Mercedes-Benz Solar Paint could transform electric vehicle energy generation

Mercedes-Benz is developing an innovative photovoltaic coating that is incorporated into a car’s paintwork and could reshape how electric vehicles generate and use energy. Unveiled on the Vision Iconic prototype, the technology turns the entire bodywork into a vast photovoltaic panel, collecting energy directly for the electrical system’s battery.

Its operating principle resembles that of conventional photovoltaic cells, but at a microscopic thickness of just five micrometres. That makes it around 20 times thinner than a human hair, while its weight is only 50 g/m².

Despite being exceptionally thin and light, Mercedes claims an efficiency of more than 20%. This is an impressive figure for a flexible coating that can be applied to curved surfaces and across different materials. The manufacturer has released a video demonstrating how the system works.

How Mercedes-Benz Solar Paint generates electricity

Solar Paint is based on semiconductor nanoparticles suspended in a transparent alloy. These particles capture photons from sunlight and release electrons, creating an electrical current in the same way as conventional solar panels.

Microconductors built into the paint carry that electricity directly to the high-voltage battery, removing the need for an additional storage unit. This technical feature simplifies the setup and reduces conversion losses.

Another innovation lies in its light transmission capability. Around 94% of solar energy passes through the pigmented layers before reaching the active photovoltaic layer. As a result, the technology can be used with any colour without reducing its energy efficiency. In other words, it neither prevents nor restricts customisation options, and it does not undermine the durability of more conventional finishes.

Effective results

The technology remains under development, but Mercedes-Benz says that a vehicle with roughly 11 m² of usable bodywork area could gain about 12,000 km of additional annual range in Stuttgart.

The benefit could be even greater in cities with more sunlight. In Beijing, for instance, the figure could rise to 14,000 km, while in Los Angeles it could reach as much as 20,000 km. This would happen even when the vehicle is switched off, making better daily use of available sunlight.

The coating is also free from silicon and rare earths, two of the photovoltaic industry’s most critical materials. This improves sustainability and lowers the environmental footprint of manufacturing each car, while also making recycling easier at the end of the vehicle’s life.

Energy efficiency and direct integration with the electrical system

Fully integrating the system into the vehicle’s high-voltage circuit removes redundant components and limits electrical losses, enabling solar energy to be converted directly into usable power.

This method can power both auxiliary systems - climate control, sensors and communications - and the electric motor itself, cutting the energy required from external charging.

With this technology, Mercedes-Benz moves closer to the idea of an energy self-sufficient car by converting sunlight into the “fuel” it needs to travel. It does mean leaving the car outdoors at all times and “praying” for plenty of sunshine.