Best: How can Holy Cross Energy possibly get to 92%? |

Best: How can Holy Cross Energy possibly get to 92%?

Allen Best
Big Pivots
Allen Best
Courtesy photo

Let’s start with the obvious. The sun doesn’t always shine and, except for springtime in Colorado, the wind doesn’t always blow.

So how can Holy Cross Energy possibly achieve 92% carbon-free electricity? The electrical cooperative serving the Vail, Aspen and Rifle areas expects to get there in 2024. Last year it moved past 50% emissions-free energy.

And if Holy Cross can do it, what is possible for electrical cooperatives serving Crested Butte and Steamboat Springs, Holyoke and Crestone? Or, for that matter, the investor-owned utilities that deliver electricity to Denver and Boulder, Sterling and Pueblo?

Directors of Holy Cross several years ago adopted what seemed like the audacious goal of achieving 100% emissions-free power by 2030. At least one other electrical utility in Colorado adopted a parallel goal but festooned it with conditions. Holy Cross’s pledge had no footnotes. 

I expected an incremental movement in the next few years. After all, both wind and solar have become incredibly cheap, the fuel itself essentially free, unlike coal and natural gas.

But can the lights be kept on all the time? Resource adequacy has become a major question in this energy transition. Coal plants, if sometimes down, are far more reliable than wind and sunshine. Now we’re hurriedly closing those high-priced and polluting plants. Natural gas can respond quickly to demand. However, those plants are costly and pollute, too.

Do we need more?

Colorado’s two largest electrical providers, Xcel Energy and Tri-State Generation and Transmission, both say they can achieve the state’s goals of 80% carbon reduction by 2030 as compared to 2005 levels. But both have refrained from embracing higher, short-term goals.

Tri-State, which delivers power to 17 of the state’s 22 electrical cooperatives, warns of ambitions over-stepping realities. At the wholesale provider’s annual meeting in Westminster this week, chief executive Duane Highley likened resource adequacy to a “big bad wolf.” The Western Energy Coordinating Council in December warned of risks to the grid in the Western U.S. by 2025 of insufficient resources to meet electric demand.

Storage will be crucial. Lithium-ion batteries, if increasingly more affordable, can store electricity for just a few hours. We need technologies that can store energy for days if not weeks. Xcel Energy will be testing one such long-term technology, called iron-air, at Pueblo. Colorado wants to be part of the elusive answer to hydrogen, perhaps using the existing electricity infrastructure at Craig. And transmission and other new infrastructure, such that could allow Colorado to exploit the winds of Kansas or the sunshine of Arizona, can help — but remains unbuilt.

Despite its high-end resort members, Holy Cross actually has the second lowest electrical rates among Colorado’s 22 electrical cooperatives. And its rates are 5% less than those of Xcel. This is not Gucci electricity, a Tesla Model X Plaid. The Aspen Skiing Co. and Vail Resorts make snow with some of Colorado’s lowest electricity rates.

Bryan Hannegan, the chief executive and head wizard at Holy Cross, laid out his utility’s broad strategy in recent presentations to both state legislators and the Avon Town Council. Holy Cross, he explained, will add new wind from eastern Colorado and several new solar-plus-storage projects within its service territory.

Holy Cross also intends to integrate new storage in homes and businesses. It incentivizes batteries at homes that can be tapped as needed to meet demand from neighborhoods. Holy Cross also wants to integrate vehicle batteries, such as from electric school buses, in its efforts to match demands with supplies. Another key component is time-of-use rates, a market mechanism that aims to shift demands to times when renewable electricity is most readily available — and cheapest.

Importantly, Holy Cross expects to achieve this high mark without the need of new natural gas capacity.

Much of the environmental community loathes the idea of new — and always expensive — natural gas plants that will rarely get used. Some utilities, however, see more gas as necessary to ensure power never gets disrupted.

Hannegan, speaking to the Avon council, said he was confident of resource adequacy to meet new demands for electric vehicles, heat pumps, and other electric uses. He called it “smart electrification.”

Holy Cross’s journey from 92% to 100%, though, will “be a bit of a doozie,” he said. He likened it to the climb from Camp 4 on Everest to the peak. 

“We have to think about how we balance (supply and demand) at every location on our grid at every moment of every day,” he said. That “fine-grained balancing” will be “quite an engineering challenge. There is reason we have given ourselves six years” to figure this out.

What is to prevent the work Holy Cross is doing from being replicated elsewhere? I’ll address that and other questions on another day.

Allen Best publishes Big Pivots, which focuses on climate change and the energy and water transitions in Colorado. See more at