Energy performance assessment of a semi-integrated PV system in a zero emission building through periodic linear regression method

Abstract

The ZEB Living Laboratory is a pilot building and experimental facility realized within the Research Centre on Zero Emission Buildings. The building is a single-family house designed to reach the ZEB-OM target – Zero emission Buildings when emissions for operation and building materials are accounted.

The building has a semi-integrated photovoltaic (PV) plant installed over two slopes of the building’s roofs. The total installed power (DC) is approximately 12.5 kWP. Each PV roof is connected to a power inverter with a nominal AC rated power output of 4.6 kW, based on a layout that optimize energy conversion, given the fact that shading over the two roof slopes is different.

In this paper, the performance analysis of the PV system is carried out considering the six months in the first year of operation of the system. A graphical analysis based on the linear regression method is presented and the array yield is compared against the reference yield (Performance Ratio). The analysis gives a general overview of the performance of the system, and a focus is then placed on the understanding of the system’s output in relation to the undersizing of the PV inverters.