Cooling Solar Modules with Nanofluids Based on Graphene Oxide, Mxene

Why It Matters

The pump‑free cooling approach materially lifts solar output while keeping levelized costs low, making dense urban PV installations more economically viable.

Key Takeaways

• 3D-OHP + GO‑MXene fluid cuts PV temperature >24 °C.
• Power output rose 14.9% to 48.3 W, efficiency 11.51%.
• Hybrid nanofluid stable despite 31% viscosity increase.
• LCOE $0.083/kWh and LCOS $0.273/kWh remain competitive.
• Multi‑unit OHP scaling under study for larger arrays.

Pulse Analysis

Urban solar installations face a persistent efficiency penalty as module temperatures climb under high irradiance. Traditional active cooling—fans or liquid pumps—adds capital and operational costs that erode the financial case for dense rooftop or façade arrays. Nanofluids, especially those leveraging two‑dimensional materials like MXene, have emerged as a promising passive alternative because of their high thermal conductivity and tunable optical properties. When paired with a three‑dimensional oscillating heat pipe, the fluid can transport heat without external power, offering a sleek, maintenance‑free solution for hot‑climate markets.

The recent experiment attached a copper‑based 3D‑OHP to a 50‑W PV module and circulated hybrid GO‑MXene nanofluid at 0.1–0.2 wt% concentrations. Under real‑world solar irradiance of 660‑1,090 W/m², the system lowered module temperature by more than 24 °C, translating into a 14.9% increase in generated power and pushing efficiency from 10.02% to 11.51%. Even with a 31% rise in viscosity, the fluid maintained stability, delivering an exergy efficiency of 30.9% and achieving a levelized cost of electricity of $0.083/kWh—well within competitive thresholds for utility‑scale solar.

If the multi‑unit OHP concept scales, developers could retrofit existing rooftop farms or embed cooling loops into new building‑integrated photovoltaics, reducing the need for oversized arrays to meet output targets. Coupling this passive cooling with battery storage could further improve dispatchability, lowering the levelized cost of storage to $0.273/kWh. As cities push for higher renewable penetration, such low‑maintenance, cost‑effective cooling technologies may become a differentiator, accelerating the adoption of high‑density solar in hot, densely populated regions.