Powering up the future
THE ENERGY DEBATE IS HOTTING UP IN AUSTRALIA, YET RESEARCHERS ARE FINDING ENERGY FROM ALMOST ANYWHERE. TECHLIFE INVESTIGATES THE TECH THAT COULD POWER YOUR FUTURE.
TORNADOS ARE NOT uncommon in the southeastern regions of South Australia. You wouldn’t exactly call it ‘Tornado Alley’, but the Bureau of Meteorology does consider the area one of Australia’s more likely locations for twisters to touch down. Yet when two tornados 170km apart ripped through the area during the afternoon of September 28th, 2016, taking down high-voltage electrical transmission lines, the ramifications of the state-wide blackout that followed are still being felt today. No matter where you stand on the ‘renewables vs fossil fuels’ debate, our evergrowing reliance on tech has created an equallyinsatiable demand for energy. While governments and businesses determine how best to create that energy on an industrial scale, research underway today could revolutionise the way we power much of our tech in the future — and generating that power could involve you more than you expect.
SOUTH AUSTRALIA’S TESLA BATTERY
Australia is currently working through modernising its energy generation capability, but nothing seems to drive governments to action as fast a state-wide electricity blackout. However, as the wheels of government began to turn after the September 2016 event, it was ultimately a Twitter conversation between Atlassian co-founder Mike CannonBrookes and Tesla boss Elon Musk that kickstarted plans for Tesla to build what would be the world’s largest Lithium-Ion battery in South Australia. Musk has had his hands full churning out his new Model 3 electric car, but that didn’t stop him signing on the dotted line with the state government to build the battery, even going as far as declaring on Twitter that it would be built and ready to go within 100 days or it’d be free. In the end, the battery, with a rumoured $50 million price-tag, was online a day ahead of schedule, storing energy from the nearby Hornsdale wind farm at Jamestown in the state’s north within its cells. The battery itself is reportedly capable of delivering 100-megawatts (100MW) of electricity and stores 129-megawatt-hours (129MWh) of energy — meaning that at full tilt, the battery will stay up for around 75 minutes and supply electricity for up to 30,000 homes.
Would it have prevented the September 2016 blackout? Not even the experts can seem to agree on an answer for that one. The Tesla Battery hasn’t won universal praise within the ranks of government; however, South Australian premier Jay Weatherill is confident it will help keep the electricity grid in balance and reduce the risk of future state-wide blackouts.
ENERGY HARVESTING
While the energy requirements to charge car battery systems and power air conditioners are substantial, the rapid miniaturisation of electronics over the last 50 years has meant power needs elsewhere have fallen dramatically. The first all-electronic computer, Colossus, would’ve needed almost the equivalent of a small substation to power back in 1944. Today, ARM Cortex-M micro-computer or
‘microcontroller’ chips drive your smart fitness band with many times more computing power than the Colossus on the equivalent of a coinbattery. Atmel, the tech company that makes chips powering the popular Arduino maker boards, has a microcontroller chip called the SAML21 that has a power consumption so low, makers talk of its potential runtime on a single battery not in hours or years, but in decades. Microcontroller chips are the brains behind many of the Internet of Things (IoT) devices hitting the market, so as the number of chips in use continues into the billions, the individual power requirements of each new chip generation shrinks. This continuing trend has encouraged research into more unusual sources of energy that don’t come from a traditional wall socket or battery.
YOU’RE THE SOURCE
As governments and industry sort out electricity generation on a national level, researchers are looking at generating energy on a much more personal level. If you have young kids running around your feet, you’ll know already that the human body is a bundle of energy. Our brains send and respond to small electrical pulses that drive our hearts to pump blood and our nerves to feel pain. Health professionals have been telling us for years we all need to move more — that movement itself is a release of energy and its being actively researched as a source of power for a growing array of sensors and e-health technologies.
