Such a short time ago, 80% emissions reduction seemed such a bold goal. A new report says far more is possible.

By Allen Best

It seems like many years ago since Ben Fowke, chief executive of Xcel Energy, standing on a podium at the Denver Museum of Nature and Science, announced that his company was confident it could decarbonize the electrical generation across its six-state operating area 80% by 2030 as compared to 2005 levels. This, he said, could be done using existing technology.

That declaration in December 2018 was national news. So was the company’s disclosure in December 2017 of the bids for renewables to replace the two coal-fired units it intended to retire at Pueblo, Colo. They came in shockingly low.

Now, 80% plans by 2030 are becoming almost commonplace. Consider the trajectory of Colorado Springs. The city council there, acting as a utility board, in June accepted the recommendation of city utility planners to shut down the city’s two coal plants, the first in 2023 and the second in 2030.

That was the easy decision. But the Colorado Springs City Council, in a 7-2 vote, also accepted the recommendation to bypass new natural gas capacity. Xcel is adding natural gas capacity to its portfolio in Colorado, although the plant already exists.

Colorado Springs is now on track to get to 80% reduction by 2030.

As a municipal utility, Colorado Springs was not required by Colorado to reduce its emissions 80% by 2030. That applies to those utilities regulated by the state, and municipalities are exempt. It is subject to broader economy wide goals of 50% by 2030 and 90% by 2050.

A city utility planner says he believes the city can achieve 90% reduction by 2050.

“I do believe personally that in the next 10 years we will see some major advancements in the technology that will allow those technologies to go down and be more competitive,” says Michael Avanzi, manager of energy planning and innovation at Colorado Springs Utilities.

A report issued by the Center for Environmental Public Policy at the University of California, Berkeley, says it shouldn’t take until 2050. Wind, solar, and battery storage can provide the bulk of the 90% clean electricity by 2035, according to the study, 2035 Report: Plummeting Solar, Wind, and Battery Costs Can Accelerate Our Clean Energy Future.

This, the study notes, can be done even while electricity costs decline. This finding contrasts sharply with studies completed more than 5 years ago, which found deep penetration of renewables would elevate costs. These lower costs are being reported across the country, the study found, even in those areas considered resource-poor for renewable energy generation. Colorado is the converse: It has excellent renewables, among the best mix in the nation.

The study is important and rich with detail. Among the seven members of a technical review committee was Steve Beuning, of Glenwood Springs-based Holy Cross Energy.

Hal Harvey

The findings, though, are best understood in terms of the policy assumptions, which are found in a separate study conducted by Energy Innovation, a San Francisco-based consultancy. Colorado gets several mentions, and it’s important to note that the chief executive is Hal Harvey, who grew up in Aspen. (Harvey has connections in high places; he inspired a column in late June by Thomas Friedman of the New York Times: “This Should Be Biden’s Bumper Sticker.”)

The conclusions describe an optimal set of policies to get the United States to 90% by 2035, including:

  • federal clean energy standards and, especially in the absence of that, extension of federal tax credits for wind and solar.
  • strengthening of federal authority to improve regional transmission planning by the Federal Energy Regulatory Authority.
  • reform wholesale markets to reward flexibility.

Researchers in California did not specifically examine the case of Colorado Springs but more broadly found that U.S. electrical utilities can tap existing gas-fired plants infrequently along with storage, hydropower, and nuclear power to meet demands even during times of extraordinarily low renewable energy generation or exceptionally high electricity demand. All told, natural gas can contribute 10% of electrical generation in 2035. That would be 70% less than the natural gas generation in 2019.

How did the California researchers decide how much natural gas would be needed to firm supplies? As the saying goes, the sun doesn’t always shine, the wind doesn’t always blow. And when would these times of low renewables intersect those of high demand? The researchers studied weather records for seven years, 60,000 hours altogether, and in 134 regional zones within the United States, from earlier in this century. That worst-case time, during the seven years examined, was on the evening of Aug. 1, 2007, a time when solar generation had declined to less than 10% of installed solar capacity, and wind generation was 18% below installed capacity

Based on this, they found a maximum need for 360 gigawatts of natural gas capacity. In other words, no new natural gas generation was needed. We have enough already.

Peak demand in Colorado Springs usually occurs late on hot summer afternoons. The all-time record demand of 965 megawatts occurred on July 19, 2019. As Colorado Springs grows during the next three decades, it will possibly become Colorado’s largest city, with demand projected to push 1,200 megawatts (1.2 gigawatts) at mid-century.

For Avanzi and other utility planners charged with creating portfolios for consideration by elected officials, closing coal plants was an easy case to make. Coal has become expensive, severely undercut by renewables.

Also considered were 100% emission-free portfolios by 2030, 2040, and 2050. But they were seen as too risky and too costly, at least at this time.

Portfolio 17, the one ultimately adopted by the city council on June 25, calls for the Martin Drake plant to be closed in 2023 and the Ray Nixon plant in 2030.

Seven portable gas generators are to be installed at the Drake plant for use from 2023 to 2030, a need dictated by the existing transmission and not the inadequacy of renewables. Colorado Springs already has a gas plant, but the city council members accepted the recommendation of utility planners that no new plant will be needed. That vote was 7-2.

A natural gas plant located northeast of Denver operated by Tri-State Generation and Transmission. Photo/Allen Best

Writing in PV Magazine, Jean Haggerty pointed out that Colorado Springs was part of a trend among utilities to avoid building new natural gas bridges to renewable energy. Tucson Electric Power also plans to skip the gas bridge. And, on the East Coast, Florida Power & Light and Jacksonville’s municipal utility reached agreement to rely on existing natural gas and new solar generation when they retire their jointly owned coal plant, the largest in the United States.

In creating the portfolios, Avanzi says he relied upon mostly publicly available reports, especially the National Renewable Energy Laboratory’s annual technology baseline and U.S. Energy Information Administration documents. For battery storage, he relied upon a study by energy consultant Lazard.

Colorado Springs’ plan calls for 400 megawatts of battery storage by 2030. Previously plans for a 25-megawatt battery of storage are expected to come on line in 2024.

All types of storage were examined. The single largest storage device in Colorado currently is near Georgetown, where water from two reservoirs can be released to generate up to 324 megawatts of electricity as needed to meet peak demands. The water then can be pumped uphill 2,500 feet to the reservoirs when electricity is readily available.

Colorado Springs studied that option. It has reservoirs in the mountains above the city. It found the regulatory landscape too risky.

The most proven, least risky, technology is lithium-ion batteries that have four-hour capacity and flow batteries with six hours capacity. They can meet the peak demand of those hot, windless summer evenings after the sun has started lessening in intensity.

This is from the July 8, 2020, issue of Big Pivots.  Sign up here to get free copies.

 

Allen Best
Follow Me