Evaluation of sound emitted from a solar energy facility equipment pad

While commercial solar energy projects typically do not generate as much sound as other energy generating facilities such as wind turbine projects and fossil-fuel power plants, the equipment that supports commercial scale solar projects - transformers and inverters - does generate sound and can be tonal. Due to the mechanics of transformers, the sound emitted when operating without fans is tonal. The tonality of inverters is less predictable. It varies depending on the manufacturer and product design. Often the manufacturer technical noise reports lack enough detailed information to properly assess tonality. Then rarely do they have data on the sound emitted at different power outputs. This paper investigates the sound emitted and the tonality of a solar energy equipment pad with a set of five inverters and one medium voltage transformer as a function of solar insolation and power output.