Coyote Gulch’s new bicycle arrives home November 2, 2019.
Coyote Gulch’s Leaf charging at the City of Thornton’s Infrastructure Maintenance Center August 31, 2019. Charging infrastructure partially paid for with a grant from the Colorado Energy Office.
The San Juan Generating Station in mid-June of this year. The two middle units (#2 and #3) were shut down in 2017 to help the plant comply with air pollution limits. Unit #1 shut down today and #4 will shut down on Sept. 30 of this year. Jonathan P. Thompson photo.
By now I suspect most of you are aware of the bad news of the day when it comes to the federal government’s power to limit carbon dioxide emissions from power plants. That power has been taken away by the conservative majority of the Supreme Court, which is on a rampage lately.
The case, West Virginia v. EPA, concerned the Obama administration’s Clean Power Plan, which limited carbon dioxide emissions from power plants in a manner that aimed at phasing out coal-fired power plants altogether — albeit not immediately and, some might say, not quickly enough. The Court ruled, 6-3, that only Congress can limit carbon dioxide emissions to a level that forces a nationwide transition away from coal, which is to say: Given that most of Congress is owned by corporations and so will do nothing, this ruling essentially gives corporations free rein to spew climate changing pollutants into the atmosphere. “The Court appoints itself — instead of Congress or the expert agency — the decisionmaker on climate policy,” noted Justice Elena Kagan in her dissent. “I cannot think of many things more frightening.”
Yeah, same here. I haven’t delved too deeply into the decision and all of its intricacies yet. But, from what I can tell, we aren’t doomed entirely by this decision, alone. That’s because it leaves a lot of tools intact that can be used to limit other pollutants, aside from carbon dioxide, from coal power plant stacks. And because in most places coal is being phased out anyway, thanks to economics, to years of tenacious environmentalists’ efforts, to state-level regulations, and, in some cases, thanks to corporate shareholders actually pushing companies to clean up their act.
This is where we get to today’s good news. Today (June 30) Public Service Company of New Mexico shut down one of two remaining units on the coal-burning San Juan Generating Station in northwestern New Mexico. In three months, PNM will abandon the entire plant and, if all goes according to plan, it will be demolished, the accompanying mine will shut down and be reclaimed, and a major solar array will be constructed nearby to utilize the capacity on the high-voltage transmission lines that spoke out across the West from the Shiprock Substation.
The smokestacks will cease emitting thousands of pounds of sulfur dioxide, mercury, arsenic, nitrogen oxides, and other harmful pollutants along with millions of tons of climate-warming carbon dioxide each year. The plant will stop gulping up more than 5 billion gallons of San Juan River water annually, leaving that water for other uses or to stay in the river for the fishes’ sake. And it will no longer dump millions of tons of toxic coal combustion waste in the mine and in settling ponds nearby. (The Four Corners Power Plant, a dozen miles away, will continue to burn coal and emit pollution).
And, to help offset the economic pain from losing one of the region’s biggest employers and tax payers, PNM will pay the affected communities tens of millions of dollars to develop their economies and help and retrain workers.
Yes, there is a hitch or two standing in the way of cleaner air and a diversified economy.
For starters, an obscure company called Enchant Energy has teamed up with the City of Farmington in a long-shot bid to take over ownership of the plant and keep it running as is until it can scrape up $1.4 billion or more to install carbon capture equipment on the plant. It’s a long-shot for a number of reasons, most of which are outlined in a story I wrote for the Energy News Network. But to sum up the obstacles:
Enchant has not lined up investors or financing for the project, in part because the only thing making the project remotely economically feasible are federal tax credits for capturing carbon;
Enchant has not secured water rights, transmission capacity, a coal contract, or any of the permits it would need to continue running the plant, let alone construct carbon capture and sequestration infrastructure;
PNM doesn’t want to buy electricity from the plant, and even if it did, New Mexico’s Energy Transition Act wouldn’t allow it to due to emissions limits;
New Mexico’s environment department is about to implement a rule that would prohibit the plant from running without carbon capture starting Jan. 1 of next year;
While Enchant might be able to sell power from the plant in the near-term, since many utilities are facing generation crunches this summer and next summer, it’s unlikely that many utilities are going to be willing to purchase dirty coal power in the future;
The idea of installing carbon capture on aging coal plants in order to keep them running is insane. If you’re really concerned about preserving jobs and tax revenues, why not invest that $1.4 billion (probably more like $1.7 billion, at least) directly into the affected communities? Why spend so much damned money just to keep polluting? And yes, even if the carbon capture equipment were ever installed, the plant would continue to spew out other pollutants at the current rate. Carbon capture may have a place on cement plants, for example, or even natural gas plants. Not on coal plants.
