear understanding of these fundamental principles enables a wide range of applications for hosting capacity studies with detailed methods and models. However, it also requires transparency to ensure a coherent analysis, correct interpretation of the results, and an open discussion between stakeholders. With research on hosting capacity, it is important to refer to the fundamental principles; with applications, it is important to maintain transparency and objectivity. 

This paper presents an approach to estimate the hosting capacity for distribution networks considering the impact of PV penetration at different voltage levels. The estimation and the method were selected such that the results were most suitable for distribution system planning. A time-series based method was used as it covers significant aspects needed for prioritising network reinforcement. The MV background voltage was modelled varying in time, assuming the same penetration level in the other LV networks supplied by the same MV system. The hosting capacity is defined as the maximum acceptable PV size per customer for a given PV penetration. Based on the different possible combinations of PV location, the probability of overvoltage and overloading is used as a performance index. The planning risk is used as a limit for the performance criterion. The method can be automated for a large number of networks due to using an IEC 61970-based input format. It also enables linking DSO network models to customer smart metre databases. The severity and risks of limit violations are analysed with different metrics from the time-series simulations. The change in background voltage with increasing penetration is shown to impact the results significantly. When considering it, the estimated hosting capacity was reduced by 32 %, on average.

Solar PV connections at medium voltage (MV) level can impact low voltage (LV) networks by reducing their margin for installing additional PV units. This paper presents an approach to estimate the hosting capacity of distribution networks, including an integrated model of MV-LV networks and a visualisation method for assessing the sharing of hosting capacity between voltage levels. The objective is to quantify the mutual influence of MV and LV connections and to support the planning and management of connection requests. The proposed visualisation method illustrates the trade-off between MV and LV production units, accounting for both voltage and loading limitations, and provides a good representation of how PV connections at one voltage level affect the other. Results show that the coupling between MV and LV networks significantly impacts the hosting capacity, how it can be shared, and that constraints at either level can limit future connections. The method facilitates the identification of the voltage level imposing the most significant limitations and thus also supports the assessment of where and which mitigation strategies would be more effective. Overall, the method highlights the importance of a joint assessment considering the MV-LV coupling to support informed planning decisions.