The 5-megawatt Pitkin Solar Project near Woody Creek, completed in 2021, is one of Holy Cross Energy’s renewable energy sources. This view was provided during an EcoFlight day trip.
Glenwood Springs-based Holy Cross Energy announced last week that it is on track to achieve a 90% renewable energy portfolio by the end of 2025, bringing the cooperative closer to its goal of distributing 100% renewable power by 2030.
The cooperative said in a news release that two solar and storage facilities under construction in Garfield County and recent agreements with existing wind and solar facilities on Colorado’s eastern plains will make its jump in renewables possible. Holy Cross announced that its power supply was 76% renewable in March of this year.
Holy Cross serves roughly 45,000 customers throughout the Roaring Fork, Colorado River and Eagle River valleys. The entire towns of Snowmass Village and Basalt, as well as large portions of Aspen and Carbondale, fall within Holy Cross’s service area. Founded in 1939, Holy Cross is a not-for-profit rural electric cooperative, meaning it is owned by its customers.
The announcement signifies that Aspen-area power users will rely almost entirely on renewable power after 2025. The city of Aspen’s city-owned utility, which covers the city’s downtown core, achieved a 100% renewable energy supply in 2015. Holy Cross covers power users in the rest of the Aspen area, including users in the Aspen Airport Business Center, Mountain Valley, Hunter Creek, Red Mountain, Cemetery Lane and the base of Highlands.
Holy Cross has drastically increased the portion of renewable sources in its energy portfolio during the last seven years, Holy Cross’s power supply was 39% renewable in 2017.
The cooperative is pursuing a “100x30” goal, under which it aims to have an entirely renewable energy portfolio by 2030.
CEO Bryan Hannegan said in an interview that Holy Cross has replaced wholesale power contracts for energy from the regional grid, which often comes from fossil fuel-based sources, with renewable power projects built specifically for Holy Cross and its members. Hannegan said federal renewable energy tax credits, updates in regional power transmission infrastructure and technological advancements have all made renewable power more affordable and more accessible for Holy Cross in recent years.
“We saw the business opportunity — the opportunity to keep rates low for our members,” Hannegan said.
The news release states that the cooperative’s customers will see about $40 million in savings over the next 10 years as a result of the four new power projects in Garfield County and on the eastern plains. The savings are in comparison to Holy Cross’s existing power supply portfolio.
Nonetheless, Hannegan said that making the last 10% of its power supply renewable will be uniquely challenging. He expects Holy Cross will need all five years after 2025 to reach its 100% renewable goal.
Hannegan said Holy Cross still relies on power wholesalers, which are not entirely renewable, to fill in gaps when the cooperative doesn’t have enough supply from its own sources.
“There are times when … we're in an oversupply situation in some hours of the day, and in that same day, later on, we might have not enough under contract, so we need to rely on the wholesale power market and our wholesale partners to fill in the gap,” Hannegan said.
Finding reliable renewable sources to fill that gap will be a different challenge from simply replacing the bulk of Holy Cross’s energy sources with renewables, Hannegan said. He said Holy Cross will need to seek out renewable options other than solar and wind to act as backup supplies when the sun isn’t shining and the wind isn’t blowing. He mentioned pumped storage hydropower and geothermal energy as possibilities.
Hannegan said Holy Cross members have not been interested in seeking nuclear power sources. He said nuclear power would likely need to become more affordable and solutions for nuclear waste disposal more realistic before members consider exploring that option.
Boosting renewable supply
Two upcoming Garfield County solar and storage facilities — the High Mesa and Mamm Creek projects — will be key in boosting Holy Cross’s renewable sources to 90% of its portfolio, according to the cooperative.
The High Mesa project is a 10-megawatt solar array and 20-megawatt-hour storage facility currently under construction near Parachute, expected to come online this summer. The Mamm Creek project, which has the same solar power generation and storage capacity, is under construction near Rifle and is expected to come online in early 2025. Both projects are being built by the Virginia-based energy company AES Corporation.
Hannegan said the massive lithium-ion batteries at High Mesa and Mamm Creek will allow Holy Cross to save up power generated during the day and distribute it during high-demand periods at night.
On top of these facilities, Holy Cross expects upgrades in Minneapolis-based power distributor Xcel Energy’s Colorado transmission infrastructure to increase the power it receives from the Bronco Plains II wind farm in Kit Carson County, near the town of Flagler. Holy Cross currently has a contract to receive 150 of the Bronco Plains II facility’s 200 MW capacity in the winter and 100 MW in the summer. Bronco Plains II began producing power in December. Florida-based NextEra Energy Resources built, operates, and owns the project.
In addition, Holy Cross purchased rights to 30 MW from the 75 MW Hunter Solar project in Arapahoe County, also in December.
Holy Cross recently lost one of its renewable energy producers when Gypsum’s Eagle Valley Clean Energy Biomass Plant, owned by Greenbacker Capital, announced on April 17 that it would file for bankruptcy and cease operations. The plant accounted for 7% of Holy Cross’s power supply, though the cooperative has said it was the most expensive renewable power in their portfolio.
Holy Cross added a renewable power source in the Roaring Fork Valley in 2021 when it began receiving power from the 5 MW Pitkin Solar Project near Woody Creek. The project was built by California-based Primergy Solar.