Andy Pye asks whether the iPhone in your pocket or the refrigerator in your kitchen uses more electricity.
Hard as it might be to believe, the answer is probably the iPhone. A new report by Mark Mills — the CEO of the technology and investment advisory firm Digital Power Group – a medium-size refrigerator that qualifies for the Environmental Protection Agency’s Energy Star rating will use about 322kWh a year. The average iPhone, according to Mills’ calculations, uses about 361kWh a year, once the wireless connections, data usage and battery charging are tallied up (even though it should be noted that there is a significant range in estimates of power use by wireless networks, and that this study goes with the very high end).
Nonethelesss, the information-communications-technologies (ICT) ecosystem, otherwise known as the digital economy, is consuming a large and growing amount of energy. One computer workstation, if not turned off, uses roughly the same energy in a year that it takes a 25mpg car engine to travel more than 4,500 miles. The servers supporting it and its cousins also require enormous energy, as do the systems that heat, cool and light its surroundings.
The global ICT system includes everything from smartphones to laptops to digital TVs to the vast and electron-thirsty computer-server farms that make up the backbone of what we call “the cloud.” Now, it is estimated by Mills that the global ICT system uses 1,500 terawatt-hours of power per year. That’s about 10% of the world’s total electricity generation or roughly the combined power production of Germany and Japan. This is the same amount of electricity that was used to light the entire planet in 1985. We already use 50% more energy to move bytes than we do to move planes in global aviation.
Perhaps even more concerning is the growth of remote digital sensors and devices that are being connected to the internet under Industry 4.0. This, according to Lancaster University researchers, has the potential to bring virtually unlimited increases in energy consumed by smart technologies.
Industry 4.0 removes some of the constraints on the amount of data demand on the Internet – a finite number of people and some limit (theoretically at least!) to the number of hours in the day that each can spend online. But autonomous streaming of data by billions of sensors built into everything removes them. There are currently 6.4 billion connected IoT devices, and it is estimated the number could reach 21 billion by 2020.
“The internet is consuming an increasing portion of global electricity supply, and this growing consumption is a significant concern in global efforts to reduce carbon emissions,” says Dr Mike Hazas, senior lecturer in the university’s School of Computing and Communications.
As our lives migrate progressively to the digital cloud — and as more and more wireless devices of all sorts become part of our lives — the electrons will follow. And that shift underscores how challenging it will be to reduce electricity use and carbon emissions even as we become more efficient.