Clever kid builds phone charger powered by pet hamster

Renewable energy is the cornerstone of any sustainable society, but why limit your options to wind or solar installations? In the United States alone, over one million homes host a tiny, furry alternative power source without even realizing it. As a young YouTuber known as Flamethrower recently demonstrated, it’s time for hamsters to start pulling their weight around the house. Or, at the least, it’s time for them to start turning hamster wheels into miniature, makeshift turbines.

The idea came to Flamethrower after his brother received one of the tiny pets for his birthday. Although adorable, naturally nocturnal hamsters are often up at all hours of the night running on their little exercise accessories. While laying awake to the sound of a spinning, squeaky wheel, the amateur engineer realized how to make the best of an unexpectedly annoying situation.

“So what did I do? Exploit it for energy production, of course!” he declared in his recent video entry.

Can A HAMSTER Charge My Phone?

Turbines help generate most of the world’s energy, and their underlying principles are simple enough. Electricity funneled through wires to a motor will make it spin, but the reverse is also true—spin a motor, and electricity will generate through its terminals into battery storage. The fundamentals are basically the same whether a turbine spins thanks to steam, wind, or nuclear power. Or hamsters.

However, a hamster-powered turbine is not the easiest project to design. As the YouTuber explained, a 5 volt (V) DC motor hypothetically needs to spin at over 10,000 RPM to simply reach a smartphone’s standard 15 watt charging speed. Even if such a superpowered hamster existed, its speed would likely cause the motor to melt before it provided any juice to a battery—and therein lay another issue. 

Batteries don’t only store energy—they are designed to provide electricity at a steady current when needed. However, a standard battery also must receive a higher voltage than it stores in order to amass any reserves. 

Part of the solution came from a device known as an energy harvester module, which takes small voltages and amplifies them to an acceptable level for a battery. But the problem is that the amount of required voltage increases in direct proportion to the energy that’s being stored, meaning yet another unfeasible hurdle. The hobbyist ultimately relied on a system called maximum power point tracking (MPPT) to calculate the optimal input and output proportions for the energy harvester and a few other components. 

All that potential energy is only as good as the battery that stores it, however. For this project, the YouTuber relied on lithium-ion cells salvaged from a broken electric scooter. Flamethrower hooked up his rig to the hamster wheel’s axis, then gave his brother’s pet the night to get its steps in. The next day, he attached his phone via a USB cable charging port to test the whole thing for the first time.

The initial setup worked flawlessly, although it charged at a snail’s pace. Naturally, he booted up his thermal camera nearby (who doesn’t own one?) to investigate any pain points in the system. It turns out the issue did have anything to do with the hamster wheel charger itself, but his outdated USB cable. After swapping that out with a newer replacement, phone charging sped up dramatically.

“And with that, my hamster’s life finally has a purpose,” the inventor declared.

As absurd as it appears, it’s hard to argue with such an ingenious source of free electricity. Hypothetically, the same idea could be adapted to basically anything in a house that spins mechanically, like a stationary bike. Then again, the whole point is to have the hamster do the work, not you. In any case, the YouTuber seems to be on to something here. The way Flamethrower tells it, the rodent may be more reliable than solar or wind energy.

“It’s supposed to be nocturnal but I’m starting to think it never sleeps,” he said.

In The Workshop, Popular Science highlights the ingenious, delightful, and often surprising projects people build in their spare time. If you or someone you know is working on a hobbyist project that fits the bill, we’d love to hear about it—fill out this form to tell us more.

 

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