Work

A 66-year assessment of photovoltaic solar resource trends across Yemen

Year: 2025

Type: article

Abstract: Yemen’s rapidly warming climate poses critical challenges to solar energy efficiency despite abundant irradiance. We observe pronounced warming across all thermal indices, with mean surface air temperatures rising by +0.25°C per decade ( p < 0.001), accompanied by increases in maximum (+0.21°C/decade) and minimum (+0.28°C/decade) temperatures for the period 1958 to 2024. Photovoltaic (PV) cell operating temperatures mirror this trend, climbing by +0.26°C/decade. We further found cumulative efficiency losses of 0.4 - 0.5% per°C for crystalline silicon PV modules, compounding Yemen’s energy vulnerabilities. Counterintuitively, downwelling surface solar radiation (SRAD) remains stable with a near-zero trend (slope ≈ -0.00 W/m² yr -1 ), while declining wind speeds of -0.002 ms yr -1 reduce natural cooling of PV modules. Our spatiotemporal analysis reveals stark regional contrasts whereby coastal zones exhibit stable or increasing PV resource potential (PVres; +0.10 W/m²/year), while inland deserts like the Rub’ al Khali margins show declines of up to -0.10 W/m²/year, likely driven by intensifying dust aerosols and land degradation. Nationally, PVres shows no significant long-term trend (-0.043 W/m²/year, p = 0.070), obscuring these critical regional vulnerabilities. Seasonal extremes ranging from April peaks of 264 W/m² to December troughs of 201 W/m² highlight the necessity for adaptive energy storage systems. We identify a critical paradox wherein nationally stable solar resources mask spatially divergent risks requiring high-resolution energy planning. Coastal regions emerge as optimal for PV deployment, whereas inland areas necessitate dust-resilient technologies and hybrid systems. We recommend that policymakers and development partners implement region-specific strategies combining coastal PV expansion with inland adaptive measures to mitigate efficiency losses.

Source: Solar Energy Advances

DOI: 10.1016/j.seja.2025.100113

Authors: Hussein Gadain, Brigadier Libanda

Institution: Food and Agriculture Organization of the United Nations

Language: English

Topic: Solar Radiation and Photovoltaics

Subfield: Artificial Intelligence

Field: Computer Science

Domain: Physical Sciences

SDGs: Climate action, Affordable and clean energy, Industry, innovation and infrastructure

Open Access status: gold

Estimated APC paid: $2,750