Nevada Can Exit Coal and Maintain Electric Reliability

A new analysis shows that Nevada can complete its transition away from coal-fired electricity—closing the Valmy and TS Power plants—while keeping the electric system reliable, at reasonable cost to the bulk power system.

Nevada began its move away from coal in current-Governor Brian Sandoval’s first term by passing Senate Bill 123, which required Nevada’s investor-owned electric utility, NV Energy, to eliminate 800 megawatts of coal-fired power plants from its portfolio and replace these plants with a mix of cleaner-than-coal natural gas and renewable generation. These 800 megawatts comprised the Reid Gardner Generating Station and NV Energy’s portion of the Navajo Generating Station. For context, an 800 megawatt power plant operating 80 percent of the time is sufficient to power around 520,000 households.

But, when lawmakers passed Senate Bill 123, they did not touch two northern Nevada coal facilities: the 522-megawatt North Valmy Generating Station, jointly owned by NV Energy and Idaho Power, and the 200-megawatt TS Power Plant, which is owned by Newmont Mining Corp and supplies electricity to its mines and NV Energy customers. A recent Idaho Power analysis of its power plant portfolio found that closing at least one the two units at North Valmy in 2019 would be cost-effective. The TS Power plant opened in 2008 and incorporates modern emission controls, but still emits a lot of carbon dioxide pollution.

To look at how the closure of TS and Valmy would change the performance of the transmission system in northern Nevada, Sierra Club and NRDC commissioned a consulting firm, Comprehensive Power Solutions to produce an independent analysis. They modeled the transmission system using industry-standard tools and assumptions, examining whether the removal of the power plants would create changes in power flows sufficient to violate reliability standards.

They found that relatively minor changes and targeted investments in northern Nevada’s transmission system could mitigate the most important transmission problems caused by a shutdown of the two plants. The authors found that making these changes and targeted investments would not be very expensive, on the order of $1.8 million to $5.5 million, in addition to the cost of replacing the electricity provided by the plants. For context, the TS Power Plant cost $630 million to build.

In all, the analysis shows that Nevada can complete its transition away from coal, while still maintaining a reliable electricity transmission system. Shutting down these plants would create opportunities for cleaner alternatives, reduce emissions and position the state even better for compliance with the U.S. Environmental Protection Agency’s Clean Power Plan, the nation’s first-ever limits on our largest source of carbon pollution, power plants.

When the new Nevada legislature gathers in 2017, it should consider passing legislation that requires the shut-down of these plants, and their replacement with clean energy sources like solar, wind, geothermal, and energy efficiency.