BoS cost savings and LCOE reduction for a 10 MW PV system with the 500 kW transformerless inverter

Abstract

This paper presents the cost advantages that a high-performance, 500 kW, transformerless PV inverter can have for a solar PV system. Higher efficiency, smaller size, and lower installation costs impact balance-of -system (BoS) costs and reduce the levelized cost of energy (LCOE) compared with traditional, transformer-based PV inverters. These cost advantages should be considered as integrators and end-users in China and the U.S. select and install inverters in PV systems. This paper focuses on the effect of a more efficient PV inverter on BoS cost and LCOE, analyzing real PV grid-connected, transformerless inverter applications as well as unipolar and bipolar PV array configurations. Some standards and specifications for the PV inverters are introduced, such as CEC-weighted and EU efficiency. Using the Solar Advisory Model (SAM) and PVSYST software with PV module, inverter, and weather data, a simulation to calculate the LCOE and system performance rate of a bipolar PV array with a transformerless inverter is presented for a 10 MW PV system in Dunhuang, China.