Minimizing storage needs for large scale photovoltaics in the urban environment

The rising popularity of PV has prompted the creation of urban community solar projects. This study evaluates the combined effect of aggregating demand, photovoltaic generation and electricity storage, on-site consumption of PV and its impact on the grid. Data sets with real aggregated electricity demand from grid distribution transformers were used and the PV potential of building façades and rooftops was estimated. The amount of PV in each orientation in the façades and rooftops was optimized maximizing self-sufficiency and minimizing net load variance. Two storage management strategies were investigated: one for maximizing self-consumption and the other to reduce net load variance. We show that the aggregation of the demand and PV potential from different building surfaces in the urban context translates into a better demand-supply match, therefore minimizing storage needs. Higher storage capacities with proper management strategy are needed for mitigation of unmanageable net load variance and consequent costs for the grid operator.