For example, researchers at the Swiss Federal Laboratories for Materials Science and Technology (known as ‘Empa’) have taken the concept that made music records possible for 100 years and turned it into a thin flexible film capable of generation electricity. Called the ‘piezoelectric effect’, it originally enabled a record player to turn the lateral movement of a needle following a record groove into an electrical signal that, when amplified, provided generations of music from Glenn Miller to Elton John. This new organic film creates small amounts of electricity whenever the film is stretched or compressed, with Empa researchers believing it could be implanted into clothes to harvest energy. There’s even thought it could one day be used to harvest energy from a human heartbeat to power pacemakers (
Yet, these ‘piezoelectric nanogenerators’ (PNGs) are being created from even more unusual materials. The Indian Institute of Technology (IIT) has developed a bio-PNG made from — of all things — onion skins. The prototype developed 18 volts at 166 nanoamps for a power density of 1.7 microwatts per square-centimetre and requires only very low-pressure movement. IIT researchers have even successfully used the onion power source as a way of detecting speech signals, opening up the way for speech recognition in the future ( tinyurl.com/ y6wnwbjc).
TRIBOELECTRIC NANOGENERATION
Still, thin-film piezoelectric power generation isn’t the only area of research for harvesting human energy. You can generate small amounts of energy by stressing piezoelectric-enabled materials, but you can also do likewise rubbing dissimilar polymer materials together. It’s called ‘triboelectric nanogeneration’ or 'TENG' and its being researched for a range of applications.
In South Korea, researchers at the Ulsan National Institute of Science and Technology recently developed a polymer material that significantly boosts the energy output of TENGs. While that energy output is still comparatively low by smartphone standards, UNIST scientists hope to eventually show a TENG charging a smartwatch (
Meanwhile, researchers at China’s National Center for Nanoscience and Technology have developed a TENG that has a skin-like form. Combining a polymer with high elasticity called an ‘elastomer’ with a water-based gel
or ‘hydrogel’, the research team has developed a TENG capable of generating 35 milliwatts of power per square metre. The material is also said to be virtually transparent.
No one is making predictions on when it will happen just yet, but whether they incorporate piezoelectric or triboelectric nanogeneration, you could one day end up buying a pair of Nikés that charge your phone as you go for your morning run.
BATTERY-FREE MOBILE PHONES
For now, though, it seems the energy generated by these nano-scale methods would struggle to blow the foam off your latte, but as the scale of electronics manufacturing reaches down to atomic level, the energy required for next-gen devices will be even less.
We’re all used to the daily grind of charging smartphone batteries overnight ready for the next day’s workload, but at the University of Washington, scientists have designed and built the world’s first battery-less mobile phone. By harvesting power from a mixture of radiowaves and ambient light, researchers have been able to create a phone able to make wireless Skype calls over a cellular network. The phone consumes just microwatts of energy or roughly in the order of one-millionth of the energy consumed by a typical phone ( tinyurl.
com/ycq49t87). It’s also only at the ‘proof of concept’ stage, so don’t hold your breath for a battery-less iPhone. Still, the fact battery-less phone calls are even possible is still pretty cool.
INTERNET OF THINGS
While battery-less phones might still be a while away, what you will see plenty of in the near future is battery-less and wire-less sensors slotting into the IoT network. As businesses increasingly turn to data analytics to try and find that next commercial edge over their competition, it’s the almost irresistible combination of cheap, low-power microcontroller chips generating oceans of data that really drive the IoT market. As a result, much of the work going into energy harvesting will likely be applied to IoT sensors, as researchers seek ways to avoid the weight and added complexity of servicing rechargeable batteries.
Already, companies such as EnOcean have developed ‘self-powered IoT’ devices, wireless transmitter and receiver modules that operate at various frequencies up to 2.4GHz and harvest the energy that powers them from nearby radiowave sources ( tinyurl.com/y8fax26u). EnOcean is also currently working with IBM on ‘cognitive buildings’, buildings that automatically gather data from an array of built-in sensors, mine that data for information and use it to automate the internal environment — think of it as artificial intelligence for buildings ( tinyurl.com/y8qpsu5d).
