Through Michael Allen
Tiny electronic devices connected to the internet are becoming ubiquitous. The so-called Internet of Things (IoT) enables our smart gadgets in the home and wearable technologies like our smartwatches to communicate and work with each other. IoT devices are increasingly being used across all kinds of industries to drive connectivity and intelligent automation as part of the “fourth industrial revolution”.
The fourth industrial revolution builds on already widespread digital technologies such as connected devices, artificial intelligence, robotics and 3D printing. It is expected to be a significant factor in revolutionizing society, economy and culture.
These small, autonomous, connected, and often wireless devices are already playing a key role in our everyday lives, helping to make us more resource and energy efficient, organized, safe, and healthy.
However, there is a key challenge – how to power these tiny devices. The obvious answer is “batteries”. But it’s not that simple.
Many of these devices are too small to use a long-lasting battery, and they’re in remote or hard-to-reach locations — say, in the middle of the ocean to track a shipping container, or atop a grain elevator to monitor levels of Grain. These types of locations make the maintenance of some IoT devices extremely difficult and not economically and logistically feasible.
Mike Hayes, Head of ICT for Energy Efficiency at the Tyndall National Institute in Ireland, summarizes the market. “It is projected that by 2025 we will have a trillion sensors worldwide,” he said, “that’s a thousand billion sensors.”
That number isn’t as crazy as it first seems, according to Hayes, the coordinator of the Horizon-funded EnABLES project (European infrastructure for the Internet of Things).
If you think about the sensors in the technology that someone wears on their body or has in their car, home, office, as well as the sensors embedded in the infrastructure around them like roads and railroads, you can see he explained where that number came from.
“In the projected world of trillions of IoT sensors by 2025, we will be throwing over 100 million batteries into landfills every day unless we significantly extend battery life,” Hayes said.
Landfills are not the only environmental problem. We also need to consider where all the material to make the batteries will come from. The EnABLES project calls on the EU and industry leaders to think about battery life from the outset when developing IoT devices, to ensure that batteries do not limit the life of devices.
“We don’t need the device forever,” Hayes said. “The trick is that you have to survive the application you are operating. For example, if you want to monitor an industrial device, you probably want it to last five to 10 years. And in some cases, if you do a regular service every three years anyway, that’s probably enough if the battery lasts longer than three or four years.’
Although many devices have an operating life of more than 10 years, the battery life of wireless sensors is typically only one to two years.
The first step to longer battery life is to increase the energy delivered by batteries. Reducing the power consumption of devices also extends battery life. But EnABLES goes even further.
The project brings together 11 leading European research institutes. Together with other stakeholders, EnABLES works to develop innovative ways to harvest tiny environmental energies such as light, heat and vibration.
Harvesting such energies will further extend battery life. The goal is to create self-charging batteries that last longer or ultimately run autonomously.
According to Hayes, ambient energy harvesters, such as a small vibratory harvester or indoor solar panel, that generate small amounts of electricity (in the milliwatt range) could significantly extend the battery life of many devices. This includes everyday objects such as watches, radio frequency identification (RFID) tags, hearing aids, carbon dioxide detectors, and temperature, light, and humidity sensors.
EnABLES is also developing the other key technologies needed for tiny IoT devices. Not content with improving energy efficiency, the project also seeks to develop a framework and standardized and interoperable technologies for these devices.
One of the biggest challenges with autonomously operated IoT tools is power management. The energy source can be intermittent and at very low levels (microwatts), and different methods of harvesting yield different forms of energy that require different techniques for conversion to electricity.
Huw Davies, is Chief Executive Officer of trameto, a company that develops energy management for piezoelectric applications. He points out that the energy from photovoltaic devices tends to come in a steady trickle, while that from piezoelectric devices, which convert ambient energy from motion (vibration) into electrical energy, generally comes in bursts.
“You need a way to store that energy locally at a store before it’s delivered to a load, so you need ways to manage that,” Davies said.
He is the project coordinator of the Horizon funded HarvestAll Project that developed an energy management system for ambient energy called OptiJoule.
OptiJoule works with piezoelectric materials, photovoltaics and thermoelectric generators. It can work with any of these sources alone or with multiple energy harvesting sources at the same time.
The aim is to enable autonomous sensors to be self-sufficient. In principle it is very simple. “We’re talking about extremely low-power sensors that do some digital measurements,” Davies said. ‘Temperature, humidity, pressure, whatever it is, and the data from that is being delivered to the internet.’
The HarvestAll integrated circuit energy management device adapts to the various energy harvesters. It takes the variable and intermittent energy produced by these harvesters, stores it in a battery or capacitor, for example, and then manages the delivery of a constant output of energy to the sensor.
Similar to the EnABLES project, the idea is to create a standardized technology that will enable the rapid development of long battery life/autonomous IoT devices in Europe and the world.
Davies said the power management circuitry is completely autonomous and automatic. It is designed to be easily connected to an energy harvester or a combination of harvesters and a sensor. As a battery replacement, Davies says it has a significant advantage because “it’ll just work.”
The research in this article was funded by the EU. This article was originally published in horizonthe EU magazine for research and innovation.