Madrid Scientists Create Solar Cells You Can Spray On

Imagine painting solar panels onto windows, walls, or curved surfaces as easily as spraying on a coat of paint. Scientists at Madrid's Polytechnic University just made that vision real.

The research team developed two-dimensional solar cells so thin they practically lack a third dimension. Despite their paper-thin profile, these cells absorb remarkable amounts of sunlight and convert it into electricity.

The secret lies in combining different two-dimensional materials using a technique called hot-pick-up. Researchers select, collect, and deposit tiny fragments inside transparent bubbles, creating custom structures optimized for solar energy absorption.

What makes this breakthrough different is how these cells can be produced. The team is developing spray and deposition techniques that work like industrial coating processes, making large-scale production feasible and affordable.

The researchers tested their concept by simulating what would happen if they coated a Madrid skyscraper with the semi-transparent cells. The results were striking: the building could generate up to 30% of its energy needs while still allowing plenty of natural light into interior offices.

The Ripple Effect

This technology could transform how we think about renewable energy in cities. Every window, facade, and rooftop becomes a potential power source without requiring bulky traditional solar panels.

The lightweight, flexible nature of these cells means they can cover surfaces that current solar technology cannot reach. Curved architectural features, historic buildings with preservation requirements, and mobile structures all become candidates for solar power generation.

The cost advantages matter too. Scalable spray-on production could dramatically reduce the price barrier that keeps solar energy out of reach for many buildings and communities.

Multiple funding sources supported this research, including the Community of Madrid, the European Union, Spain's Ministry of Science and Innovation, and the Naturgy Foundation. Their combined investment signals confidence that this technology can move from laboratory to real-world application.

The path from research breakthrough to widespread use will take time, but the fundamental innovation is proven. Cities could soon harvest solar energy from surfaces we never thought possible, bringing clean power generation to the heart of urban environments where space is precious and energy demand is highest.