SMART WINDOWS
Solar farms are typically set up out in the middle of nowhere surrounded by little more than sunlight, and although the land put to solar farm use is proportionally small on the grand scale of things, it’s still commonly measured in ‘football field’ dimensions. Nevertheless, with tower blocks and homes filling up city landscapes, there’s growing research into ‘smart windows’, windows that not only switch from clear to tint in the presence of sunlight, but can also turn that sunlight into electricity.
The National Renewable Energy Laboratory at the US Department of Energy has recently developed a smart window with 11.3% solar conversion efficiency. It’s far from the current record solar efficiency level of 46%, but still more than enough to be useful. However, while the new technology, built around carbon nanotubes, shows early promise, the process of molecules switching between clear and tint reportedly causes degradation in power output noticeable
in only 20 switching cycles. Still, its potential to offset rising electricity costs will ensure continued research ( tinyurl.com/y7arce4t).
SMART WALLPAPER?
If you think windows are as smart as building products get, think again. As we’ve already seen, there’s significant demand right now to incorporate IoT tech into new buildings for automating standard infrastructure features such as heating and cooling, but research isn’t limited to what’s happening behind the walls. London’s Imperial College has taken that home decorating staple — wallpaper — to a whole new level. Researchers have figured out how to take cyanobacteria, tiny microorganisms that can photosynthesise light, and turn them into an ink that can be printed by an inkjet printer onto paper. What makes this even more useful is that they can also print electrically conductive carbon nanotubes onto the paper using the same process. By first laying down a layer of nanotubes and printing cyanobacteria on top, the bacteria photosynthesise light and generate small amounts of electricity that can be harvested. While we wouldn’t suggest you expect your next lounge room reno to start paying your electricity bills any time soon, Imperial College’s Dr Marin Sawa sees this disposable bio-battery having applications for temporary sensors, such as measuring home air quality. Once the sensor has done its job, it can be left to bio-degrade with no environmental impact ( tinyurl.com/yd8ne2cv).
AUTOMOTIVE ENERGY HARVESTING
The car market may well be heavily focused on autonomous driving at the moment, but it isn’t the only smart tech game in town for car makers. As electric cars continue development, methods for converting kinetic energy back into electricity gather pace. Already, Tesla cars use the relatively mature concept of regenerative braking, where, in this case, the AC induction motor driving the car uses the torque created by braking to reverse-generate electricity that charges the batteries.
However, according to research analysts, the automotive energy harvesting market is set to sky-rocket from just under $26 billion in 2016 to a handsome $105 billion by 2023. While regenerative braking is already being used, more advanced technology including exhaust gas recirculation and turbocharger tapping are being researched as sources of reusable energy.
Lamborghini is even going so far as to use the whole carbon fibre body of its new ‘Terzo Millenio’ concept electric sports car to not only store energy, but to also incorporate self-healing capabilities. The Italian supercar maker is working with the Massachusetts Institute of Technology (MIT) to further the use of supercapacitors as power storage devices within its cars, while also working with scientists to create new carbon-fibre materials that can auto-detect and self-heal cracks via internal chemistry ( tinyurl.com/ybl7wlqh).
THE ENERGY IS OUT THERE
If nothing else, it all highlights just how much renewable energy is out there — from wind, solar, thermal and tidal right down to piezoelectric, triboelectric, radiowave and even photobacterial energy harvesting. Provided artificial intelligence doesn’t eventually go the way of The Matrix and see us all as just distributed power sources, much of the energy you use in the future could be energy you make, drive or wear.
Now if we could figure out how to harness the power inside a tornado...
HEALTH PROFESSIONALS HAVE BEEN TELLING US FOR YEARS WE ALL NEED TO MOVE MORE — THAT MOVEMENT ITSELF IS A RELEASE OF ENERGY AND ITS BEING ACTIVELY RESEARCHED AS A SOURCE OF POWER FOR A GROWING ARRAY OF SENSORS AND E-HEALTH TECHNOLOGIES.