If there’s one thing we know about batteries, it’s that they eventually run out. The proliferation of electronic devices like phones, computers and television sets – just to name a few – has led to increased demand for batteries, many of which are heavily dependent on resources in limited supply.
Engineers are increasingly tasked with finding sustainable and efficient alternatives to this traditional power source. One such solution lies in energy harvesting: a technology that captures ambient energy from the environment and provides a cleaner and more reliable way to meet our increasing energy demands. So, why is energy harvesting so important? Let’s dive in.
Seeking A Battery-Free Future
Batteries often contain scarce and toxic materials such as:
- lithium
- cobalt
- nickel
Their production involves mining in remote locations and is often done under unethical circumstances. Not only does this mining deplete our natural resources, it also generates pollution that damages our ecosystems, often leaking into our soil and water sources.
The challenge of energy storage is especially evident in wearable electronics like pacemakers, which require frequent recharging, leading to inefficiency, inconvenience and even safety concerns due to repeated surgery to reinsert new batteries.
Our dependency on batteries as a power source has also kept us from developing technologies that use a continuous power supply, making clean energy alternatives like energy harvesting an essential and rich area of exploration for future engineers.
A Clean Energy Alternative
Energy harvesting captures and converts ambient energy from sources like light, heat and vibrations into electrical power, harnessing and storing otherwise wasted energy. Solar panels, for example, are powered through energy harvesting: Heat is captured through photovoltaic cells which then generate a flow, creating electricity.
This method of energy production must be tailored to the specific device being used. Piezoelectric energy harvesting, for example, uses materials such as quartz or ceramics that generate electricity when mechanically stressed. This method of “vibration” (or kinesthetic) harvesting is already in use in places like Israel’s highways, where piezoelectric materials have been integrated beneath the asphalt. The pressure from vehicles driving over the road generates electricity that powers streetlights, traffic signals and even feeds back into the grid. This kind of energy can also be captured in everyday items, like shoes and clothing via triboelectric energy.
Electrodynamic vibration generators, on the other hand, function via a moving magnet within a coil, where vibration causes a current. This technology is most effective in places with consistent vibrational energy, such as industrial machinery or bridges. General Electric uses thermoelectric harvesting devices to power their machinery.
We are surrounded by natural energy that remains largely untapped. For nearly any type of energy – whether solar, wind, water or heat – a method of harvesting and storing excess energy can be developed.
Energy Harvesting Applications
Energy harvesting has been applied for decades in solar panels, wind turbines and hydroelectric dams. It’s also becoming prevalent in wearable technology, smart homes and industrial sensors. Wearable devices like fitness trackers and smartwatches utilize harvested energy from body movements or temperature differences, extending battery life or even eliminating the need for batteries altogether. In industry, energy harvesting powers wireless sensor networks for continuous machinery monitoring, enhancing predictive maintenance and reducing downtime.
With such recent strides revolutionizing the energy landscape, what does the future of this technology hold?
Future Trends
Energy harvesting has nearly endless applications. As the need to transition to clean energy and efficiently power emerging technologies like the Internet of Things (IoT) becomes more critical, energy harvesting will become more essential as an alternative source.
Some of the types of vibrational energy that could provide power for our daily lives include:
- body motion energy
example: wearable fitness trackers - thermal energy
example: smartwatches - vehicle pressure energy
example: smart roads - industrial vibrations
example: wireless sensor networks - wind energy
example: the powering of remote weather stations - body heat
example: implantable health monitors - foot traffic energy
example: the powering of building infrastructure
Pioneer Future Energy Use with a Mechanical Engineering Degree
The future of energy harvesting is bright, with applications ranging from body motion energy in wearable devices to industrial vibrations powering sensor networks. As the demand for clean energy grows, so will the need for skilled engineers to innovate and develop these technologies.
If you’re passionate about pioneering future energy solutions like energy harvesting, consider the 100% online mechanical engineering degree from The University of Texas at Austin. This program, led by renowned faculty, provides a comprehensive foundation in energy systems, materials science and innovative technologies. Students will learn to tackle global energy storage challenges and develop sustainable solutions for future industries.
Ready to join the engineers of tomorrow? Apply here!
Sources:
https://www.analog.com/en/resources/glossary/energy-harvesting.html
https://www.iis.fraunhofer.de/content/dam/iis/de/doc/lv/los/energie/Mechanical_Energy_Harvesting.pdf
https://www.mdpi.com/2624-6511/4/2/25
https://facilitymanagement.com/smart-building-energy-harvesting
