Engineers from the University of Glasgow have developed a prototype of a digital tool that can monitor and manage phantom load, the electricity consumed by devices such as computers or office equipment when they are plugged into mains power but are not in active use.

Adopting digital-twin technology to manage the power consumption of idle devices could save organisations thousands of pounds a year and help reduce their carbon footprint, research suggests.

Previous research has shown that up to a third of the electricity used in office buildings can be accounted for by phantom power. The research team from the university’s James Watt School of Engineering set out to use their expertise in digital-twin technology to develop a more intelligent, behaviour-adaptive approach to managing the phantom load.

Digital twins are dynamic, data-driven virtual models designed to represent complex adaptive systems. Using smart sensors, they continuously capture real-world data on variables such as electricity use, enabling real-time insights and predictive capabilities.

The team’s system draws data from a network of smart energy sensors, which send information on electricity to a central server using the LoRaWan protocol.

The server uses fuzzy-logic algorithms to identify power usage patterns, and can identify when a device is actively being used and when it’s drawing phantom power.

When the system detects prolonged idle periods, it sends users a prompt on their screen to determine if they’re conducting remote work or running background processes.

This approach aims to raise user’s awareness of their device’s idle periods, perhaps encouraging them to make more careful use of their devices, while preventing legitimate work processes from being cut off. If users don’t respond, or confirm the device isn’t needed, the system can automatically switch off the equipment, cutting off its phantom load altogether. The system can also draw the data it gathers to make predictions about the likely electricity consumption of devices for the next day.

The team’s research was presented as a paper at last week’s IEEE’s international Globecom conference in Taiwan.

Ahmad Taha is leading the work with his team Yuwen Wang, Zhihong Xu and Shilong Yan.

“I’m a firm believer in the idea that that small, collective actions on climate issues can have big effects, and phantom power use is an obvious candidate for that kind of action,” said Taha. “The edge-enabled digital twin system we’ve developed is designed to help organisations reduce their power waste in two different ways. Firstly, it can help identify power management efficiencies in real time, cutting power consumption and reducing carbon emissions. Secondly, by reducing devices’ use of electricity, it could help reduce the need to replace older devices with newer, more power-efficient ones. That in turn could help organisations save on equipment costs in an increasingly challenging economic environment.”

The team validated the potential of the tool by applying it to a lab at the University of Glasgow (www.gla.ac.uk) that is home to workstations connected to more than 30 power-drawing devices.

The paper shows that using the tool in the lab reduced the total power consumption of the workstations by around 40% each week by carefully managing their electricity use. The team estimate that the tool, which uses 27 rules to optimise its decision-making, could reduce total phantom load by 82%, saving the university around £9000 in electricity costs every year if used full time across the university.

“This is a really encouraging result, even applied to a small fraction of the devices around the university’s campus,” said Taha. “It suggests that there could be huge savings to be found by applying digital-twin technology to help tackle the phantom power problem. Reaching net zero will require a broad-spectrum approach to energy monitoring, and this tool could be a valuable part of wider institutional approaches to minimising their carbon footprint using digital twins to monitor variables like occupancy and temperature control. We’re working to investigate how this tool could play a role in the university’s wider efforts to achieve net-zero by 2030, and we’re keen to explore in parallel how it could be used in other universities, businesses and even in homes in the years to come.”

Yuwen Wang, Zhizong Xu, Shilong Yan, Muhammad Ali Imran and David Flynn of the James Watt School of Engineering (www.gla.ac.uk/schools/engineering/) co-authored the paper.