This document presents a novel methodology for optimizing building integrated photovoltaic (BIPV) installations. The methodology uses optimization algorithms to determine the optimal PV panel technologies, sizing, orientation, and other parameters to meet energy demand at minimum cost. It involves forecasting building energy demand, simulating PV panel performance under different conditions, maintaining a database of PV technologies and costs, and using genetic algorithms to iteratively optimize the design. The methodology is intended to provide an easy to use tool for designers, installers and other professionals to cost-effectively design BIPV installations.