Most environmentalists I’ve spoken to are optimistic about Enchant, which is to say they are pretty confident that their attempt to keep the plant running after PNM leaves is not going to fly.
I hope they’re right. However, I can imagine a scenario in which Enchant and city leaders leverage the region’s deep ties to and reliance upon fossil fuels, along with the Biden administration’s apparent zeal for carbon capture, to lure federal subsidies to the project, maybe get some exemptions from state or federal agencies, and so forth, if only to keep dragging this scheme out for years. Maybe they’ll even switch gears and team up with the governor to create some sort of blue hydrogen production plant.
But I’m not going to let those unlikely scenarios get me down. I’m going to celebrate. I’ll wait a few days for the air to clear, then I’ll go up to a favorite high spot of mine atop the McElmo Dome and look out onto the landscape. And so long as there’s no wildfire smoke blowing through, I should be able to see it more clearly than I ever have before. And it should only get better.
Banner image: Wil Srubar holds a sample cube of concrete that contains biogenic limestone produced by calcifying macro- and microalgae. (Credit: Glenn Asakawa/CU Boulder)
Global cement production accounts for 7% of annual greenhouse gas emissions in large part through the burning of quarried limestone. Now, a CU Boulder-led research team has figured out a way to make cement production carbon neutral—and even carbon negative—by pulling carbon dioxide out of the air with the help of microalgae.
The CU Boulder engineers and their colleagues at the Algal Resources Collection at the University of North Carolina Wilmington (UNCW) and the National Renewable Energy Laboratory (NREL) have been rewarded for their innovative work with a $3.2 million grant from the U.S. Department of Energy’s (DOE) Advanced Research Projects Agency–Energy (ARPA-E). The research team was recently selected by the HESTIA program (Harnessing Emissions into Structures Taking Inputs from the Atmosphere) to develop and scale up the manufacture of biogenic limestone-based portland cement and help build a zero-carbon future.
“This is a really exciting moment for our team,” said Wil Srubar, lead principal investigator on the project and associate professor in Civil, Environmental and Architectural Engineering and CU Boulder’s Materials Science and Engineering Program. “For the industry, now is the time to solve this very wicked problem. We believe that we have one of the best solutions, if not the best solution, for the cement and concrete industry to address its carbon problem.”
Concrete is one of the most ubiquitous materials on the planet, a staple of construction around the world. It starts as a mixture of water and portland cement, which forms a paste to which materials such as sand, gravel or crushed stone are added. The paste binds the aggregates together, and the mixture hardens into concrete.
To make portland cement, the most common type of cement, limestone is extracted from large quarries and burned at high temperatures, releasing large amounts of carbon dioxide. The research team found that replacing quarried limestone with biologically grown limestone, a natural process that some species of calcareous microalgae complete through photosynthesis (just like growing coral reefs), creates a net carbon neutral way to make portland cement. In short, the carbon dioxide released into the atmosphere equals what the microalgae already captured.
Ground limestone is also often used as a filler material in portland cement, typically replacing 15% of the mixture. By using biogenic limestone instead of quarried limestone as the filler, portland cement could become not only net neutral but also carbon negative by pulling carbon dioxide out of the atmosphere and storing it permanently in concrete.
If all cement-based construction around the world was replaced with biogenic limestone cement, each year, a whopping 2 gigatons of carbon dioxide would no longer be pumped into the atmosphere and more than 250 million additional tons of carbon dioxide would be pulled out of the atmosphere and stored in these materials.
This could theoretically happen overnight, as biogenic limestone can “plug and play” with modern cement production processes, said Srubar.
“We see a world in which using concrete as we know it is a mechanism to heal the planet,” said Srubar. “We have the tools and the technology to do this today.”
A scanning electron micrograph of a single coccolithophore cell, Emiliania huxleyi. (Credit: Wikimedia Commons / Alison R. Taylor, University of North Carolina Wilmington Microscopy Facility)
Limestone in real time
Srubar, who leads the Living Materials Laboratory at CU Boulder, received a National Science Foundation CAREER award in 2020 to explore how to grow limestone particles using microalgae to produce concrete with positive environmental benefits. The idea came to him while snorkeling on his honeymoon in Thailand in 2017.
