NTT envisions a “greener” IoT sensor

This story was originally published in my  Oct. 14 weekly IoT newsletter.

One of the larger challenges associated with the internet of things is e-waste. Every sensor deployed into the world has a cache of heavy, rare metals and hard-to-recycle electronics inside. Yet the promise of using more sensors to help optimize production in factories or track climate change in cities means their benefits outweigh their costs.

But what if the environmental costs of those sensors could be lower? Today happens to be International E-Waste Day, so it seems appropriate to highlight research from NTT and The University of Tokyo’s Graduate School of Frontier Sciences. Together they have produced the world’s first combined battery and a circuit composed of environmentally friendly materials free of scarce elements and hazardous substances.

Neither are even close to being ready for the internet of things yet. But the related research could become the underpinnings of the next generation of chips designed, not with capacity in mind, but with the goal of not harming the environment. Kazuhiro Gomi, the CEO of NTT Research, a division of NTT Corp., says that the device researchers have built is akin to the transistors made back in the 1960s. So we have a long way to go.

NTT Research has created a circuit and a battery connected by wires made of carbon tubes as opposed to copper. Copper is both rare and harmful to the environment in large quantities, whereas this battery is completely recyclable and uses chemicals found in fertilizer to power the transistor.

The transistor itself is what I find so compelling. It replaces the arsenic, copper, tungsten, and other rare and harmful chemicals found in traditional chips with carbon, hydrogen, aluminum, nitrogen, and sulphur. Some of these chemicals are combined into polymides that are similar to plastics but are biodegradable.

The resulting transistors are very low-frequency devices that don’t even achieve a kilohertz of performance. (Chip performance is measured by frequency, with today’s high-performing chips reaching frequencies of multiple gigahertz.) These transistors can’t even generate enough performance to send out a radio signal. Which, by the way, is the next goal of the research team.

But I’m enamored with this project because it represents the beginning of a green revolution for electronics manufacturing. If we can make the basic building blocks of a semiconductor and sensor — the transistors, the wires, the substrate, the batteries — more environmentally friendly, we can shift electronics manufacturing to a much greener path and address some of the harms that we have done to the planet.

When engineers started building semiconductors in the ’60s and ’70s, they optimized for performance and reliability. Jack Kilby and Robert Noyce, the fathers of integrated circuits, were not concerned about environmental damage. But today, we are, and to make the internet of things ubiquitous and less harmful we may have to go back to the beginning to rethink what we want to optimize for.

Gomi says the goal of this research was to create a circuit and battery that didn’t harm the environment. “Can you do it or not? That’s the first question we had, and this invention basically gave us the answer,” he says. “And that answer is yes. Yes, you can.”

With that in mind, I can’t wait to see how this evolves. And I hope it doesn’t take 60 or 70 years to do so.