A new multiunit optimization algorithm is formulated to plan participation by photovoltaic sources with significant penetration in utility generation. The focus is on the minimization of the overall levelized cost of energy, with constraints on demand, capacity as decided by penetration, efficiency levels, and various cost components. Collector areas, unit ratings, and required investment evolve as part of the plan. A case study involving a utility service area, inclusive of 12 potential installation sites, is used to illustrate features of the algorithm.