Escalante Solar

The old coal plant looks like it’s getting swallowed by the new solar array. Escalante Solar was built across 1,714 acres on the site of the former 253 MW coal-fired Escalante Station in Prewitt, New Mexico, which was retired in 2020, as Tri-State Generation and Transmission Association pursues its Responsible Energy Plan.

The project brings 238 MWdc / 200 MWac of renewable solar generation to Tri-State’s members, including 11 electric cooperative members in New Mexico, under a power purchase agreement with Origis Energy.

“There’s some cool symbolism when you see it, especially from the air, of this coal plant that literally looks like it’s getting swallowed or enveloped by a PV array,” says Kevin Bassalleck, president of Albuquerque-based Gridworks, which provided construction services for the project.

Bassalleck says the symbolism of the project site “fits with not only the Energy Transition Act in New Mexico and the specific targets in that legislation, but just sort of broadly what’s happening in the industry with coal resources retiring and being replaced by solar. In this case, you can literally see it happening.”

He adds: “The backdrop is pretty dramatic when you see it out there with the desert mesas rising up right behind the array. The photos do a better job of saying that than I can put into words.”

Background

Gridworks became involved with the Escalante Solar project after having previously worked with the original developer of the project, Bassalleck says. The company also had a relationship with some of Tri-State’s distribution member co-ops.

“Some introductions were made between our team and Origis, and we worked pretty proactively with them from an early stage of the project,” Bassalleck adds. “There was a little bit of development engineering support, as it’s a pretty challenging site, and the site constraints are complex. The infrastructure around the coal plant is complex.”

Tri-State’s Responsible Energy Plan involves reaching 50% renewable generation by 2025, and the Escalante Solar project is a key component of reaching that goal, says John Hunter, project director at Gridworks. Tri-State’s 50% milestone is five years ahead of statewide sustainability targets.

Bassalleck explains that New Mexico passed the Energy Transition Act in 2019 to shift the state’s energy sources toward 100% renewables by 2050. The legislation sets a renewable energy standard of 50% by 2030 for investor-owned utilities and rural electric cooperatives and a goal of 80% by 2040. The law sets a zero-carbon resources deadline for investor-owned utilities by 2045 and rural electric cooperatives by 2050.

“At the time that was to some degree a controversial legislative package,” Bassalleck says. “I think a lot of the folks in the utility space probably thought those targets were far too aggressive and not feasible to hit.”

Bassalleck congratulated Tri-State for taking a progressive stance compared to other generation and transmission (G&T) companies in the state.

“Big kudos to Tri-State,” he says. “They took that seriously and really got after it from a procurement and resource planning perspective. And five years ahead of schedule is a big, big deal, especially for a G&T like Tri-State that geographically has a huge service territory.”

Challenges and innovations

Gridworks managed several challenges related to the project site, in terms of permitting, geology and archeological concerns. The company also faced a tight schedule to meet the interconnection date. Gridworks was able to overcome the obstacles through innovative coordination and communication between crews.

“Around the facility, there were a ton of easements that we had to work through with project constraints,” Hunter says. “We had easements that shifted midway through design just because of records dating back in the jurisdictions that weren’t that clear.”

In addition to the easements, the project site around the coal facility featured several different geologic conditions that required different approaches to install the solar array.

“The geological situation around the coal facility on the west side has actual rock that’s shallow, so we would have to drill in there,” Hunter says. “On the east side we had a harder clay that impacted drive times and driving abilities for pile installs. The northern side was very sandy.”

With a reservation located nearby, Gridworks also had to manage historical and archaeological areas around the site, Hunter adds. The company worked with Tri-State and Origis to ensure the proper measures were taken with those considerations.

“As we were working through the engineering issues with the schedule overall, the project from start to mechanical completion was eight months,” Hunter says. “The client had a very accelerated schedule due to interconnect, so we had to coordinate a lot of what we can do concurrently with grading all that stuff.”

At peak, Gridworks had about 440 personnel working on site. Between the challenges of the project site and the tight deadline to meet the interconnect date, Gridworks found innovative ways to coordinate its workforce.

“The biggest thing we did was just the coordination of the electrical effort with our civil, and then racking was falling right on top of it with pile install,” Hunter says. “We normally like to schedule about three weeks in between on projects of disciplines. Our disciplines were probably within a couple days of each other throughout the whole project. It was a massive coordination every morning figuring out where to move crews and how to keep crews going when we had hiccups.”

Planning for such hiccups was a key to project success.

“One of the big things we push here is ‘what if’ with Gridworks, and we always plan from A to Z,” Hunter says. “You have your Plan A, Plan B, but what if we fail? What pivot points do we have at these certain points? How do we manage it? Where do we turn? And that’s where we were really innovative, just the constant challenging our site teams to know, if something was to fail, what’s your next move?”

Local impacts

In addition to benefiting New Mexico as a whole, the Escalante Solar project had a big impact on the local community as well. The project will provide approximately $7.1 million in tax revenue for McKinley County and $2.4 million in taxes to the local school district over the life of the project.

The project has also provided jobs for the local community, between the construction and operations of the facility.

“We’re always excited about telling people we don’t want to just create jobs, we want to create careers for folks,” Bassalleck says. “We’ve got our own apprenticeship program, and we see a big uplift from that, not just in the local community, but then jobs that sort of permeate throughout the state on other projects down the road.”