Wednesday, August 27, 2025

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• Waste nut, want nut: researchers generate power from walnut shells

• Welcoming new Warriors to Orientation

• The Waterloo Magazine turns its final page

Waste nut, want nut: researchers generate power from walnut shells

A news release from the Media Relations team.

Researchers at the University of Waterloo have developed an inexpensive device that generates enough electricity to power a calculator using only waste walnut shells and drops of water.

The coin-sized device – known as a water-induced electric generator (WEG) – produces electrical energy as water evaporates from a complex network of pores that make up the shell structure.

“It all happens with nothing more than a single droplet of water and the shell’s natural architecture, no crushing, soaking or complex processing needed,” said Nazmul Hossain, a Waterloo PhD student in mechanical and mechatronics engineering. “It’s a simple, yet powerful example of turning waste into clean energy using nature’s own power.”

At the heart of the technology, a form of hydrovoltaic energy harvesting, is how evaporating water flows through the porous structure of nut shells. As the water moves, it transports electrically charged ions, which interact with the surface of the shells to create a charge imbalance that generates electricity.

Hossain was inspired to develop the device after he ate a hazelnut and examined its shell under an electron microscope. The complex structure he observed, part of the nut’s internal system to transport water and nutrients for growth, struck him as ideal for energy harvesting.

Testing with four kinds of nuts showed walnuts have the greatest potential to produce power. Researchers then optimized walnut shells for that purpose by cleaning, treating, polishing and cutting them into precise shapes.

By connecting four WEG units – each one comprised of shells, water droplets, electrodes, wires and a 3D-printed case – the Waterloo team was able to generate enough electricity to power an LCD calculator.

“This technology could be a game-changer for powering small electronic devices, especially in remote or off-grid areas,” Hossain said. “Imagine environmental sensors monitoring forests, IoT and wearable health devices, disaster-relief equipment – all running on tiny water droplets from the air.”

Researchers are now working to develop wearable WEGs capable of harvesting energy from sweat or rain, and on practical applications such as powering sensors to detect water leaks. They have also experimented with the use of wood instead of nut shells.

Hossain was supervised by Dr. Norman Zhou, a professor of mechanical and mechatronics engineering, and Dr. Aiping Yu, a professor of chemical engineering.

A paper on the research, Hydrovoltaic Energy Harvesting From Nut Shells, was recently published in Energy & Environmental Materials.

Welcoming new Warriors to Orientation

A message from the Student Success Office (SSO).

Tomorrow, we begin welcoming more than 11,000 new undergrad and grad students to Waterloo.

Here are the highlights:

• August 28 and 29: International students get settled and learn about life in Canada at International Orientation;
• August 28 to September 6: Students move-in to on-campus residences (August 28 to 31) before all first-year students kick off Waterloo Orientation (August 31 to September 6);
• August 29, 30 or 31: Warrior Family Orientation runs in Village 1 (V1) Great Hall;
• September 2: Graduate Orientation welcomes grad students in Physical Activity Complex (PAC), Student Life Centre (SLC), Health Expansion Building (EXP), and Graduate House (GH);
• September 3: Drop-in events continue for new undergraduate students as classes begin;
• September 6: Orientation wraps up with an action-packed Black and Gold Day.

More than 1,000 upper-year students are involved in planning and delivering Orientation experiences across campus.

Find out where undergraduate students are by using the open Orientation schedule in Portal.

The Waterloo Magazine turns its final page

This is the latest article from the 2025 issue of Waterloo Magazine.

The story of the Waterloo Magazine is one of history, community, innovation and evolution. To make way for exciting new changes, 2025 Waterloo Magazine is the last planned issue of the publication.

For the past 60 years, the Waterloo Magazine has shone a light on remarkable Waterloo graduates who are making positive local, national and global impact. As we say goodbye, we revisit key moments that have shaped this publication into a cherished beacon for the University of Waterloo alumni community.

Read about the history and impact of the Waterloo Magazine through the decades.