DGFI has commercialised a small, inexpensive, wireless sensor that’s helping solar power researchers around the world. 

UNSW Digital Grid Futures Institute (DGFI) has helped commercialise an inexpensive, standalone, wireless sensor that is helping solar power researchers around the world.

Who wouldn’t want to forgo filling up at the servo in favour of a car whose fuel literally falls freely from the sky? The prospect of widespread adoption of electric vehicles (EVs) within the next decade has prompted Associate Professor Ned Ekins-Daukes to consider the feasibility of significantly powering those vehicles from the sunlight that falls upon them. 

The question at the heart of this opportunity is just how much fuel really does fall from the sky. To find some answers, Ekins-Daukes and UNSW Digital Grid Futures Institute worked to develop and commercialise a product that has now been implemented around the world. The Solar Jinie is a small, autonomous, solar-powered sensor that can measure the amount of solar radiation hitting any surface – even a moving surface such as that of a vehicle – and transmit that information wirelessly. Far cheaper than anything previously on the market, it has enabled researchers to understand how much solar power may actually be generated if we put solar panels on cars, buses and other transport. “Its aim is to make measuring the intensity of sunshine on any surface easy, so that then you can make a decision, does it make sense to put a solar panel here?” Ekins-Daukes says.

The road to commercialisation

With seed funding from the UNSW DGFI, a start-up company called Enerjin was founded to manufacture Solar Jinies. They have been sold to help researchers solve real-world problems as society moves towards a more sustainable future. Any automotive company navigating the rapid transition to EVs has a lot to think about and the Solar Jinie can help them quickly quantify the benefit that adding solar power to the vehicle will bring. Although EV uptake in Australia has been slow, the abundance of sunshine makes us particularly well-suited to solar-powered EVs. These might just be the product that gets Australia firmly on track with the electrification of road transport.

“Our first finding is one that everyone already sort of knows – that passenger vehicles get used about 3 per cent of the time – 97 per cent of the time they are stationary,” Ekins-Daukes says. “So the amount of energy a car receives depends very much on where it is parked.”

The sensors on buses in western Sydney showed that the bus roofs received almost as much sun as was measured by nearby, stationary meteorological stations. “If the sun is strong, the chances are that bus roof is going to be a pretty exposed location,” Ekins-Daukes says.

But looking further into the future, Ekins-Daukes isn’t just focused on how individual vehicles will power themselves, but how such vehicles en masse could provide a power source of their own. “What could happen in an airport carpark where there’s acres of parked cars?” he asks. “You’ve gone away for a two-week holiday. First of all, you come back and your car is fully charged, but you could also plug those vehicles in and suddenly that carpark is an enormous energy generator and battery storage, with 5000 cars with solar panels. Once the electric vehicles have charged themselves, that power could be available together with a vast distributed battery just sitting in the carpark. That’s when these pieces of the jigsaw start to fit together.”

Future proofing for an electric world

Ekins-Daukes, who is Associate Professor in the UNSW School of Photovoltaic and Renewable Energy Engineering, says the UNSW DGFI brings together various disciplines across UNSW, including engineering, materials science, and social and political sciences, to develop technology and build the knowledge needed to transition to a fully digital grid. He acknowledges that practical, solar-powered EVs are in the same position that EVs were a decade ago – expensive prototypes exist but are very rarely seen on the road. Trials so far with panels on vehicles have only generated small amounts of power, enabling most normal vehicles to travel only small distances. However, as most passenger vehicles travel less than 30km a day on average, such power generation could still be very valuable. “For most of my 20 years, the cost of photovoltaic cells has been the limiting factor. Now the cost is so low, the question has become what else can we do with it? Putting solar cells on vehicles is something we can do quite quickly.”

In addition, he and other researchers are investigating stacking solar cells on top of each other, to generate more power out of a smaller area, with different layers made out of a range of materials to use more parts of the light spectrum. “Nature permits us to make solar cells with four times the efficiency of the present technology so there is a lot more progress that the solar industry can make,” says Ekins-Daukes. In the same way that a smartphone with the power of a supercomputer was unthinkable just a few decades ago, we will likely look back in a decade or two and be similarly astonished with how far solar energy efficiency has progressed.

Some researchers who have bought the sensors have used them to measure solar radiation falling on the sides of buildings. These levels can be affected not just by the height of nearby buildings, but by the colour of nearby facades. The sensor can be slightly adapted to the needs of each client to, for example, record temperatures as well as solar radiation, if required.

“When this kind of science at universities gets coupled with industry, that’s when really exciting technology develops,” Ekins-Daukes says. “It opens our eyes to the things that are possible.”