Wallpaper That Makes Electricity From Indoor Humidity

Your walls could soon pull double duty as power sources. Engineers at Binghamton University in New York have built a paper-based wallpaper covered with 1,596 tiny power-generating tiles that harvests electricity from indoor humidity, and a full panel of them ran a wireless keyboard with no batteries at all, according to the university's October 1, 2026 announcement.

The prototype needs no sunlight, wind, or fuel. Each tile simply drinks water vapor from room air and turns the flow of moisture into a small, steady electric current. The technology is aimed at generating electricity from indoor humidity for low-energy electronics rather than replacing mains power, and the team detailed the work in the journal Advanced Energy Materials.

The trick to making electricity from indoor humidity is plumbing, not brute force. Each tile is a small paper square with jobs split across its surface: glycerol-soaked edges pull water vapor from the air, a raised wax-patterned center controls how fast moisture escapes, and a polymer layer in between steers water in one direction. As water moves through the treated paper, it frees charged particles called ions, which drift unevenly and build up a voltage, essentially a tiny battery made of damp paper. All the wiring hides behind the wallpaper, carried through laser-drilled holes filled with silver paint, so the finished wall looks like any other wall.

Harvesting electricity from indoor humidity at scale

The lab measurements put hard numbers on electricity from indoor humidity. At 80 percent relative humidity, damper than most rooms, a single tile produced about 0.34 volts and a peak power density of 2.2 microwatts per square centimeter, as reported by Nanowerk. Ten tiles wired together delivered roughly three volts, and with the intake and exhaust zones both open, output held steady for about 270 minutes. In a room-level test at about 38 percent humidity, each tile made roughly 0.2 volts, and the full panel, paired with a small capacitor to smooth demand spikes, powered a wireless keyboard well enough for real-time typing, as reported by Tech Xplore.

Why the indoors beats the outdoors

The team calls the devices moist-electric generators, and their core insight is about keeping water moving. Earlier designs absorbed water and released it through the same surface, so damp and dry zones quickly evened out and the current died within minutes. This wallpaper separates intake from exhaust: moisture enters at the tile's edges and leaves as vapor through the wax-patterned center, so the one-way flow, and the voltage, keeps going. The researchers describe it as the first wallpaper built on this principle.

Earlier moisture harvesters mostly chased outdoor air in the long-running quest for electricity from indoor humidity, using materials such as graphene oxide, gels, bacterial spores, and protein strands grown by bacteria. But outdoor conditions swing wildly. The work was led by professor Seokheun "Sean" Choi of the Thomas J. Watson College of Engineering and Applied Science, with doctoral student Guangya "Roger" Yuan and recent graduate Yang "Lexi" Gao, according to the university's release, and Choi argues the indoors is the steadier bet. He said earlier devices targeted "outdoor humidity," where conditions "are not stable because of extreme sunlight or weather." Inside, humidity sits in a steadier band, the team cites 30 to 60 percent, and everyday life keeps topping it up: breathing, cooking, and showering all add moisture to room air. Choi's lab has form in this area: in 2024 it built a paper-based wearable that pulled power from air moisture using bacterial spores.

What this could actually power

That steadiness is the bet behind harvesting electricity from indoor humidity instead of chasing storms outside. The target uses are small: environmental sensors, wireless communication modules, smart-building interfaces, and other Internet of Things devices that sip microwatts to milliwatts. A wall offers an enormous surface compared with a conventional component, so instead of demanding big output from one tile, engineers can spread thousands of them across a room. Smart-home hardware keeps multiplying, Apple's latest smart-home hub launch is one sign of the appetite, and every connected gadget needs power, ideally without a battery to replace or an outlet nearby.

The catches

For now, electricity from indoor humidity is a trickle, and several problems are unsolved. The output per tile is a few microwatts per square centimeter at best, enough for sensors, not for anything with a screen or a motor. Durability is unproven: paper swells and shrinks with every humidity swing, which could eventually crack the silver-paint wiring, and the glycerol that gathers moisture may slowly creep across the tile over days or weeks and blur the zones that make the current flow. The prototypes survived tens of such cycles in testing, while a real wall would face hundreds or thousands. The wallpaper also exists only on laboratory paper so far, and the team has yet to tune the balance between gathering water and collecting current.

There is a bonus function, though: the same tiles act as a passive dehumidifier. In a sealed test chamber, 28 squares pulled air from about 75 percent humidity, damp enough to encourage mold, down to about 50 percent in four minutes. If the yields climb, electricity from indoor humidity could turn the largest surface in your home into a quiet power source and a moisture manager at once. For more lab breakthroughs, see our science coverage.