Tech Tips: Home Energy Harvesting

March 4, 2023

Energy harvesting has long been a utopian goal of the smart home. A quick Google search will reveal IEEE studies dating back to the mid-2010s touting solar cells and thermoelectric generators as power sources for wireless sensors. It explains why companies like ADT, Alarm.com and Vivint have expanded into solar, and why companies like Schneider Electric put smart energy management at the forefront of their Consumer Electronics Show (CES) messaging. The 2023 CES was held Jan. 6-8 in Las Vegas.

A critical element in making smart home sensors and devices easy for homeowners to adopt is making them easy to power – whether that means they draw little power or they harvest power in some other way. In fact, battery life is one of the major barriers to entry for many smart home products – especially smart locks. Search reviews for all the top smart locks on Amazon or Home Depot or Lowes, and a common refrain reads something like this: Be prepared to go through a lot of batteries. There is no low battery warning either, so you better hide a key somewhere outside.

Thankfully for smart lock manufacturers, several startup companies are looking to end this dependence on batteries. Enter New York-based WePower Technologies, which came out of stealth mode to unveil its innovative energy harvesting technology at CES 2023.

Founded by long-time consumer technology executive, investor, and Consumer Technology Association (CTA) heavy-hitter Larry Richenstein, “WePower has pioneered a groundbreaking way to harvest kinetic energy using electromagnetic induction to power wireless sensors and related devices at a significantly higher voltage level than other kinetic EHG solutions, thereby eliminating the need for the cost, weight, maintenance, and disposal of the billions of cell batteries that are produced and discarded each year,” its website says.

I had a chance to sit down with Richenstein at the show, who explained further how the technology works, and if there can truly be a world with no smart lock battery replacement.

“We harvest energy from motion,” he said. “We have generators, and we also have energy harvesting circuits that take that energy [from motion], put it into capacitors, so they are ready for use for wireless transmission and sensors.

“When we look at smart locks, the advantage is that we have motion – every time you open the door and close the door [turn the handle],” Richenstein added. “There is a way where we can harvest that motion and energize a smart lock. We can do this from the standpoint of when the door opens and closes … there are a lot of different ways to harvest energy from motion. Our energy harvesting generators will ensure that the signal that you are sending is going to go throughout the smart home and really get the signal there in a robust fashion so that it's reliable and completely received.”

Richenstein said he is confident that such a technology will eliminate the need to replace batteries in smart locks in the future. “The locks are an easy [use-case] because of that movement [of opening and closing the handle], and I believe we can apply it to any of the smart locks.”

How it Works

The technology uses electromagnetic induction, which is the process of creating an electrical current by moving an electric conductor through a static magnetic field. The device Richenstein demonstrated is about the size of a walnut, and it uses permanent magnets to create oscillation from any motion (such as a push of a button or turn of a door handle), which, in turn, creates an electromagnetic current – an ongoing energy source – through a copper coil.

An energy harvesting circuit pulls this kinetic energy from the module, and processes and stores it in the circuit’s capacitors. This energy is then used by sensors and transmitters to send long-range, high-reliability transmissions without the need for batteries or wired power.

“We need motion; we need some movement,” Richenstein explained. “In the future as this technology develops, but I know that you know going forward we're going to find new ways to activate the generators themselves. What we have been seeing when talking to [manufacturers] for the first time at this show, is that people really want to understand how it is activated, and there are so many different ways to do it.”

WePower’s business model, according to Richenstein, is to supply manufacturers with the technology to enable them to build it directly into end-products, such as smart locks. 

“This is really agnostic. We make the generator, we also have a circuit that takes that power, because it is not a trivial thing to take the energy from one of these generators and put it in a capacitor,” Richenstein explained. “That's really our point of demarcation. We have capacitors at the end of that circuit, and now people can connect to that wirelessly – Z-Wave, Bluetooth, Thread, Matter, whatever.

“The opportunities are there,” Richenstein added. “The alarm companies, the big ones, might be interested in putting this into their hardware. I think that once [manufacturers] start with the first one of these, they are going to start to think about how else it can be used. Then we are going to start to see some really exciting new solutions.”

Learn more about WePower at https://wepowertechnologies.com.