Comparison of Electric Power Output Observed and Estimated from Floating Photovoltaic Systems: A Case Study on the Hapcheon Dam, Korea

Jangwon Suh,Yosoon Choi,Yonghae Jang

doi:10.3390/su12010276

Abstract

An interest in floating photovoltaic (PV) is growing drastically worldwide. To evaluate the feasibility of floating PV projects, an accurate estimation of electric power output (EPO) is a crucial first step. This study estimates the EPO of a floating PV system and compares it with the actual EPO observed at the Hapcheon Dam, Korea. Typical meteorological year data and system design parameters were entered into System Advisor Model (SAM) software to estimate the hourly and monthly EPOs. The monthly estimated EPOs were lower than the monthly observed EPOs. This result is ascribed to the cooling effect of the water environment on the floating PV module, which makes the floating PV efficiency higher than overland PV efficiency. Unfortunately, most commercial PV software, including the SAM, was unable to consider this effect in estimating EPO. The error results showed it was possible to estimate the monthly EPOs with an error of less than 15% (simply by simulation) and 9% (when considering the cooling effect: 110% of the estimated monthly EPOs). This indicates that the approach of using empirical results can provide more reliable estimation of EPO in the feasibility assessment stage of floating PV projects. Furthermore, it is necessary to develop simulation software dedicated to the floating PV system.

Highlights

Floating photovoltaic (PV) systems are PV systems that float on the surface of dam reservoirs, quarry lakes, irrigation canals, or tailing ponds [1]
Hourly and monthly electric power output (EPO) from the 99.36 kWp fixed-type floating PV system at the Hapcheon Dam, Korea, were estimated using System Advisor Model (SAM) software, and the results were compared with three-year average observed EPOs
These underestimations can be ascribed to the fact that the natural cooling effect of a water environment on the improvement of PV module efficiency was not considered in the SAM-based simulation

Summary

Introduction

Floating photovoltaic (PV) systems are PV systems that float on the surface of dam reservoirs, quarry lakes, irrigation canals, or tailing ponds [1]. The market for floating PV systems has drastically expanded worldwide because of their several strengths compared with PV systems installed on land. Floating PV systems obtain higher electric power output (EPO) than PV systems on land because relatively low temperature water cools the PV panels. Because floating PV arrays are installed on water, national land can be conserved and used for other purposes that enable its efficient use [2]. Unlike most PV systems on land, floating PV systems are less obtrusive since they are generally hidden from public view. There are fewer rules and regulations for structures built on bodies of water. Fifth, this approach helps to control algae and create fish-spawning environments

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Results

Conclusion