Advancements in cooling techniques for enhanced efficiency of solar photovoltaic panels: A detailed comprehensive review and innovative classification

•A detailed comprehensive review of photovoltaic panel cooling techniques.•Original classification system for cooling methods applied to photovoltaic panels.•Valuable guidance for future research and insights into improving efficiency.•Automatic spray cooling has the shortest payback period at 1.279 years.•Phase change materials have varying payback periods between 2.828 and 3.772 years.