There is growing number of new companies that aim to extract small amounts of energy from environmental sources. This generation of energy harvesting startups is largely focused on delivering power for the plethora of IoT sensors around today.
The vision of wireless energy is not a new concept — it’s just orders of magnitude less ambitious about the amounts of power involved. The idea of transmitting electrical power through the air originated with the famed and troubled inventor Nikola Tesla way back in the late 1890s.
Tesla was interested in transmitting electric power over distance through the air. The inventor’s early experiments in Colorado Springs in 1899 involved a Magnifying Transmitter, a 52-foot diameter electrical coil that sent 130-foot lightning arcs into the air.
At the turn of the 20th Century, the Serbian engineer built Wardenclyffe Tower in Shoreham, New York. Initially constructed to transmit telegraph messages across the Atlantic, Tesla planned to increase the scope of Wardenclyffe to develop the first-ever wireless power transmission system. When he could not get the necessary funding for the changes to the tower from gilded age uber -banker and project backer, J.P. Morgan, Tesla abandoned Wardenclyffe in 1906.
Tesla had ambitiously planned to develop a World Power System that was to broadcast free electricity around the world. Obviously, this never actually happened!
The Long Island tower was supposed to be the initial stage in the system but the Wardenclyffe scheme fell at the first hurdle. The structure was demolished for scrap in 1917.
Wireless transmission of energy remained a sci-fi fantasy for the rest of the 1900s. Roughly 115 years after Tesla first mooted the concept, wireless energy harvesting startups have come into focus anew, as mechanisms for sending tiny amounts of power over very short distances to specialized industrial tasks and consumer devices.
Compared to Tesla’s original failed dream, most of the new firms are offering wireless ambient energy harvesting ideas that are puny. The bulk of today’s energy harvesting companies — apart from Emrod in New Zealand — are focused on scavenging small amounts of power from radio waves, Wi-Fi, ultrasound, or other ambient sources.
Everactive Inc is currently the top dog in the energy harvesting parade, thanks to recently closing a Series C venture funding round of over $50 million. This round was bumped up due to $16 million in strategic funding from 3M and Ericsson, which was announced on July 29, 2021. The company has scored more than $114 million in funding since it was founded in June 2012.
The startup, which was originally called PsiKick, has developed a batteryless sensor (called EverSensor in the company’s technology blurb) that harvests energy from indoor and outdoor sunlight, thermal gradients, RF, vibration, and more. Everactive’s latest production chip technology delivers wireless non-line-of-sight communication up to 250 meters (820 feet), a distance equivalent to nearly three football fields.
Everactive is going after traditional industrial IoT (IIoT) sectors with its products. It boasts of how a sensor can be installed on a steam trap (STM) in 5 minutes, and a gateway can support 1000 STM sensors in operation. The company’s aim is to continue to shrink its batteryless sensors with each generation.
Belgium-based e-peas S.A. enables power harvesting from multiple light sources (the sun, bulbs, and natural indoor lighting), numerous heat and vibration elements, as well as various RF bands (868MHz, 915 MHz, 2.4 GHz, etc). Like Everactive, e-peas’ technology is based on its silicon chip, however, the young firm offers a number of different microchips to gather the various types of energy it can scavenge from the air, including specific silicon designed for extracting power from light, vibration, and radio waves.
The semiconductor company has scored $13.8 million in funding so far. The chip firm has partnered with companies such as SODAQ, which has developed a solar-powered IoT asset tracker that uses e-peas’ AEM10941 chip.
Dutch startup Nowi Energy has earned 10.5 million euros in venture funding so far. The company is funded by Netherlands-based investment firm Disruptive Technology Ventures.
Nowi has developed the NH2 energy harvesting power management IC. It has worked with Huawei’s chip arm HiSilicon to combine the H2 with the Chinese firm’s NB-IoT solution. (No surprise that a Chinese company would be looking to create a power harvesting system that supports NB-IoT!)
Nowi is working with companies like Murata Manufacturing and Nordic Semiconductor to combine its power management chip with various Low Power Wide Area (LPWA) specifications including LoRaWAN, SigFox, as well as LTE-M and NB-IoT.
The company is selling its NH2 product as one of the smallest power harvesting ICs available, suitable for use in industrial IoT sensors and electronic shelf labels (ESL), as well as consumer products, such as TV remote controls. The Nowi chip derives energy from either light or vibration, but it can’t derive power from both sources simultaneously.
There are many other energy harvesting startups, such as 8Power, Quester, and Wiliot, that are securing funding despite the blight of the Coronavirus that is still ravaging many industrial sectors worldwide. We could be seeing a mini-boomlet in venture cash for energy harvesting startups is underway.
The reason is obvious. Removing batteries from the industrial equation cuts costs and reduces the hours that people spend replacing them. Using batteryless equipment in industrial and consumer settings could also greatly reduce the number of batteries that are thrown into landfills around the globe. It is estimated that 3 billion batteries a year are discarded in the U.S. alone!
For instance, Everactive argues that if you were to deploy 10,000 battery-powered industrial IoT sensors across your facility to transmit real-time data about the health of your machinery, over time your team would be replacing around 2,000 batteries a year. Many of these sensors would be located in difficult-to-reach areas, further increasing the time and expense needed to replace the chemical cells.
We’re in the earliest stages of energy harvesting for IoT. Simply implementing solar-powered steam trap sensors won’t save vast amounts of energy or stop batteries from being widely used across the world. You’ll still see the grim effects of climate change, from rampaging wildfires to drastic shifts in rainfall patterns, eating away at a liveable environment for humans on earth. Still, we have to start somewhere, and energy harvesting could eventually turn out to be one of the elements that lead the way to a greener future.
>> This article was originally published on our sister site, EE Times.
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