No Battery Required: How Energy Harvesting Charges an IoT Future

August 27, 2025

Summary: Energy harvesting refers to the practice of capturing ambient energy from the environment. It includes forms of energy you’ve probably heard of, like solar and wind energy, and some that are more obscure, like vibration and motion energy. It is the subject of intense research because it allows Internet of Things (IoT) devices to be installed without a wired power supply and without the need for regular battery changes. One of the biggest issues on the research agenda is that ambient sources often fluctuate.

The number of IoT devices is projected to more than double from 19.8 billion in 2025 to more than 40.6 billion by 2034. Most of these devices are either plugged in or powered by batteries.

That has two big drawbacks: Energy production usually has environmental impacts. And batteries need to be changed regularly. That’s not so easy when there are lots of devices, or when they are used in remote locations.

This is where energy harvesting can provide a solution.

“Energy harvesting is the process of capturing small amounts of energy from the environment, such as sunlight, heat, motion or radio waves, and converting it into usable electricity,” said IEEE Member Shreenithi Lakshmi Narasimha.

According to IEEE Senior Member Alandey Severo da Silva, the primary objective of energy harvesting is “to enable devices to operate autonomously, thereby reducing or completely eliminating the reliance on traditional batteries.”

What Does Energy Harvesting Look Like?

There are a number of ways that devices can harvest energy in place of batteries.

For example, “solar-powered calculators convert sunlight into electrical energy, while self-winding watches harness the mechanical energy generated by the wearer’s arm movement,” continued Silva.

Examples can also include sensors that derive power from the vibrations of structures, such as bridges, which can capture vibration energy. Wearable devices that use body heat, or thermal energy, to generate electricity. Future devices are capable of capturing energy from ambient Wi-Fi signals because these are electromagnetic waves.

Solar-powered garden lights, wristwatches that run on body heat or even phone chargers powered by walking are everyday examples of how ambient energy can be captured and used without relying on traditional batteries or power outlets.

The Benefits of Energy Harvesting

In 2025, 78 million batteries powering IoT devices are expected to be dumped every day globally. “With billions of IoT devices coming online, the environmental cost of battery production and disposal is unsustainable,” said Lakshmi. “Energy-harvesting technologies will be key to achieving net-zero electronics.”

Not only does energy harvesting provide a sustainable solution to battery technologies, it opens the door to streamlining network architectures in 6G and next-gen wireless systems.

“The use of ambient energy harvesting can help create self-powered devices, which will bring greater autonomy to networks,” IEEE Senior Member Maria Crueza Borges de Araújo said. “In remote environments where there isn’t adequate infrastructure for the use of current wireless systems, new energy-harvested devices can increase the scalability of 6G or next-generation networks and sensors can be placed in remote locations without the need for constant recharging or battery replacement.”

Energy harvesting also provides greater design flexibility as these devices do not need to accommodate bulky batteries or charging ports. This allows for new product designs and applications that were previously impossible.

“Designs will shift toward modular, passive and energy-conscious architectures that reduce battery dependence. Wearables may use motion and body heat harvesting, enabling thinner form factors and extended lifespans without frequent charging,” IEEE Senior Member Dheerendra Panwar said.

Challenges with Energy Harvesting

Despite its ability to offer more sustainable solutions to IoT development and usage, challenges remain when it comes to how quickly and widely energy harvesting is being adopted.

According to Lakshmi, “the biggest challenge is consistency. Ambient energy sources fluctuate. Sunlight isn’t always available, radio frequency signals may be weak and motion isn’t guaranteed.”

In order to address the challenge with inconsistent energy sources, it is critical to couple energy harvesting with ultra-low-power design, edge intelligence and smart energy storage, she added.

Another issue is the increased initial costs that come with technologies using energy harvesting. Economic barriers may arise due to the high costs of materials and manufacturing processes associated with energy harvesting devices.

Despite these initial costs, however, the long-term cost benefits ultimately reduce the cost over the product lifetime. Energy harvesting minimizes the battery replacement costs, maintenance and increases the reliability of the overall device.

What’s Next for Energy Harvesting

In order to achieve widespread use of energy harvesting, advancements in both technology and government support are needed.

Energy storage must be enhanced by designing more efficient and compact systems that can manage the variable supply of harvested energy.

“Improving energy conversion efficiency is also critical,” Silva said. “This requires the development of materials that can more effectively transform ambient energy into electricity with minimal waste. Making these materials more affordable and durable is also necessary to reduce manufacturing costs and increase device lifespan, making them accessible for broader use.”

Lakshmi identifies more make-or-break factors:

“Scalable, low-cost energy harvesting modules that can be integrated into existing manufacturing pipelines, ideally with open standards for interoperability and incentives for circular electronics, stricter e-waste regulations and mandates for low-power wireless standards are needed to accelerate adoption,” she said.

Energy harvesting can offer sustainable alternatives to the growing use of IoT devices worldwide. As battery usage increases, investing in solutions that prioritize energy harvesting capabilities can help minimize the increasing energy demand and consumption.

To learn more, visit: How to Collect the Positive Energy That’s Around Us? Energy Harvesting Makes an Entrance