Of course, we are all excited about the billions or even trillions of Internet of Things (IoT) devices that are quickly taking over our lives, but at some point, we must realize that the exponentially growing deployment of all these smart devices, sensor systems, wireless sensor networks (WSN), Industrial IoT (IIoT) solutions, etc. is still beholden and limited to available energy for the system. Today, the energy source for most of these devices is a battery (as most are not off-line applications or plugged into a wall power source). Even worse, these batteries are mostly primary cells, which mean they are non-rechargeable, contain hazardous materials, end up in landfills, and must be replaced in many applications, which can be quite expensive. Replacement costs can easily dwarf entire system costs by orders of magnitude.
When you ask many people about energy harvesting (EH), there are two main misperceptions: 1.) EH can only produce a negligible amount of power; & 2.) There is no production ecosystem for EH solutions. As one who has spent years investigating this and given the better part of 100 talks on the topic to-date, I can assure you these can be quickly dispelled when approached from the proper perspective so let us address these now. The concern about availability of necessary power can be addressed in many ways with proper, system design philosophies. A key concept to internalize is EH is not an all or nothing proposition so there can be great value in supplementing primary battery life even if not a complete replacement. Another important point here is most system power budgets are much larger than they need to be. The reasons for this are an entire topic that we will not take time to explore here, but the takeaway message is that designers may often be surprised by just how much functionality can be accomplished with so little power (as opposed to the perpetual quest for a bigger battery).
The existence of the EH production ecosystem is what seems to be lacking the most awareness. From the harvesting transducers to the power management integrated circuits (PMIC) to the energy storage devices and so on, there are solutions in all categories as laid out by figure 1 below. Furthermore, ecosystem suppliers range from Tier 1 all the way down, so it is neither purely academic nor solely startup contributors. For instance, the top power semiconductor companies on the planet have had production solutions deployed for well over a decade now.
The biggest gap seems to transcend knowledge of the EH ecosystem, but rather is rooted in the highly compartmentalized nature of its elements. In other words, even many players in the EH ecosystem were unaware of the collaborators, competitors, and even competitors they needed to develop synergies with to perpetuate the ecosystem as a whole and enable all the fantastic marketing projections for the IoT and related industries. Figure 2 expands upon the previous figure to identify some of the most critical contribution areas of expertise that map mostly to the stakeholder groups.
So now that we have identified an EH ecosystem, populated it with key contributors, and informed those contributors of each other’s existence, where do we go from here? We now must execute on the convergence of all the marketing hype with the production ecosystem to support it and adjust on both sides of the fence accordingly. To learn more about this, please attend a full-day, pre-conference symposium on “Designing for Energy Harvesting & Energy Efficiency - Tutorials” on Tuesday, June 25, 2019 at the Sensors Expo & Conference.
The symposium will close with a tutorial titled “The Value of Energy Harvesting for IoT & Existing Ecosystems” by Brian Zahnstecher, Principal of PowerRox, and a pioneer of the EH ecosystem as well as industry-leading expert in system design and applications. More information can be found from the schedule.
About the author
Brian Zahnstecher is a Sr. Member of the IEEE, Chair of the IEEE SFBAC Power Electronics Society (PELS) awarded 2017 Best Chapter awards at the local/national/worldwide levels concurrently (an unprecedented achievement), sits on the Power Sources Manufacturers Association (PSMA) Board of Directors, is Co-founder & Co-chair of the PSMA Reliability Committee, and is the Principal of PowerRox, where he focuses on power design, integration, system applications, OEM market penetration, market research/analysis, and private seminars for power electronics. He leads Power for the IEEE 5G Roadmap Applications & Services Working Group, authored the Group’s position paper, and has lectured on this topic at major industry conferences.
He has successfully handled assignments in system design/architecting, AC/DC front-end power, EMC/EMI design/debug, embedded solutions, processor power, and digital power solutions for a variety of clients. He previously held positions in power electronics with industry leaders Emerson Network Power (now Artesyn), Cisco, and Hewlett-Packard, where he advised on best practices, oversaw product development, managed international teams, created/enhanced optimal workflows and test procedures, and designed and optimized voltage regulators. He has been a regular contributor to the industry as an invited keynote speaker, author, workshop participant, session host, roundtable moderator, and volunteer. He has over 15 years of industry experience and holds Master of Engineering and Bachelor of Science degrees from Worcester Polytechnic Institute.