With the safety and reliability of the electric grid and other critical infrastructure at stake, the Federal Communications Commission should proceed with caution on any plan to commercialize the portion of radio spectrum currently reserved for utilities.

That’s the message the Department of Energy sent this month to the FCC, which is considering opening the 6 gigahertz band to unlicensed users—a move NRECA and electric and water utilities oppose.

DOE acknowledged the FCC is under pressure to make more spectrum available to wireless networks but warned that “secure communications is a mission-critical operational function for the energy and water industries and must be protected.”

“Energy and water systems are dependent and reliant on communications through the use of dedicated and sufficient spectrum,” Assistant Energy Secretary Bruce Walker wrote to FCC Chairman Ajit Pai on Sept. 3. “All the other critical infrastructure sectors, including telecommunications, are also reliant on the energy sector.”

NRECA commended DOE for its support on the issue.

“We are very pleased DOE shared its concerns with the FCC. It highlights the immense impact this proposal could have on the safety and reliability of the electric grid,” said Brian O’Hara, NRECA senior director of regulatory affairs.

NRECA, American Public Power Association, American Water Works Association, Edison Electric Institute and Utilities Technology Council earlier this year raised deep concerns to the FCC about its proposed 6GHz order.

DOE noted that systems suggested by FCC to control interference between licensed utilities and unlicensed users of the band are either untested or have failed to work properly on other bands.

Walker said FCC should “investigate a long-term solution for dedicated spectrum for our critical infrastructure users in the energy and water sectors.”

“This is necessary with the anticipated significant expansion of WiFi usage and the potential for near- and long-term spectrum interference in the 6 GHz band,” he said.