Solar energy is one of the most promising sources of clean and renewable energy. Conventional solar panels, however, are generally rigid, heavy, and require strong supporting structures. This limits their use in applications where weight, flexibility, and portability are important. Researchers at the Massachusetts Institute of Technology (MIT) have developed an innovative approach using ultrathin solar cells that are lightweight, flexible, and capable of being integrated with different surfaces.
The MIT researchers developed solar cells that are approximately 15 micrometers thick, making them much thinner than conventional photovoltaic panels. The cells can be attached to a lightweight and strong fabric, creating a flexible solar module. According to MIT, the technology can produce approximately 730 watts per kilogram when freestanding and about 370 watts per kilogram when integrated with Dyneema fabric. This demonstrates the exceptionally high power-to-weight ratio of the technology.
A significant feature of the technology is its manufacturing process. The researchers use printable electronic inks containing semiconductor materials and deposit them onto a thin substrate using a process called slot-die coating. An electrode is subsequently deposited using screen printing. After fabrication, the solar device can be separated from the temporary substrate and attached to a supporting fabric. This approach makes the photovoltaic material extremely thin while retaining its ability to generate electricity.
The lightweight nature of these solar cells opens up several potential applications. They could be incorporated into building surfaces, tents, emergency shelters, vehicle surfaces, boats, and portable equipment. For example, solar cells integrated into the fabric of a temporary shelter could provide electricity in remote locations or during disaster-relief operations. Similarly, solar-powered materials could potentially be incorporated into drone wings, where reducing weight is particularly important.
The technology also has potential for large-scale solar installations. Conventional solar panels require considerable structural support because of their weight. Lightweight photovoltaic materials could reduce the structural requirements for some installations. MIT researchers estimated that an ultralight photovoltaic system could potentially generate several kilowatts of electricity while adding only a small amount of weight to a roof.
Durability is another important consideration. In testing, the flexible solar material was repeatedly rolled and unrolled more than 500 times and retained more than 90 percent of its original performance. This indicates that the technology has promising mechanical flexibility, although further development is required for long-term outdoor applications.
Despite its advantages, challenges remain. The photovoltaic materials require protection from moisture and oxygen, which can affect their performance. Developing extremely thin protective coatings without adding significant weight is therefore an important area of ongoing research.
Paper-thin solar cells represent a significant step toward integrating renewable energy into everyday objects and structures. Rather than relying exclusively on conventional solar panels, future photovoltaic technology could become part of fabrics, buildings, vehicles, and portable systems. With continued improvements in durability, protection, efficiency, and manufacturing, ultrathin solar cells could help expand the possibilities of solar power and transform previously unused surfaces into potential sources of clean electricity.