Energy community incurred grid cost redistribution mechanisms considering different objectives and aspects of fairness

Uniqueness and following individual objectives should be an integral part of energy communities (ECs). However, often-times ECs are regulated quite strictly, thus mitigating their individualism. To provide a certain degree of freedom for ECs, this study introduces three different redistribution mechanisms for EC-incurred grid costs: Income-based redistribution aims at alleviating the financial burden of low-income households, contribution-based redistribution benefits participants providing EC assets (e.g. PV system), while proximity-based redistribution rewards virtual energy flows with short distances from source to sink. The redistribution mechanisms are applied to a fictitious EC of twelve household participants, six being equipped with a rooftop PV system. All three redistribution mechanisms prove to alleviate the financial burden of some EC participants, while EC participation still remains profitable for those participants who are burdened with additional costs due to redistribution. In the case of income-based redistribution the range of additional costs for medium- and high-income households ranges between 5€ and 40€ per year. A similar maximum of additional costs can be reported in case of contribution-based redistribution. Proximity-based redistribution leads to an additional cost range of 30€ to 54€. While fairness is mostly a subjective perception, the redistribution mechanisms can be considered fair in the sense that additional financial burdens in percent are equal for households sharing certain decisive characteristics (e.g. PV system, belonging to medium- or high-income category). The proposed algorithms are not restrained for application to EC-incurred grid costs, and can be applied to other cost components that seem fit for redistribution between EC participants.