Dec. 4—Kern's ambitious list of carbon burial proposals has lengthened with the addition of an early-stage, relatively inexpensive plan for reusing an idle biomass plant near Delano to combust local ag waste then burying the byproduct gas while generating small amounts of electricity or hydrogen.
A company based in Rancho Cordova that uses rocket technology to increase burn efficiency has initiated preliminary talks with Kern County government as it pursues a similar biomass plant-reuse project in Mendota under a new partnership with Microsoft and oil industry giants Chevron and Schlumberger.
The projects are not without skeptics who question claims the process is carbon negative and doubt the technology itself. Environmental groups have been critical of carbon capture and sequestration generally; they're no more receptive to burning biomass and burying its byproduct carbon dioxide.
If Clean Energy Systems' project in Mendota lives up to its billing as a safe, financially viable, zero-emission solution for handling the Central Valley's massive production of ag waste, the company's proposal in northern Kern could join at least three other projects in the county that, though unrelated to biomass, all aim to address climate change by injecting CO2 deep underground.
CES has purchased the former 50-megawatt, 1,200-ton-per-day Covanta Delano LLP biomass plant that was shut down in 2015. That was after a large share of the state's biomass power plants shut down several years ago in the face of competition from against other renewable energy producers.
The loss of facilities that had taken in ag waste resulted in a glut of feedstock, leading many farmers to burn their woody waste openly. Regulations on such pollution have since tightened while mulching of shredded orchards and vineyards has become more common. Even so, some growers are finding customers for their biomass.
After CES initiated a conversation with officials in Kern, the county did a preliminary assessment that led it to inform the company in early 2020 it would have to perform a full environmental review and pay certain fees. Things have stopped there.
"We are not actively processing any permit for any Clean Energy Systems project anywhere in unincorporated Kern County," the county's top energy-permitting official, Lorelei Oviatt, said by email.
Environmental advocates who would prefer the project remain on hold have raised a number of concerns not unique to the CES proposal near Delano.
They question calculations suggesting biomass combustion combined with carbon sequestration is truly carbon negative. They note it takes a great deal of energy to capture, compress and inject carbon, not to mention the associated activities of gathering and transporting biomass.
Environmental groups point to the risks of transporting carbon dioxide by pipeline to an injection site, considering its dangers as an asphyxiant. Plus, they worry what might happen decades later after the company that buried it is no longer legally liable for its safe sequestration.
"Bringing the Delano facility back online presents real dangers to air quality, public health and our climate," Victoria Bogdan Tejeda, staff attorney for the Arizona-based Center for Biological Diversity, said by email.
"Instead of investing in more carbon burning and risky pipelines, the (Central Valley) needs clean energy solutions like distributed solar," she continued. "Communities in the San Joaquin Valley shouldn't be made a dumping ground for carbon waste."
Clean Energy Systems President and CEO Keith L. Pronske promised there will be no emissions at all in Delano but that it will sequester more than half a million tons per year of carbon dioxide while also producing hydrogen or electricity for the transportation sector on the order of 5 to 10 megawatts.
The operation will employ 35 to 50 people when it opens within five years, Pronske said. He added that the project's cost is in the hundreds of millions of dollars — well below the price tag of billions attached to other local carbon burial projects — and that the privately held company is talking to potential financial partners.
He acknowledged there's plenty of work to do in Delano but that the focus now must be on the Mendota project, which has applied for a federal carbon injection permit and last month hosted a public hearing.
"We shut down half the biomass plants in the state," he said, "so the plan is to get them back on but without the pollution."