Connected devices—if you look around, they’re everywhere. Every year, more and more devices become intelligent through connection to the Internet, from smart thermostats in homes to multitudes of sensors in large industrial environments. As we march towards a brave new world, such as smart cities, autonomous vehicles, telehealth, building automation, agricultural IoT and more, this trend is only accelerating. Norton predicts the number of connected devices will balloon from 4.7 billion, only four years ago in 2016, to roughly 11.6 billion devices in 2021, to over 21 billion by 2025. Unfortunately, the amount of electricity these devices will consume may offset the benefits. One of the novel concepts that aim to curb this problem is energy harvesting. Let’s look at what it is, why it’s promising and what options are out there for those looking to employ it.
Tackling an impending energy crisis
On the datacenter and cloud side of the IoT chain, power-hungry servers are perpetually running. Conversely, the many endpoints have much lower energy requirements and generally require much less uptime. As of 2017, according to a presentation at the World Material Forum 2018, datacenters already made up 3% of the worldwide energy consumption. Extrapolated using Moore’s Law, this could mean that by the year 2037, the energy needs of computers will exceed that of our current global production of electricity.
This high demand would be a severe problem, especially with our continued energy reliance on fossil fuels and scientists’ increasingly dire warnings of climate change. Luckily for us, there are other, sneakier ways to generate energy than plugging into the grid or continually replacing batteries (imagine having to do that in a factory that employs 1,000+ nodes). Enter energy harvesting: the practice of scavenging and harnessing trace amounts of energy from the surrounding environment. While historically such small amounts of energy would be virtually worthless, we’ve seen the emergence of ultra-low-power semiconductors in recent years. Some may wonder why—if these solutions require so little power—we should worry about our global energy footprint? But one must consider that we’re talking about billions, eventually trillions, of these low-power devices—they add up in a big way.
Often employed en masse as sensor nodes in IoT applications, these solutions are ripe to benefit from energy harvesting. Perhaps the most well-known energy harvesting technique is the employment of solar panels. Still, there is a myriad of creative sources you can harvest energy from, including vibrations, heat and light. That brings us to ON Semiconductor, a company doing some exciting things in the energy harvesting realm.
ON Semi has been on my radar for several years for its ultra-low-power semiconductors, switches, sensors, automotive electrification systems and more. It’s not a new company—it originally spun off of Motorola back in 1999—but the company’s increasingly strong position in the automotive market has made it one to watch these days. ON Semi’s portfolio is impressive and diverse. On top of that, I appreciate the emphasis it puts on its low-power solutions’ ability to reduce carbon emissions—helping the environment and business at the same time. I also appreciate the efforts the company has made during the Covid-19 pandemic. Many of its technologies appear in medical devices, including ventilators. As such, it has continued to operate safely as an essential business throughout the crisis. The company has also donated nearly 10,000 medical-grade masks and other personal protective equipment to first responders worldwide.
That is all admirable, but today we’re here to talk about energy harvesting. I wanted to focus on ON Semi’s RSL10 Bluetooth Low Energy switch, a collaboration between the company and ZF. Combining ON Semi’s RSL10 Bluetooth 5-certified radio with a ZF energy harvesting switch, the reference design provides a blueprint for harnessing the dynamic energy derived from flipping the switch off and on. Together, ON Semi says they comprise a blueprint for battery-less IoT applications, which self-powers on a tiny 300 joules of energy. The RSL10 radio’s Bluetooth Low Energy frame protocol can be as quick as 10ms, requiring a total energy budget of fewer than 100 joules. To be clear, that’s 300 joules of harvested energy and a requisite transmit budget of only 100 joules. Additionally, ZF’s switches have an impressive lifespan, continuing to function for up to 1,000,000 switching cycles thanks to its small size and high efficiency.
One can see an example of this offering’s potential in ON Semi’s Modular Kit for Industrial LED Applications. Through the kit’s RSL10 Sense and Control app, this connected lighting platform supports on/off, dimming and telemetry functionalities for advanced, battery-less lighting control in industrial settings.
A big plus of these energy-harvesting, low power solutions is that they are small due to their lack of a battery carriage and much more convenient for installation since they require no cords to operate. Imagine the ability to brighten up a dark corner of your house without having to cut a new hole into the sheetrock and deal with the headache of wiring a new light switch. Wireless switches are already gaining in popularity in the consumer realm, albeit battery-powered ones. Battery-less lighting takes this idea further. These solutions hold much promise for industrial IoT applications—they can be installed in small, confined, perhaps hard-to-access spaces, and don’t require workers to lay massive amounts of cable or go through the hassle of changing batteries over and over again.
If we gaze even further into a hypothetical future where energy harvesting technology has improved, and the energy required to power larger, more complex devices has been reduced, possibilities abound. What if a yet-to-be-developed energy harvesting technique could leverage your body heat to extend your phone’s battery life while in your pocket? What if you could power an entire electric, autonomous vehicle with solar panels on the roof of the car? Or by small wind turbines affixed to the outside of the car? Not only would you be reducing your carbon footprint by going electric, but you also wouldn’t have to plug into the grid to charge.
These specific examples, of course, are all hypotheticals and may never be feasible. That said, I think we will see lots of creative solutions to lower energy demands and curb carbon emissions in the coming years. I believe energy harvesting and companies like ON Semi have the potential to play a significant role. We’re just now scratching the surface.
In the here and now, energy harvesting is already a viable solution for ultra-low-power IoT devices, and I believe based on my research that ON Semi is at the forefront of the movement. Offerings such as the Bluetooth Low Energy Switch should allow businesses to save money, increase their efficiency, lessen their environmental impact and likely reap other benefits that will become clear down the line. Additionally, this technology has the potential to enable digital transformation for businesses who previously were unable to afford the associated energy, installation and upkeep costs of IoT infrastructure. Companies must be able to leverage intelligent data analytics to remain competitive in the coming years. Energy harvesting—think about it.
Note: Moor Insights & Strategy writers and editors may have contributed to this article.