Lord Drayson, CEO, Drayson Technologies, examines how energy harvesting technologies offer the opportunity for IoT devices to run continually, without the need for battery changes.
Wireless energy transfer has gone through numerous exciting iterations since Nikola Tesla’s early experiments at the turn of the 20th Century. Now, as we enter the age of connected devices, energy harvesting technologies have progressed to the point where low-energy devices can be powered perpetually – opening up revolutionary new applications.
Smart cities and healthcare IoT deployments are just two examples of areas where connected devices, such as sensors and beacons, are providing economic and social benefits, improving the lives of the public. A recent report has found that the healthcare IoT sector is expected to grow at a CAGR of around 37 per cent by 2020, driven largely by wireless patient monitoring systems. Such systems allow hospitals to better manage free beds, all the while collecting patient data that can assist with treatment. Meanwhile, IoT deployments in cities, such as Drayson Technologies’ CleanSpace – the air pollution monitoring network – are collecting data of value to the public as smart cities start to build a smarter society.
This is where energy harvesting can assist with such innovative deployments. As more and more devices enter the market, and numerous areas of industry and business utilise the IoT, the sheer amount of data being collected will increase monumentally. For organisations, it therefore becomes imperative to manage the costs associated with the installation, maintenance and operation of the hardware, whilst also efficiently managing the collection, analysis and reaction to the data being collected.
How does energy harvesting work?
Certain energy harvesting systems, such as photovoltaic or thermoelectric systems, have inherent limitations such as moving parts, fragility, and the requirement of a constant energy source. However, radio frequency (RF) waves present the best option in many scenarios for energy harvesting to power low-energy IoT devices. RF waves are being generated all around us, at different levels, all the time, in the form of broadcast data to receivers from televisions, smartphones or laptops.
Drayson Technologies’ Freevolt harvester consists of an antenna and associated circuitry that harvests RF energy from the carrier waveform of wireless networks, including 2G, 3G, 4G and Wi-Fi, as well as digital TV broadcast transmissions. Fitting a connected device with Freevolt means RF signals are converted into direct current power. This power then trickle charges energy storage devices, such as batteries or super capacitors, in order to operate low-energy devices.
Smart IoT data collection
It isn’t just the energy required for the hardware to operate that needs to be considered. As sensors collect data, it needs to be accessed from a separate location. These data collection needs to be cost and energy efficient, if you consider an IoT network might have hundreds or thousands of devices forming it. The CleanSpace air pollution network, the first commercial application of Freevolt, uses machine-learning to enhance and control data collection, with sensors called CleanSpace Tags collecting data and feeding it into a crowd-sourced map of air pollution. The system identifies how a user carrying the sensor is moving in order to either increase or decrease the number of readings taken, bolstering the map where required.
Such streamlined approaches to data collection allow greater cost efficiency and data management. As more of our lives, and business operations, become connected through smart devices, we’re going to see an exponential spike in data collection. In order to maintain this growth in a cost efficient way, organisations need to use intelligent systems that collect data at a low level of power consumption. The IoT is here to stay and growing rapidly. It isn’t singular and every single device on a network needs to be evaluated – from every byte of data onwards.
Lord Drayson is CEO of Drayson Technologies