Research is exploring harvesting solar energy indoors, where light is weaker and comes mainly from artificial sources. This is especially important for the rising number of small electronic devices that need reliable, sustainable power without relying on disposable batteries.
A study shows how indoor solar technology can make a major leap forward, achieving an impressive 37.6% efficiency by introducing a new method called triple passivation.
Why Indoor Photovoltaics Matter
Indoor Photovoltaics (often shortened to IPV) are designed to capture energy from low-intensity indoor light, such as LED or fluorescent lamps. This energy can power sensors, Internet of Things (IoT) devices, and other electronics, cutting down the need for frequent battery replacement.
The challenge is efficiency. Standard solar cells, which perform well under strong sunlight, lose much of their effectiveness under weak indoor light. Improving IPV efficiency is crucial if these systems are to replace batteries at scale.
The Innovation: Triple Passivation
Passivation (in the sense of reducing defects in a solar cell’s material so that fewer charge carriers are lost) is already a known way to improve performance. The thesis introduces a new approach called triple passivation, which tackles the problem more comprehensively.
The method combines three layers of passivation that work together to minimize energy loss. This approach improves both how the solar cell absorbs light and how it transports electric charges once that light has been captured.
The Research Approach
The thesis combined experimental testing with advanced modeling to measure the impact of triple passivation on cell efficiency. It examined:
- How each layer of passivation contributes to reducing defects
- The effect on charge transport under indoor light conditions
- Overall efficiency compared with standard passivated designs
The work showed clear gains in the performance of IPV cells when triple passivation was applied.
Key Findings
- Indoor photovoltaic efficiency reached 37.6 percent — a record performance for this type of solar cell.
- Triple passivation significantly reduced recombination losses (in the sense of electrons and holes canceling each other out before generating usable current).
- The approach improves not only the energy conversion efficiency but also the stability of the devices over time.
- The technique can be integrated into existing IPV designs without requiring entirely new manufacturing processes.
Why This Matters
This work demonstrates that high-efficiency indoor photovoltaics are within reach. With triple passivation, solar cells can harvest indoor light far more effectively, making them a practical power source for billions of low-energy devices.
If scaled, this could reduce battery waste, lower maintenance costs, and help support the spread of smart technologies powered cleanly and continuously by ambient light.
The Bigger Picture
Indoor energy harvesting may not have the drama of giant offshore wind farms or desert solar arrays, but it could quietly transform how everyday electronics are powered. From health monitors to smart home sensors, the potential is vast.
This research shows that by refining solar cells at the microscopic level, big gains are possible — and that the future of renewable energy may be just as much indoors as it is outdoors.
Source
Enhancing Indoor Photovoltaic Efficiency to 37.6% Through Triple Passivation Reassembly and n-Type to p-Type Modulation in Wide Bandgap Perovskites, Adv. Functional Matter 2025, 2502152, 2025-04-30
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