Hybrid device harvests both mechanical and magnetic energy

July 16, 2018 by Lisa Zyga, Phys.org feature
The hybrid energy harvester consists of a cantilever beam made of a magnetostrictive/piezoelectric material that harvests both magnetic and mechanical energy. Credit: Xu et al. ©2018 American Institute of Physics

A new hybrid energy-harvesting device may one day replace the need for batteries in certain low-power electronics devices. The new device collects ambient wasted energy from both mechanical vibrations and magnetic fields to generate sustainable electricity, which could potentially provide enough power to run wireless sensors, cardio pacemakers, and other applications.

The researchers, led by Fulei Chu at Tsinghua University in Beijing, have published a paper on the new hybrid device in a recent issue of Applied Physics Letters.

Over the past several years, energy harvesting has become an increasingly attractive option for replacing the batteries that are used in low-power devices. Whereas batteries have a limited lifetime and must be replaced or recharged on a regular basis, energy-harvesting devices can ideally operate autonomously for much longer periods of time.

One of the greatest challenges facing energy harvesters is generating enough power for practical applications. One way to increase the output power is to harvest more than one type of energy. For example, although there are a variety of devices that harvest either mechanical energy or magnetic energy, very few devices can harvest both, despite the fact that ambient mechanical and magnetic energy often appear together in industrial settings, such as near rotating electrical machines.

In the new study, the researchers showed that mechanical and are "interactive," so that, when combined, they increase the optimal output power above the level that is possible using each type of energy alone. They demonstrated the improvements both theoretically and experimentally using a cantilever beam made of a magnetostrictive/pieozoelectric laminate material, which moves in response to both magnetic fields and vibrations.

"We have proposed the idea of taking advantage of two different energy harvester approaches and showing their interactions," Chu told Phys.org. "As we know, energy harvesters have been investigated for decades and many methods are involved. However, each approach has its shortcomings. It is difficult and interesting to break through the single energy harvester limitations. Moreover, revealing the interactive relationship is important for the work as a whole."

Among their results, the researchers found that the power output depends on whether the mechanical and magnetic excitations have the same or different frequencies. If the frequencies are the same, then their phase difference (how much one wave is shifted with respect to the other) directly affects the . On the other hand, if the frequencies are different, then the phase difference has little effect on the output voltage, and in fact the hybrid output voltage is no longer a simple sine wave.

With these insights, the researchers demonstrated improvements in the energy capacity, reliability, and optimal output power of the hybrid energy-harvesting device. Overall, they believe that the performance suggests that the hybrid approach offers a promising alternative for powering low- electronics in the future.

"We plan to conduct deeper research in the energy harvester field in the future," Chu said. "Wind energy, wave energy, and more smart material applications in systems will be the focus of our research besides the further investigations of this paper."

Explore further: Hybrid nanogenerator harvests hard-to-reach ocean energy

More information: Xueping Xu et al. "Hybrid energy harvesting from mechanical vibrations and magnetic field." Applied Physics Letters. DOI: 10.1063/1.5038412

Related Stories

Hybrid nanogenerator harvests hard-to-reach ocean energy

June 21, 2016

(Phys.org)—Energy from the ocean, or "blue energy," is arguably the most underexploited power source, according to researchers in a new study. Although the oceans contain enough energy to meet all of the world's energy ...

Slip-and-slide power generators

May 24, 2012

Researchers from Vestfold University College in Norway have created a simple, efficient energy harvesting device that uses the motion of a single droplet to generate electrical power.

Energy harvester collects energy from sunlight and raindrops

March 8, 2018

By attaching a transparent nanogenerator to a silicon solar cell, researchers have designed a device that harvests solar energy in sunny conditions and the mechanical energy of falling raindrops in rainy conditions. The dual ...

How ambient energy could power the Internet of things

August 9, 2017

In the modern world, we are increasingly surrounded by digital sensors, cameras and communications devices sending data cloud-based analysis services. Those devices need power, and designers are finding new ways to draw it ...

Recommended for you

Researchers study interactions in molecules using AI

October 19, 2018

Researchers from the University of Luxembourg, Technische Universität Berlin, and the Fritz Haber Institute of the Max Planck Society have combined machine learning and quantum mechanics to predict the dynamics and atomic ...

Pushing the extra cold frontiers of superconducting science

October 18, 2018

Measuring the properties of superconducting materials in magnetic fields at close to absolute zero temperatures is difficult, but necessary to understand their quantum properties. How cold? Lower than 0.05 Kelvin (-272°C).

The big problem of small data: A new approach

October 18, 2018

Big Data is all the rage today, but Small Data matters too! Drawing reliable conclusions from small datasets, like those from clinical trials for rare diseases or in studies of endangered species, remains one of the trickiest ...

2 comments

Adjust slider to filter visible comments by rank

Display comments: newest first

Thorium Boy
1 / 5 (1) Jul 17, 2018
It'll never happen. Someone should go back, look at all the stories of wonderful, impending inventions announced here and in other venues and SEE how many have come to fruition. I'd wager next to none.
rrwillsj
1 / 5 (1) Jul 17, 2018
Oh yes TB. You are so right! Nuclear Energy has been such a total fail. So lets give up on all this existentialist angst research.

Good news is TB, you can always fall back on your family lineage as charcoal burners. Yes, such an exciting profession for one with your limited intellect.

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.