Blockchain-based balance settlement ledger for energy communities in open electricity markets

Sharing local co-owned photovoltaic (PV) energy in multifamily residential buildings is inefficient. Energy produced and consumed within the same building may be considered purchased energy, of which the customer must pay the purchase price, the network service fee, and taxes. As PV typically does not allow self-sufficiency in the Nordic countries, a distribution system operator is needed to provide the grid connection. Earlier solutions to this problem are focused on energy communities where an energy aggregator is responsible for the energy balance settlement. However, this does not allow the energy community members to remain in the open electricity market. This paper introduces a blockchain-based balance settlement ledger and a set of rules for energy sharing in energy communities where members participate in the open electricity market while supplied with local low-cost PV energy. This, to the authors’ knowledge, has not been previously implemented. The blockchain mitigates the need for any central entity for balance settlement and ensures fair sharing of PV energy. The existing smart meters can be used so no investments are required. The system performance is tested with simulations which show potential for increase in profitability. The self-sufficiency rate increases in our test scenario from 4.03% to 9.61%. •Efficient sharing and utilization of locally produced solar energy.•Benefits of both local solar energy and open electricity market can be obtained.•No investments needed as existing smart meters can be used.