Solar Panels Run Cooler With Simple Seawater Layer

Imagine making solar panels work better with just a shallow puddle of seawater on top.

Researchers at the Indian Institute of Petroleum and Energy have cracked one of solar power's toughest problems with a solution so simple it almost seems obvious. Heat makes solar panels less efficient, often when the sun is shining its brightest and electricity demand peaks.

The team tested a passive cooling system that places a thin layer of still seawater directly on the panel's surface while keeping other components dry. No pumps, no electricity, no moving parts.

Over four days of testing, they tried different water depths to find the sweet spot. Too thick blocked sunlight, but a 5-millimeter layer (about the thickness of two pennies stacked) delivered impressive results.

The seawater layer dropped panel temperatures by up to 10 degrees Celsius compared with uncooled panels. That temperature reduction translated to an 8.9% boost in daily energy output.

"The concept is safe, economic, and has less environmental impact," corresponding author H. Sharon told PV Magazine. Traditional cooling methods often rely on pumps or full water immersion, which increases costs, energy use, and corrosion risk.

The Ripple Effect

This breakthrough could be especially valuable for coastal communities where seawater is plentiful and energy infrastructure needs upgrading. More efficient solar panels mean more clean electricity without straining power grids or requiring expensive equipment upgrades.

The technology could help accelerate solar adoption in developing regions where cost remains a barrier. Communities that once couldn't afford complex cooling systems might now access more reliable solar power.

The research team identified one challenge: salt buildup when evaporation happens too quickly can reduce performance. They're planning tests across different climates and salt concentrations to refine the system for long-term use.

Solar power already helps residents and businesses save money while reducing planet-warming pollution and improving air quality. Making panels more efficient through passive cooling could multiply those benefits without adding complexity or cost.

The study authors noted their thermal management technique "is efficient and competitive with fin and phase change material-based module thermal management strategies," highlighting the potential for large-scale applications.

Simple solutions like this one prove that breakthrough innovations don't always require cutting-edge technology—sometimes the best answer has been waiting in plain sight all along.