An Assessment of Traditional and Ensemble Evaporation Models with Implications for Floating Photovoltaic Systems in Northern Cyprus

Youssef Kassem; Huseyin Gokcekus; Abdalla Hamada Abdelnaby Abdelnaby; Hasan Yesilyuz

doi:10.48084/etasr.17322

Authors

Youssef Kassem Department of Mechanical Engineering, Engineering Faculty, Near East University, Nicosia (via Mersin 10, Turkiye), Cyprus | Energy, Environment, and Water Research Center, Near East University, Nicosia (via Mersin 10, Turkiye), Cyprus
Huseyin Gokcekus Department of Civil Engineering, Civil and Environmental Engineering Faculty, Near East University, Nicosia (via Mersin 10, Turkiye), Cyprus | Energy, Environment, and Water Research Center, Near East University, Nicosia (via Mersin 10, Turkiye), Cyprus
Abdalla Hamada Abdelnaby Abdelnaby Department of Civil Engineering, Civil and Environmental Engineering Faculty, Near East University, Nicosia (via Mersin 10, Turkiye), Cyprus
Hasan Yesilyuz Department of Civil Engineering, Civil and Environmental Engineering Faculty, Near East University, Nicosia (via Mersin 10, Turkiye), Cyprus

Volume: 16 | Issue: 2 | Pages: 34647-34657 | April 2026 | https://doi.org/10.48084/etasr.17322

Received: 3 January 2026 | Revised: 28 January 2026 | Accepted: 11 February 2026 | Online: 4 April 2026

Corresponding author: Youssef Kassem

Abstract

Accurate estimation of evaporation from open water bodies is crucial for sustainable water and energy management, given pronounced seasonal variability and water scarcity. Therefore, the evaporation rate and the performance of seven traditional evaporation estimation models and three ensemble models are assessed at different locations in Northern Cyprus. The results show that the monthly observed evaporation values range from 52.7 to 250 mm. Moreover, it is found that while all methods follow the seasonal pattern of evaporation, there are large differences among them in magnitude. The Penman series models tend to overestimate evaporation, particularly in summer, whereas simpler temperature- and radiation-based methods underestimate peak values. Bayesian Model Averaging (BMA) achieves the best performance, yielding R² values of up to 0.997 and reducing RMSE by 30%-45% across ensemble models. Furthermore, the current study aims to assess the techno-economic and environmental viability of small-scale Floating Photovoltaic (FPV) systems on the lakes at Near East University. The results show that higher surface coverage and East-West (E-W) oriented bifacial panel configurations maximize energy generation and improve economic performance while significantly reducing CO₂ emissions. Consequently, a promising avenue for FPV systems toward integrated water-energy sustainability solutions is highlighted.

Keywords:

evaporation, ensemble approaches, floating PV system, water-energy sustainability solution

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