off the grid
adj. Relating to a person, family, dwelling, or community that no longer requires connections to utilities, especially the electricity and water supplies and the sewage system.
Also Seen As
The Earthship dwellers live "off the grid" of any sort of utility, just like the pueblo Indians. Their homes use solar and wind power, and water is collected from rain and snow melt. The dishwashing and bathtub water is used to flush the toilet. Sewage is treated on site and then used to fertilize the crops and landscaping.
—Louann Dorrough, “Sacred grounds,” The Times-Picayune (New Orleans), August 18, 2002
Frank Moran and Terri Crain . . . built a timber and glass cabin in the woods because they didn't want a typical suburban lifestyle. But they enjoy another benefit: They never have to pay a utility bill.

In fact, their house is not hooked up to a utility. Most of the energy to power lights and appliances comes directly from the sun, captured by photovoltaic cells and stored in banks of auto-size batteries. They heat the house with a wood stove and cook with propane. Water is pumped from a nearby well.

They live comfortably, they say, without being hooked up — or in hock — to a utility company. Moran and Crain are not alone. They are among a small, but growing, number of Americans who live "off the grid."
—Terri Shaw, “Utility-Free Living,” The Washington Post, February 27, 1992
1991 (earliest)
But by instituting conservation measures such as using fluorescent bulbs instead of incandescent, and unplugging the VCR when it wasn't in use, they trimmed down to 50 kilowatts a month, and will save more when they get a new energy efficient refrigerator. With a little more conservation and three more solar panels, Guiles thinks he can eventually "get off the grid" entirely. "I'd love to send [Baltimore Gas & Electric Co.] a note saying, 'We don't need your power anymore,'" he said.
—Kurt Kleiner, “For This Student, Generating Solar Power Begins at Home,” Baltimore Business Journal, May 27, 1991
The grid in this phrase is the informal name given to the electricity network's interlocking system of transmission lines and power stations. So, not surprisingly, off the grid originally meant only a disconnection from the electricity supply, and has been used in that sense in the power industry for some time.