close
close

The “drinking bird” is back and can power your gadgets with clean energy

The top-hatted “drinking bird,” once a fixture in science classrooms to demonstrate the basics of thermodynamics, is now making a surprising comeback – as the inspiration for a new clean energy generator that could one day power your watch and phone.

Scientists in Hong Kong and China have used the famous toy, also known as the “Dippy Bird,” to develop an engine capable of harnessing the power of water evaporation to generate electricity, according to research published Thursday in the journal Device.

The new method involves converting the energy produced by the bird’s characteristic back and forth movement into electricity.

The physics behind it is relatively simple: the toy consists of two glass bulbs, representing the head and body of a bird, connected by a long glass tube. The structure contains methylene chloride, a highly volatile liquid.

After the bird’s beak is immersed in a bowl of water, it returns to its natural vertical position and the water begins to evaporate and cool the head. This causes the volatile liquid in the lower bulb to rise up the tube due to the pressure difference, causing the bird’s center of gravity to begin to shift, tilting its beak back into the water.

It is a process that has entertained generations of children and adults alike. But it is also a process that occurs naturally on Earth and can be used to produce clean energy.

In the natural world, evaporation occurs when sunlight heats the Earth’s surface, breaking the bonds that hold water molecules together. This causes liquid water from oceans, lakes and other surface water to turn into steam. It is the driving force of the natural water cycle on Earth.

According to the study, this process uses half of the solar energy absorbed by the Earth’s surface and results in “the most significant energy transfer on Earth.”

The authors say that if scientists can capture this energy and convert it into electricity, it could represent a “significant renewable energy opportunity.”

Lead author Hao Wu, a professor at South China University of Technology, says the bird drinking method offers a “unique” way of generating electricity using water, “a readily available fuel source.”

“I am still surprised and excited to witness the actual results,” Wu said.

During her graduate studies, Wu realized that the drinking bird model could be more than just “a tool to demonstrate physics concepts.”

“I started wondering if we could first convert evaporative energy into mechanical energy and then translate it into electrical energy,” Wu said. “Then the idea of ​​using a drinking bird toy came to my mind.”

Wu and her colleagues added two nanogenerator modules — tiny devices that convert mechanical energy into electrical energy — on either side of the bird’s “engine,” which was made from a commercial toy.

They then tested the prototype’s ability to power a range of electronic devices under ambient conditions, including liquid crystal displays (LCDs), temperature sensors and calculators. The idea is that one day the generator could be used in increasingly common everyday devices.

Previous attempts to convert evaporative energy into electrical energy have been characterized by low conversion efficiency. However, using the drinking bird method, the researchers were able to generate an output voltage of 100 volts using just 100 milliliters of water, enough to power small electronic devices.

The authors claim that their drinking bird generator can produce significantly more power than previous experiments that used other methods.

The team’s next goal is to design their own drinking bird that can use the power of evaporation more effectively.

If they can pull this off, the retro drinking bird may be here to stay.

For more CNN news and newsletters, create an account on CNN.com