Performance and Economics of Solar Inverters and Module Level Power Electronics in a 1 MW Photovoltaic System

Photovoltaic solar panels convert sunlight to electricity in the form of direct current; therefore, a necessary component of every photovoltaic system is an inverter to convert the electricity to usable alternating current. There are various commercially available inverter technologies manufactured today such as microinverters, string inverters, and central inverters, as well as module level power electronic devices such as DC optimizers that are capable of improving system performance in string and central inverter systems. This thesis compares the performance and economics of five different inverter and module level power electronic systems through model simulation using Helioscope software. The five alternatives tested were Enphase microinverter, SMA string inverter, SolarEdge string inverter with DC optimizer, ABB central inverter, and ABB central inverter with DC optimizer. Each system was optimized for a 1 MW photovoltaic system located in Fayetteville, AR. The best alternative proved to be the SolarEdge string inverter with DC optimizer system which produced the highest annual energy generation of 1,551,043 kWh and provided substantial economic benefit. The SolarEdge alternative just outperformed the microinverter alternative by nearly 10,000 kWh annually and showed a significantly greater economic benefit of the 25-year lifetime of the system. The SMA string inverter demonstrated a nearly identical economic benefit, although slightly higher, compared to the SolarEdge DC optimizer system but was outperformed in energy output by nearly 40,000 kWh annually. Both central inverter alternatives did not prove to be viable options due to high capital cost