NV Energy will keep looking for resources to replace its coal-fired North Valmy Generating Station, scheduled for retirement in 2025, after Nevada regulators shot down the utility’s plan for a $466 million battery storage system.
The Public Utilities Commission of Nevada (PUCN) voted 3-0 last week to reject the project. The battery storage system was part of NV Energy’s fourth amendment to its 2021 integrated resource plan (IRP). The commission approved the amendment in part, but denied some components.
NV Energy had planned to replace capacity lost from the North Valmy coal plant closure with the Hot Pot and Iron Point solar-plus-storage projects. The 522-MW North Valmy plant, in Northern Nevada, is NV Energy’s only remaining coal-fired power plant.
Hot Pot and Iron Point together would provide 600 MW of solar paired with 480 MW of battery storage. In January 2022, PUCN approved NV Energy’s plan to buy Hot Pot and Iron Point from developer Primergy Solar.
But in its proposed IRP amendment, NV Energy said that due to supply-chain issues, Hot Pot and Iron Point are “no longer expected to move forward as previously approved.”
The 200 MW Valmy battery system was intended as a substitute for Iron Point and Hot Pot. NV Energy acknowledged the four-hour battery system wouldn’t be a total answer to the North Valmy coal plant closure, but said more resources could become available in Northern Nevada in the future.
But the commission wasn’t ready to give up on Hot Pot and Iron Point, saying NV Energy had “provided limited evidence” about the projects’ status.
“The commission finds it premature and unreasonable to approve the $466 million Valmy BESS investment as a cost-effective replacement for the Valmy coal plant without all the necessary facts,” the order stated.
The commission directed NV Energy to come up with a “complete solution” for the Valmy retirement in the next amendment to the 2021 IRP, or in its 2024 IRP, whichever comes first. The utility said it would file a fifth IRP amendment over the summer.
PUCN also asked for a thorough analysis of financial impacts of each potential solution for the Valmy closure.
And the commission wants details on “federal and state limitations on continued operations of the Valmy coal plant and associated costs.”
Another issue, the commission said, is whether NV Energy or its customers are entitled to damages resulting from delays in the Hot Pot and Iron Point projects.
In another part of the fourth amendment to its 2021 IRP, NV Energy proposed a 400-MW gas-fired peaker plant in Southern Nevada, which PUCN approved in March. (See Nev. Regulators OK Controversial Gas-fired Peaker.)
NV Energy also asked to postpone retirements of several gas-fired plants by five or 10 years. The commission approved the extensions and, in some cases, postponed the retirements even further. That includes the Silverhawk and Higgins generating stations, for which NV Energy had proposed a 2044 retirement date. Instead, PUCN set a 2049 retirement date, in recognition of the state’s 2050 target for economywide net-zero greenhouse gas emissions.
“At a time when planning to meet the energy needs of customers is more complex, the commission believes that all cost-effective options which also allow NV Energy to meet state environmental requirements should be modeled and considered,” the commission’s order said.
The commission also approved NV Energy’s addition of a 120 MW portfolio of geothermal resources.
NV Energy said the IRP amendment was intended to reduce Nevada’s dependence on the open energy market, improve reliability and advance the state’s clean energy goals.