Approximately three years after construction began, the largest wind facility in the United States, the SunZia Wind Project, is scheduled to begin commercial operations this month, June. The wind facility, located in New Mexico, has a total net summer generating capacity of 3,650 megawatts, comprising 916 wind turbines, and a total cost of $11 billion. SunZia’s capacity is more than three times that of the next two largest wind facilities, Alta Wind in Southern California (1,098 megawatts) and Great Plains in northern Texas (1,027 megawatts). Some of the turbines began producing power in April, during a testing phase. The wind facility spans three counties and took almost two decades of permitting and planning. The northern part of SunZia, located in San Miguel and Lincoln counties, has 242 turbines, while the southern part in Lincoln and Torrance counties has 674 turbines. The wind facility is expected to export power to Southern California and Arizona.
Pattern Energy, the wind developer, also owns the SunZia Transmission Project—a 550-mile high-voltage direct current transmission line that goes from the SunZia Wind Project site in central New Mexico to south-central Arizona and is backed by the Canada Pension Plan Investment Board. SunZia Transmission line is rated at ±525 kilovolts and carries up to 3,000 megawatts of power — the largest voltage source converter installation in the United States, and one of the largest worldwide. By converting the wind power’s output from AC to DC at a converter station in Corona, New Mexico, and transmitting it as direct current across the corridor, the system dramatically reduces line losses. At the receiving end, a converter station inverts the power back to AC.
Of the SunZia transmission line’s 3,021 megawatt of power capacity, 2,131 megawatts will be delivered to Southern California via the Palo Verde Substation. On May 15, 2026, California’s grid operator recorded 7,122 megawatts of hourly wind generation, a figure 20% above the prior annual record, with SunZia’s turbines contributing during a pre-commercial testing phase. It is important to note that these massive transmission projects are needed to support wind and solar power, which must be sited far from demand centers since they need to be located where wind power is strong, and the sun is shining.
According to the Energy Information Administration, the Energy Department’s statistical arm, once SunZia comes online, wind power will account for 45% of the state’s energy capacity, followed by 19% each from solar and natural gas. These statistics are in terms of capacity, not generation, because wind and solar can produce only a fraction of the power that gas, coal, and nuclear can at the same capacity level due to their inefficiencies. While dispatchable plants can generate power at any time, non-dispatchable sources such as wind depend on the weather and need massive amounts of land. One advanced nuclear plant, for example, produces 33.17 megawatts per acre, while one offshore wind facility produces approximately 0.006 megawatts per acre, which is approximately 5,500 times less efficient than one nuclear plant, according to the Interior Department.
That is one reason why, in July 2025, President Trump signed an executive order directing the administration to end federal subsidies for wind and solar energy facilities. It is also because these renewable energy sources make the United States dependent on foreign-controlled supply chains that threaten national security. Wind and solar power require critical minerals that, in many cases, result in reliance on supply chains from China. Lithium, graphite, cobalt, and manganese are critical to the storage batteries used in wind and solar projects, and the rare-earth elements that China processes are needed for the development of wind turbines.
Before SunZia came online, New Mexico had approximately 3,997 megawatts of installed wind capacity. With SunZia, the state’s total wind capacity is about 7,647 megawatts.
The Permitting Took Almost Two Decades
According to Tech Times, Pattern Energy and its predecessors spent from 2006 to 2023 moving SunZia through federal environmental reviews, state regulatory approvals, route adjustments, and competing legal challenges before construction could begin. The project required Bureau of Land Management right-of-way approvals across federal land in two states, Arizona Corporation Commission certification for the transmission corridor, and coordination with multiple federal agencies, including the U.S. Fish and Wildlife Service.
Tech Times reports that in May 2025, the Ninth Circuit Court of Appeals reinstated a lawsuit filed by the Tohono O’odham Nation and the San Carlos Apache Tribe, which alleged that the Bureau of Land Management failed to properly consult the tribes before authorizing construction through a 50-mile segment of the San Pedro River Valley in Arizona. The district court that originally dismissed the case did so on statute-of-limitations grounds; the appeals court found those grounds incorrect and sent the case back for consideration on the merits. While construction on the entire line is now complete, the legal outcome could require post-construction mitigation, rerouting of future work, or formal remediation of culturally significant sites.
Conclusion
The U.S.’s largest onshore wind facility is about to begin commercial operation. Built in three counties in New Mexico, it will provide power to the state of Arizona and southern California. It consists of 916 turbines, has a capacity of 3,650 megawatts, and was built at a cost of $11 billion. Along with the wind facility, Pattern Energy, the wind developer, also owns the SunZia Transmission Project—a 550-mile high-voltage direct current transmission line that goes from the SunZia Wind Project site in central New Mexico to south-central Arizona. Of the SunZia transmission line’s 3,021 megawatt of power capacity, 2,131 megawatts will be delivered to Southern California via the Palo Verde Substation.
Wind power requires massive land use, is inefficient due to generating power at only a faction of the generation that an equivalent gas, coal or nuclear unit with the same capacity can generate, requires rare-earth minerals that China provides and is currently subsidized by the U.S. taxpayer that the One Big Beautiful Bill signed in July 2025 will eventually correct as wind is no longer a “new” technology and should stand on its own.
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