SunZia: US's Largest Renewable Project Now Operational

Pattern Energy has announced that SunZia is now fully operational. According to Pattern Energy, the facility is the largest renewable energy infrastructure project in US history.

The installation consists of a wind farm with approximately 3.65 GW capacity and a 550-mile high voltage direct current (HVDC) transmission line. Together, these components could deliver more electricity than the Hoover Dam, which for decades was the country's largest clean energy facility.

According to Pattern Energy, SunZia could supply electricity to around one million American homes annually when running at full capacity. Construction work started in September 2023, though planning for the project began much earlier.

The wind farm spans sites across New Mexico, whilst the transmission line connects generation facilities to demand centres in Arizona and beyond.

"SunZia becoming fully operational is a milestone more than 18 years in the making and one that I've been fighting for since I first came to Congress," says Martin Heinrich, US Senator for New Mexico.

"Through a whole series of obstacles spanning over a decade and a half, we kept working to move it forward because we knew what it could mean for America's energy future and New Mexico's role in leading it."

Transmission capacity and HVDC technology

The transmission line forms a key part of the project. The high voltage direct current system can move large volumes of electricity efficiently over long distances using converter stations positioned at each end.

According to Pattern Energy, the line is one of the first major HVDC systems built in the US in decades. The technology addresses constraints that have limited interregional power distribution.

"Large-scale transmission is essential to meeting the West's growing energy needs and strengthening reliability across the grid," says Elliot Mainzer, President and CEO of the California Independent System Operator. "Projects of this scale help deliver energy reliably to areas of rising demand, improve the movement of power across states and support a more resilient, flexible and affordable electric system."

Elliot adds that SunZia represents the kind of infrastructure investment needed to serve customers and prepare the grid for future requirements. The project demonstrates how transmission infrastructure can unlock renewable generation capacity that would otherwise remain stranded from major population centres.

Hunter Armistead, CEO of Pattern Energy, describes the project as proof that large infrastructure remains achievable in the US.

"We did this the right way, we did it on time and on budget – in genuine partnership with the local communities and landowners who trusted us, with the environmental stewardship this unique landscape deserves, and with the determination to see something through that many thought was too big and too complex to finish," says Hunter.

Capital investment and employment

According to Pattern Energy, the project represents more than US$20bn in investment across New Mexico and Arizona communities. The figure includes US$1.3bn in direct payments to local governments, schools, counties and private landowners over the first 30 years of operation.

The construction phase supported more than 2,000 jobs at peak activity. According to Pattern Energy, the facility will sustain more than 100 operations roles on a permanent basis.

"SunZia is supporting local jobs, strengthening the local tax base and creating long-term investment that can help support schools, public services, landowners and families across the region," says Barbara Sultemeier, Board Member for the Corona Landowner's Association through the Lincoln County Community Foundation.

Vestas, which supplied turbines and components for the project, employed workers from the surrounding region.

"For Vestas, this is our largest onshore wind project in North America but the number that stays with me isn't just the gigawatts. It's the people," says Laura Beane, President for Vestas North America.

Laura notes that nearly 90% of the workforce hired for the project came from New Mexico. She adds that Vestas factories in Colorado expanded from a few hundred employees to more than 1,000 to meet delivery requirements.

Political context and policy environment

SunZia begins operation during a period when the US Government has introduced measures to limit domestic wind projects. Since President Donald Trump began his second term in January 2025, he has described wind energy as the "scam of the century".

According to reports, Trump has issued executive orders to prevent new wind projects. The administration has also offered payments to operators to stop construction of wind farms.

The opening of SunZia could provide a reference point for future transmission projects. However, the 18-year timeline from planning to operation illustrates the obstacles facing interregional transmission lines in the US.

Pattern Energy now operates more than 40 facilities across North America with nearly 12,000 MW of operating and in-construction capacity. According to Hunter, the company plans to continue expanding its portfolio.

"This project sets a new standard for what is possible – and we intend to keep building on it," says Hunter. For sectors dealing with data centre demand and ageing grid infrastructure, SunZia offers a working model of large-scale transmission investment.