Could solar panel gel be the clever addition that makes PV systems work better in heatwaves and last up to 200% longer?

As the UK faces more frequent and intense heatwaves, a new cooling gel developed by international researchers offers a promising way to protect solar panels from overheating.

This material can lower panel temperatures by up to 14.1°C, boosting energy output by nearly 13% while extending the lifespan of solar panels by more than 200%.

By reducing the damaging effects of heat, this affordable, low-maintenance gel could help make solar power more reliable during hot spells – a growing concern as climate change pushes temperatures higher.

What is solar panel gel?

The solar PV gel is a composite made from sodium polyacrylate (a super-absorbent polymer) and lithium chloride (a hygroscopic salt).

When applied as a layer about 10 millimetres thick on the back of solar panels, it absorbs water from the air overnight and then slowly releases that water as vapour during the day.

This evaporation cools the panel surface by absorbing heat, much like sweating cools skin. In controlled laboratory settings, this composite achieved a peak cooling power of 373 watts per square meter, which remained steady at around 175 watts per square metre during daytime conditions.

How effective is solar panel gel?

The gel’s cooling cycle depends on environmental humidity and temperature changes. At night, when temperatures drop and humidity rises, the gel’s lithium chloride draws moisture from the air, swelling as it absorbs water.

During the day, sunlight heats the panel and causes the water to evaporate slowly from the gel. This evaporation process pulls heat away from the panel surface, effectively lowering its temperature.

Outdoor tests in Saudi Arabia’s hot climate showed the gel maintained a temperature reduction averaging 9.4°C over a 10-hour period, peaking at 14.1°C on hot days where ambient temperatures reached 38°C.

Because solar panel efficiency drops about 0.2 to 0.5% for every degree Celsius of temperature increase, this cooling translates to a 10.2% to 12.9% boost in power output during testing.

A key advantage is the gel’s ability to release moisture consistently over more than 10 hours.

How is the solar panel gel applied?

One of the gel’s biggest advantages is that homeowners don’t need to apply it themselves.

The material is designed to be pre-applied at the manufacturing stage or installed by trained technicians during panel installation. It forms a thin, passive layer on the rear side of the solar panel – no electronics or refilling required.

For existing systems, the gel can be retrofitted as long as it is applied carefully by qualified installers. This ensures proper contact and airflow, and avoids damaging the panel or invalidating warranties.

Once installed, the gel requires no maintenance and automatically recharges using ambient air humidity each night – making it a hands-off cooling solution for both new and existing solar systems.

Why solar panel gels could work for UK homes

While tested extensively in hot, humid climates like Saudi Arabia, the gel’s design suits temperate regions like the UK because it relies on natural nighttime humidity to recharge.

Summer nights in many UK areas often have enough moisture for the gel to absorb, especially near coasts or during typical summer weather patterns, making it suitable for when it gets too hot for solar panels.

However, researchers acknowledge that in drier or cooler climates, the gel’s efficiency may vary. Further testing is needed to confirm long-term performance under UK conditions, including typical summer temperature ranges (often between 18°C and 30°C) and humidity fluctuations.

Researchers are optimistic though that with further development and partnerships with solar manufacturers, this technology could reach the market within the next few years.

Its potential benefits include:

• Extending how long solar panels last by up to 200%
• Reducing the cost of solar panels and electricity by 18% due to improved efficiency and less frequent panel replacement
• Providing passive, zero-energy cooling without pumps or fans

If successfully commercialised, this gel could offer UK homeowners a cost-effective way to protect investments and maximise power output during heatwaves – an increasingly urgent need as the climate warms.