Wi-Fi Alliance Makes Energy Efficiency Case for Wi-Fi Over Cellular Networks

Allocating the 6 GHz band for unlicensed use can help cut overall energy use relative to using carrier networks, argues a new study by WIK, released by the Wi-Fi Alliance Monday. European nations are considering whether to follow the U.S. lead and allocate the full 6 GHz band for Wi-Fi, and a key decision on the spectrum is expected at the World Radiocommunication Conference, which starts Nov. 20 in Dubai.

Potential energy savings through the wider use of Wi-Fi haven’t been highlighted in the past, said Alex Roytblat, Wi-Fi Alliance vice president-regulatory affairs, in an interview Monday. Everyone is focused on deploying wide-area, or cellular networks, he said. These networks are designed to cover wide areas and have to “push their signals into the homes, into the offices, into the factories” and the signal must be “pushed back to those base stations,” he said.

From an energy standpoint, “that’s an extremely inefficient way to communicate,” Roytblat said. It takes a lot of energy to propagate signals through structures, trees and other obstacles, he said. As data demands increase, energy demands also grow, he said. Most data consumed is also consumed indoors, as people work from home and entertain at home, he said. People rely on cellular networks, “but the majority of our time we spend within the coverage of a local area network, such as Wi-Fi,” he said.

Throughout much of the world, regulators are still discussing whether to allocate the entire 6 GHz band, or just the lower 500 MHz, for unlicensed use, Roytblat said. The FCC dedicated the band to Wi-Fi in 2020 (see 2004230059), but hasn't reached decisions on a Further NPRM to further liberalize the rules (see 2306230046).

Estimates are that more than 400 million Wi-Fi 6E devices, which use 6 GHz, will be shipped in 2023, Roytblat said. “Predictions for future years are staggering,” he said.

“Planned upgrades to 5G mobile networks could further increase the environmental footprint of the network,” the study argues: “In China and Japan, where 5G deployment is the most advanced, the number of 5G base stations required is around 1.4 to two times higher than that of 4G base stations. Research suggests increasing the number of small cells could strain the electric power infrastructure, and the energy consumption of 5G access networks is higher for use cases that require ultra-low latency connectivity” such as augmented and virtual reality.

The study estimates increased energy use of 3.2 megatons of carbon dioxide emissions in Europe per year from cellular networks unless adequate spectrum is provided for unlicensed use by reallocation of the entire 6 GHz band.

“We are trying to provide this data point to regulators around the world with this study,” Roytblat said. Policymakers in Europe and around the world are wrestling with the energy-use issue and the alliance hopes the study will “elevate” the issue, he said.

The WRC will consider whether to identify the upper 700 MHz for international mobile telecommunications (IMT). In the Americas, most nations are opening the entire 1,200 MHz for Wi-Fi, as have South Korea and Saudi Arabia (see [Ref:2302060052). European and other major countries authorized only the lower 500 MHz, as they await consensus at the WRC.

The Americas region will finalize its position at the Inter-American Telecommunication Commission (CITEL) meeting in Ottawa this month, Roytblat said. Most nations in our region are advocating “a firm no change … meaning do not identify for IMT,” he said: “If you choose to use it for any kind of mobile network that’s your decision, but there’s no need to modify the international treaty on spectrum use.”

At the last CITEL meeting in May, delegates already adopted a recommendation against identification and the alliance expects other countries to join this proposal at the upcoming meeting, Roytblat said. Roytblat expects “a strongly supported inter-American proposal coming out of CITEL in August.”