Often the word “unique” is overused in today’s evolving society. However, that descriptor is completely appropriate to label the 231-mile (372-km)-long, single-circuit 500-kV One Nevada transmission line in the United States.

What other line caused construction workers to bundle up for an early fall mountain snowstorm at the exact time other workers on the same line had to stay hydrated because of temperatures that climbed to nearly 100°F (38°C)?

What other line is designed with a special tubular guyed-V structure to inhibit raptors from perching and attacking protected desert tortoises in southern Nevada or sage grouse in northern Nevada?

What other transmission line offers a critical solution to connecting two operating utilities for the first time and enabling Nevada customers to benefit from sharing generating resources?

And, what other line can simultaneously transport electrons from a large wind farm, numerous geothermal plants, large solar facilities and a small landfill energy resource?

The answer to these questions validates that the word “unique” does apply, indeed, to the One Nevada Transmission Line, or ON Line, which began serving homes and businesses in Nevada on New Year’s Day 2014.

NV Energy, 500-kV transmission line

Renewable Energy

The diversity of renewable energy in Nevada towers above most states, and ON Line plays a key role in enabling the energy to flow to customer load centers. Prior to the completion of this line, the energy from 20 separate geothermal projects could only be used in northern Nevada. Energy from eight of those geothermal projects is specifically contracted — through ON Line — to NV Energy’s operating company that serves the greater Las Vegas, Nevada, area. Energy from the rich solar resources in southern and central Nevada now can flow both directions on the line and find its way to where it is needed most.

One groundbreaking project that will use the new transmission line almost exclusively is the 110-MW Crescent Dunes Solar Energy Project, which is the largest solar power tower project with energy storage. Thanks to a molten salt storage system, this project can provide solar energy long after the sun has gone down and when air conditioners are still running full blast to counter midnight temperatures well above 90°F (35°C).

The new transmission line also is being used to move up to 152 MW of wind power from the Spring Valley Wind Project in eastern Nevada to Las Vegas, as well as a small landfill gas-to-energy project in northern Nevada. Overall, the initial phase of the line is designed to carry nearly 600 MW of renewable energy.