Researchers at Binghamton University have developed a “moist-electric wallpaper” capable of harvesting electricity from indoor humidity to power small electronics. By using a series-parallel network of 1,596 generator units, the team produced roughly 3.5 volts at 38 percent humidity, which was sufficient to power a wireless keyboard in real time when paired with a capacitor.
How Moisture-Electric Generators Produce Power
The technology relies on moisture-electric generators (MEG), which convert humidity into electrical energy. While a 2015 graphene oxide study showed that chemical gradients could generate electricity from humidity, and a 2020 Nature study highlighted the use of bacterial protein nanowires, the Binghamton University team focused on managing water movement to maintain a steady current.
The device uses 2-by-2-centimeter squares of thick chromatography paper. To prevent the paper from becoming uniformly damp—which would stop power production—the researchers engineered a unidirectional transport system. Glycerol on the edges absorbs water vapor, while a polymer called polyvinylpyrrolidone (PVP) pulls that liquid toward the center. Finally, wax-treated pores allow moisture to escape as vapor, creating a one-way traffic flow that sustains the charge imbalance.
Did you know? The researchers propose that water interacting with oxygen-rich chemical groups releases mobile hydrogen ions, creating the charge imbalance that drives the current, though they have not yet directly confirmed that protons carry most of the charge.
Energy Output and Scaling Capabilities
A single generator unit produces about 0.34 volts and a peak power density of 2.2 microwatts per square centimeter of electrode at 80 percent humidity. While this is low, the system scales effectively. The researchers demonstrated that 10 units wired in series could produce about 3 volts under the same humidity conditions.
The transition from a single cell to a wall panel shows the potential for indoor energy harvesting:
| Configuration | Humidity | Voltage Output |
|---|---|---|
| Single Unit | 80% | 0.34 V |
| 10 Units (Series) | 80% | ~3 V |
| 1,596 Units (Panel) | 38% | ~3.5 V |
Humidity Management and Technical Hurdles
Beyond power generation, the system can act as a dehumidifier. In a sealed chamber, 28 units lowered relative humidity from about 75 percent to 50 percent in roughly four minutes. However, the researchers noted that room-scale measurements for humidity control only lasted 15 minutes.
Several obstacles remain before this technology reaches consumers. A 2024 Nature Reviews Materials perspective noted that the field of sustainable moisture energy described the field as promising but highlighted low energy productivity and lingering uncertainty about its mechanisms. Specifically, the Binghamton prototype uses laboratory chromatography paper with unknown long-term durability, and there is a risk that glycerol may migrate inward over days or weeks and blur the carefully engineered zones.
Pro Tip: For those tracking sustainable tech, look for developments in “printed arrays.” A 2023 Joule study demonstrated fully printed arrays of planar moisture generators, suggesting that the manufacturing of these “wallpapers” could eventually move to high-speed industrial printing.
Frequently Asked Questions
Can this replace solar panels?
No. The electricity produced cannot compete with solar panels, but it is designed to generate an extra bit of power that would normally go to waste, which can then be used to power sensors, wireless devices and other electronics that don’t need a lot of power.
Does it work in dry air?
The 1,596-unit panel produced roughly 3.5 volts even at about 38 percent humidity.
What happens if the center of the generator is blocked?
Output declines. Testing showed that covering the wax center allows some power at first, but output declined as the paper filled with water.
What do you think about the future of energy-harvesting interiors? Could you see yourself using “power-generating wallpaper” in your home or office? Let us know in the comments below or subscribe to our newsletter for more updates on sustainable technology.
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