MXene-based hybrid nanofluids in pulsating heat pipes: Advanced thermal management for photovoltaic efficiency enhancement and economic analysis

Efficient thermal management remains a critical limitation for photovoltaic (PV) panels operating under high solar irradiance, where temperature rises can reduce electrical efficiency by up to 0.5 % per °C. This study introduces and experimentally validates, for the first time, a dual pulsating heat pipe (PHP) cooling system employing eco-friendly MXene-based hybrid nanofluids, specifically MXene–reduced graphene oxide (MXene-rGO) and MXene–copper oxide (MXene-CuO), as advanced working media. Outdoor experiments evaluated thermal, electrical, exergy, and economic performance at low nanoparticle concentrations (0.1 and 0.2 wt%). At 0.2 wt%, MXene-rGO enhanced PV electrical efficiency by 12.1 %, exergy efficiency by 7.6 %, and reduced thermal resistance by 44 % relative to an uncooled panel. MXene-CuO achieved corresponding improvements of 8.6 % and 4.8 %, confirming strong heat transfer synergy between MXene and metal or carbon components. Economic evaluation demonstrated long-term feasibility, with a levelized cost of energy (LCOE) of 0.107 $/kWh and a net present value (NPV) of $287, indicating a favorable cost–performance balance. The proposed MXene-based PHP concept establishes a new pathway for passive and sustainable PV thermal management, offering the first integrated experimental, exergy, and techno-economic assessment of hybrid nanofluid cooling for real outdoor PV operation.