Optimized power dispatch for solar photovoltaic -storage system with multiple buildings in bilateral contracts

Storage coupled solar photovoltaic systems have gained traction in recent years due to a) advancements in battery storage technologies and b) decreasing system costs. The viability and optimum operation of these systems is typically studied for building(s) in isolation or with grid interactions. In this paper a grid-interactive photovoltaic-storage system in a multi building scenario with net-metering is evaluated. A simulation model is developed for an interconnected multi building environment with a primary building owning the photovoltaic- battery system. The optimization model is formulated as a mixed integer linear programming problem and is solved in ILOG optimization studio with CPLEX solver. Multiple secondary buildings can procure power from the primary building based on suitable bilateral contracts. The applicability of the model is demonstrated through real-time load demand of three buildings along with actual time-of-use pricing data from the utility in the city of Auckland, New Zealand. The results provide an insight on the financial gains of installing rooftop photovoltaic- battery systems at buildings with power trading agreements under time-varying electricity tariffs. The detailed results from the model signify that primary building (with solar and storage) earns up to 43% of annual profits after incorporating installation costs of photovoltaic-battery system. Further, secondary buildings (without solar or storage) achieve 3-16% of savings in the electricity costs based on different contracted loads and agreement tariffs. This work can further enhance the utilization of solar energy resource via rooftop solar photovoltaic to help mitigate the per capita carbon dioxide emissions in countries with high dependency over fossil fuel for electricity generation.