In 1991, EPFL scientists Brian O’Regan and Michael Grätzel developed solar cells inspired by plant photosynthesis. 34 years later, the technology had reached 12% efficiency

In 1991, EPFL scientists Brian O’Regan and Michael Grätzel altered photovoltaics by mimicking nature. Their pioneering Dye-Sensitized Solar Cell paired light-absorbing dyes with nanostructured titanium dioxide, successfully replicating how plant leaves capture energy. Contrary to common belief, the technology did not take decades to cross the efficiency mark. The original prototype achieved roughly 12 percent efficiency under diffuse daylight upon release, eventually surpassing 12 percent in direct sunlight by 2012.

Today, these ambient solar cells thrive where traditional silicon panels fall short. They produce steady electrical power from low indoor light, running wireless IoT sensors and smart home hardware without standard batteries. Because printable dye solutions allow flexible, semi-transparent glass designs, architects integrate them directly into modern windows. This plant-inspired chemistry remains a crucial bridge between structural design and sustainable micro-electronics.

Rethinking Solar Power Through Photosynthesis: What are scientists borrowing from nature?

The central challenge inside a solar cell is fairly straightforward. Light must be absorbed, electrical charges must be generated, and those charges must travel to where they can be collected. Every stage affects how much electricity ultimately comes from the sunlight hitting the device.


The review focuses heavily on two parts of that process. One is light harvesting, which determines how effectively a solar cell captures incoming light. The other is electron transfer, which concerns how electrical charges move through the device.

Researchers have found inspiration in several very different organisms. Plants and photosynthetic bacteria offer clues about energy and electron movement. Other biological structures, including insect eyes, butterfly wings and rose petals, provide ideas for controlling light at a surface.

Why do leaves matter to solar technology?

Plants have been harvesting sunlight for roughly 3.5 billion years through photosynthesis. Their systems collect light and move energy toward specialized reaction centers. That makes photosynthesis an obvious source of ideas for scientists designing artificial energy converters.

Researchers are not trying to turn solar panels into artificial leaves. Instead, they are studying the underlying principles that make natural light harvesting work. Those principles can then be translated into materials and structures designed for photovoltaic devices.

The connection has already influenced solar technology. Dye-sensitized solar cells, introduced by Michael Grätzel and Brian O'Regan in 1991, were designed around concepts resembling natural photosynthesis. Their systems use a dye and semiconductor rather than the biological machinery found inside plants.

How could butterfly wings help solar cells?

Butterfly wings provide a very different kind of inspiration. Their surfaces contain tiny structures that interact with light in ways that create their familiar visual effects. Scientists can study such structures without needing to reproduce the entire wing.

The same principle applies to other natural surfaces. An insect eye or rose petal may contain a microscopic arrangement that changes how light behaves. Engineers can examine those physical structures and ask whether similar patterns could improve solar-cell surfaces.

The potential benefit is simple. If less incoming light is reflected away, more light could enter the solar-cell material. That creates another opportunity for the device to generate electrical charges and produce useful power.

Solar cells have already come a long way

The history of photovoltaics shows how dramatically the technology has changed. Alexandre Edmond Becquerel observed the photovoltaic effect in 1839 while studying the behavior of electrolytic cells under light.

More than a century later, researchers at Bell Labs developed the first silicon photovoltaic cell. In 1954, the device produced electricity with an efficiency of about 4 percent. That early achievement eventually opened the door to today's much broader solar-cell landscape.

Organic solar cells, thin-film technologies, compound semiconductors, dye-sensitized cells and perovskites have since expanded the field. The supplied review notes that organic solar cells had reached around 17 percent efficiency in the cited research, while perovskite devices had reached about 21 percent.

Why does efficiency still matter?

Solar technology has improved enormously, but efficiency remains an important engineering challenge. A solar cell receives sunlight, yet some of that energy is inevitably lost during absorption, charge movement and collection.

That is why natural structures are interesting to researchers. Even a small improvement in how a surface captures light could affect the overall performance of a device. The gains do not necessarily need to come from one dramatic invention.

Researchers instead see potential in combining several useful ideas. Better light harvesting could work alongside improved charge transport and other advances in photovoltaic materials. The final result would depend on how well those individual components function together.

Could nature-inspired solar cells reach American rooftops?

The U.S. has an obvious reason to keep improving solar technology. The supplied research notes that American electricity consumption reached 3,971 terawatt-hours in 2018. Solar energy represents one possible source for meeting part of that enormous electricity demand.

Still, a promising laboratory design is not automatically ready for commercial solar panels. Researchers must consider manufacturing, cost, durability and long-term performance before a biological idea becomes useful at large scale.

China is now far ahead of the United States in solar power capacity. IRENA data show that China had about 1,202 GW of installed solar capacity at the end of 2025, compared with 210.9 GW in the U.S. China therefore had nearly six times America’s installed capacity. The gap widened sharply in 2025, when China added roughly 415 GW of solar, while the U.S. added about 43 GW.

China’s lead is not only about building solar farms. It also dominates much of the global manufacturing chain, from wafers and cells to finished panels. The IEA estimates that China installed nearly 370 GW of solar PV in 2025, helping the country account for more than 60% of global renewable capacity growth that year. By July 2026, solar had even overtaken coal as China’s largest source of installed power capacity, although coal still produced more electricity.

The U.S. is still expanding quickly, but at a very different scale. Solar generated 296,000 GWh of utility-scale electricity in 2025, up 34% from the previous year, while small-scale solar added another 93,000 GWh. America also installed about 43 GW of new solar capacity during the year. China’s 2026 growth has slowed after its huge 2025 installation rush, but the overall numbers remain clear: China leads the world in solar deployment, while the U.S. remains one of the largest and most important solar markets.

The next stage is likely to involve translating biological structures into practical engineering designs. Researchers can study how natural surfaces manipulate light and then reproduce those physical principles using manufactured materials.

That approach could become increasingly useful as solar technologies diversify. Perovskites, organic cells and other emerging systems provide different opportunities for experimenting with surface structures and light-harvesting strategies.

There is also a broader lesson in the research. Nature does not offer engineers a single perfect blueprint. It offers countless solutions that evolved under very different conditions, each solving a particular physical problem.

That makes the natural world less like a template and more like a giant engineering reference library. The future solar panel may not resemble a butterfly wing or a leaf at all. But one small idea borrowed from either could help it capture more sunlight.