This is a good time to be excited about wireless technology that doesn’t require batteries. As a flush of recent news proves, energy-harvesting technology is poised to move from pilot applications to scaled out use in the real world in the coming year.
If we want to deploy trillions of connected sensors, we have to dump batteries. After all, building batteries for the IoT is limiting: They require chemicals to manufacture, people to change them, and are ultimately a toxic form of waste inside an obsolete product. Thankfully, several startups are now reaching production deployments of their technology, proving that energy harvesting is possible while providing architectures to make it work.
First up is 10-year-old Everactive (formerly known as PsiKick), which has built a system of sensors that harvest their own energy to track vibration or temperature changes. It recently placed those sensors in 12 Anheuser-Busch breweries, on steam traps used for making beer. The sensors use the heat generated by the steam to monitor how well the steam traps are performing.
It’s the largest deployment of Everactive’s sensors to date, and while the beer maker has only put the sensors on a quarter of its steam traps, doing so has already helped it save 7,561 tons of carbon. The amount of energy saved is about 1.2% of its overall energy use, but every little bit helps.
Notably, the reason this application became a real-world use case was because Everactive’s sensors don’t require ongoing battery changes. According to Barkley Edison, a steam systems subject matter expert with Anheuser-Busch, the brewer spent the last 10 years searching for a steam trap-monitoring product before finding Everactive’s sensors. In a case study for Everactive, he said it can cost $500-$1,000 to replace a single battery, and since a single plant may have hundreds of steam traps, those costs are untenable.
Everactive’s sensors are now deployed in production environments at scale, but other energy-harvesting sensor makers are still gearing up for scale. Among them is Wiliot, which this week announced a partnership program that will bring its energy-harvesting, stamp-sized Bluetooth tags to more industries. The move is part of an overall shift in strategy for Wiliot, from selling its tags to letting other companies manufacture and sell them. Wiliot, meanwhile, now makes money selling cloud services to connect the tags.
In the last few months, Wiliot has scored deals with several RFID companies to manufacture the Wiliot Pixels, which they will then seek to move through their traditional sales channels. “We’re co-opting an industry that’s already making 20 billion to 30 billion IoT devices and replacing it with something that has much more utility and privacy,” Steve Statler, the head of marketing for Wiliot, told me in an interview.
Each Wiliot tag uses Bluetooth to share sensor and location information about whatever it is stuck onto. The tags can be used to track everything from large items like pallets in a warehouse to small individual items in a store. Without batteries, they are cheap, and it’s easy to deploy thousands of them.
Not to be outdone, a chip company that has taken some of the complexity out of building devices capable of harvesting energy has announced its second-generation chip. Nowi, a Dutch company, in late March launched its Diatom module, which does both the energy harvesting and the associated power management to deliver that harvested energy to the device. Because harvested energy tends to get delivered in bursts vs. a steady stream, companies that wanted to harvest energy often had to make complex calculations about how to deliver it.
Nowi’s integrated module handles the scaling up and down based on incoming energy for the hardware designer. This will make it easier for more companies to deploy energy-sensing capabilities into their devices, though Nowi’s module is a bit different from the likes of Wiliot or Everactive, which have designed specialized chips to harness energy and employ the maximum amount for sensing. Plus, while Nowi’s more generalized approach may lead to some leakage, the company is betting that the ease of implementation will broaden the overall number of use cases and with it, the market.
Finally, just for fun, I wanted to also include a recent deal between Atmosic, another company building energy-harvesting Bluetooth radios, and Energous, a company that delivers over-the-air wireless power. The two have teamed up to build a development kit for engineers who might want to use over-the-air wireless power.
In many cases, devices that use energy-harvesting technology still have batteries that can store harvested energy, much like you’d use a solar panel to charge a battery for use when the sun goes down. You might not have to change the battery, but it’s there. The deal with Energous makes use of a battery by not only taking in harvested energy, but by using over-the-air wireless power provided by Energous’ transmitter.
For more on over-the-air wireless power, check out my recent podcast interview with Doug Stovall, CEO of Ossia. Last month, Ossia received FCC approval to deliver 5 watts of power to devices over the air. This is yet another way to avoid replacing batteries or recharging devices on a charging stand or with a cord.
In light of the momentum associated with energy-harvesting technology and a few new advancements in over-the-air wireless power, it feels like we’re on a way to battery-free future for sensing. I cannot wait.