The Lokahi Apartment complex, constructed in 2010, includes large solar PV and water heating systems, designed with the intent of offsetting all the common area electricity and dwelling unit hot water heating needs with the renewable power of the sun. The modeling of renewable energy systems was not completed during the design phase, so it was unknown if the systems were performing above or below their anticipated capacity. O’Brien360 developed hourly simulations of each of the relevant building systems and loads for each of the three prototypical buildings located at the site and compared the models to the actual building utility bills. The analysis resulted in a detailed list of recommended maintenance, controls, and efficiency measures for the owner to implement.