He saw firsthand in coral reefs how nature grows its own durable, long-lasting structures from calcium carbonate, a main component of limestone. “If nature can grow limestone, why can’t we?” he thought.
“There was a lot of clarity in what I had to pursue at that moment. And everything I’ve done since then has really been building up to this,” said Srubar. He and his team began to cultivate coccolithophores, cloudy white microalgae that sequester and store carbon dioxide in mineral form through photosynthesis. The only difference between limestone and what these organisms create in real time is a few million years.
With only sunlight, seawater and dissolved carbon dioxide, these tiny organisms produce the largest amounts of new calcium carbonate on the planet and at a faster pace than coral reefs. Coccolithophore blooms in the world’s oceans are so big, they can be seen from space.
“On the surface, they create these very intricate, beautiful calcium carbonate shells. It’s basically an armor of limestone that surrounds the cells,” said Srubar.
The coccolithophore has been part of the Black Sea ecology for millennia, and in the summer these calcite-shedding phytoplankton can color much of the Black Sea cyan. (Credit: NASA Goddard Space Flight Center, Flickr)
Commercializing coccolithophores
These microalgae are hardy little creatures, living in both warm and cold, salt and fresh waters around the world, making them great candidates for cultivation almost anywhere—in cities, on land, or at sea. According to the team’s estimates, only 1 to 2 million acres of open ponds would be required to produce all of the cement that the U.S. needs—0.5% of all land area in the U.S. and only 1% of the land used to grow corn.
And limestone isn’t the only product microalgae can create: microalgae’s lipids, proteins, sugars and carbohydrates can be used to produce biofuels, food and cosmetics, meaning these microalgae could also be a source of other, more expensive co-products—helping to offset the costs of limestone production.
To create these co-products from algal biomass and to scale up limestone production as quickly as possible, the Algal Resources Collection at UNCW is assisting with strain selection and growth optimization of the microalgae. NREL is providing state-of-the art molecular and analytical tools for conducting biochemical conversion of algal biomass to biofuels and bio-based products.
There are companies interested in buying these materials, and the limestone is already available in limited quantities.
Minus Materials, Inc., a CU startup founded in 2021 and the team’s commercialization partner, is propelling the team’s research into the commercial space with financial support from investors and corporate partnerships, according to Srubar, a co-founder and acting CEO. Minus Materials previously won the university-wide Lab Venture Challenge pitch competition and secured $125,000 in seed funding for the enterprise.
The current pace of global construction is staggering, on track to build a new New York City every month for the next 40 years. To Srubar, this global growth is not just an opportunity to convert buildings into carbon sinks but to clean up the construction industry. He hopes that replacing quarried limestone with a homegrown version can also improve air quality, reduce environmental damage and increase equitable access to building materials around the world.
“We make more concrete than any other material on the planet, and that means it touches everybody’s life,” said Srubar. “It’s really important for us to remember that this material must be affordable and easy to produce, and the benefits must be shared on a global scale.”
Students working in the Living Materials Laboratory, which utilizes calcifying microalgae to produce limestone and create a carbon neutral cement, as well as cement products which can slowly pull carbon dioxide out of the atmosphere and store it. (Credit: Glenn Asakawa/CU Boulder)
Students working in the Living Materials Laboratory, which utilizes calcifying microalgae to produce limestone and create a carbon neutral cement, as well as cement products which can slowly pull carbon dioxide out of the atmosphere and store it. (Credit: Glenn Asakawa/CU Boulder)
Click the link to read the briefing on the Alamosa Citizen website (Chris Lopez). Here’s an excerpt:
Those June rains
June 2022 was a good month for precipitation, measuring 1.27 inches and finishing above the .043 inches that is normal for the month of June in Alamosa, according to the National Weather Service Pueblo station.
For the past two years, 2021 and 2022, the month of June has measured above the historical norm, reversing a June pattern in 2020 and 2019 that fell below the norms.
When the winter months don’t yield the snowpack and spring runoffs needed to feed the Upper Rio Grande Basin, then it becomes essential that the summer rains show up to deliver some relief. So far, so good in 2022.
July 2021 was also good, bringing 1.14 inches of rain. Here’s to at least 1.04 inches of rain in July 2022 which would be considered a normal July year.
