NREL: NREL Innovations Open Door to Industry Collaboration, Commercialization

What works for Erika Erickson is invisible to the naked eye, but the problem she is attempting to solve is certainly not invisible.

A postdoctoral researcher at the National Renewable Energy Laboratory (NREL), Erickson and her colleagues have turned to microscopic enzymes to literally eat away at the growing problem of plastic waste. They identified and characterized enzymes able to break down polyethylene terephthalate (PET), the lightweight plastic you might recognize as bottles and food packaging. That is merely the first step, along with two pending patent applications.

Erickson said the objective is to tailor enzymes that can target other types of products made from the same plastic material, such as clothing and carpet. “None of those things right now have a recycling option available,” she said. “So that’s the long-term goal for these enzymes.”

Filings in Foreign Lands Soared Above Prior Year
NREL researchers made for an inventive bunch in fiscal year 2021, even exceeding record-breaking activity in FY ‘20. A patent issued in November 2021 for compressed gas energy storage, for example, which covers the idea of injecting compressed natural gas into defunct oil and gas fracking sites, accounted for just one of 36 issued patents in FY ’21. A total of 40 patents were issued the previous year.

During the same period, patent applications filed in foreign jurisdictions increased to 50 from 34.

Anne Miller, technology transfer director at NREL, said the foreign applications lag the filings made to the U.S. Patent and Trademark Office. “It’s usually a pretty good sign if we’re filing outside of the U.S.,” she said. “That means we’re doing that because we have a licensee or a good prospect of one. This is part of the uptick in interest we’ve seen in licensing lab-developed technologies.”

Technology developed at NREL is available for licensing, and in many instances, companies partner with the laboratory to help move an idea closer to commercialization. The U.S. Department of Energy maintains a database of available patents at the Lab Partnering Service website.

Before an invention is patented—even before an application can be filed—researchers at NREL file with Miller’s office what is known as a record of invention, or ROI. Researchers collectively filed 161 ROIs during FY ‘21, a slight increase from the 153 a year earlier. During the same period, the number of new innovations registered rose to 283 from 265. New innovations also cover records of software developed at the laboratory; those numbers increased to 122 from 116 in FY ‘20.

Enzymes Reveal Taste for Degrading Plastic
The patents pending for polymer-degrading enzymes addresses the global problem of plastic waste. Filed on behalf of Erickson and Japheth Gado from NREL, John McGeehan from the University of Portsmouth, and Gregg Beckham—who leads the BOTTLE Consortium’s efforts to tackle the problem—the patents cover engineered enzymes and a microorganism able to digest PET.

“The enzymes are really particular about what they might be active on,” Erickson said. “In this case, we’re using enzymes that probably evolved to degrade natural polymers—perhaps the stuff that would keep an organism or a pathogen out of a plant, for example, or that make the structural bits of plants. Those look just similar enough to certain synthetic plastics that we have identified enzymes that do have activity for breaking down these synthetic polymers as well.”

Gado, a postdoctoral researcher at NREL, provided the starting point. He conducted a computational analysis of thousands of enzymes and winnowed the list down to 74 candidates with the potential to be active on PET. The research into the enzymes centers on how well they can break down the PET, and how rapidly.

“We’re really going for even the poor actors at this point to get a good foundation of options,” said Erickson, who joined NREL in 2019 after earning her doctorate in plant molecular biology from the University of California, Berkeley. “After we have a sense of who can do this job, then we compare the rates. In the initial screening, where we were just looking for candidates, we gave them a long time, like four days to see if they would do anything at all.”

The enzymes that can break down the PET in the shortest amount of time could be useful for an industrial application. “I see this as more of like the launching point,” said Erickson, whose work is funded by BOTTLE, which is supported by the Department of Energy’s Bioenergy Technologies Office (BETO) and Advanced Manufacturing Office. “There will be a lot of work that stems from these enzymes to improve them for the future.”

Sustainable Aviation Fuel Begins Under a Microscope
Erickson is not the only researcher at NREL thinking small.

Min Zhang, a senior scientist at NREL, has devoted considerable effort and attention to Zymomonas mobilis, a bacterium with a proven use in the field of biofuels. Her most recent patent—awarded with Yat-Chen Chou, Mary Ann Franden, and Michael Himmel—provides a pathway that can be used for sustainable aviation fuel. No quick discovery, Zhang has been working with the microorganism since joining NREL in 1992 and has accumulated a portfolio of patents related to Zymomonas. The researchers previously genetically modified the bacterium so that it yields ethanol after digesting five-carbon sugars derived from biomass. Natively, the microorganism is only able to ferment sucrose, fructose, and glucose.

The newly patented process pushes the microorganism in a slightly different direction. Further engineering has closed off the sugar-to-ethanol pathway. Instead, the modified Zymomonas produces 2,3-butanediol, a commodity chemical usually produced from oil. Biologically produced 2,3-butanediol lowers the greenhouse gas emissions substantially. The ability of the microorganism to accomplish this opens a pathway to the manufacture of other chemical products, which also can be further catalytically converted to sustainable biofuels. The researchers also engineered the bacterium to digest sugars with a more complicated chemical formula as a carbon source for its production. Those sugars come from agricultural waste, providing a renewable source.

More recently, Zhang said, a potential industry partner is interested in licensing the technology, using their industrial waste to produce 2,3-butanediol, which broadens the use of other feedstocks for the organism.

“It’s a perfect kind of collaboration that we can bring our technology into a commercial scale,” said Zhang, whose research is funded by BETO.

Patent Pending for Perovskite Production Process
Bryon Larson and Obadiah Reid are both looking toward the day when producing solar modules will be as simple as printing a newspaper. The realization of that idea relies on liquid-based solar materials such as organic semiconductors or perovskites, which can be inked onto a roll-to-roll press and produced quicker and cheaper than what it takes to manufacture the commonly used silicon solar panels. The speed means careful attention must be paid to ensure photovoltaic film quality in real time, and the two researchers have discovered a way to automate the process.

The two, who are part of NREL’s Chemistry & Nanoscience Center, have a patent application pending for their device that measures the quality of a perovskite film as it is being made. Perovskites are an exciting class of solar materials that still efficiently convert light to electricity even with some defects, but too many or especially the wrong kind of defects will cause a drop in efficiency and shorten the operating lifespan of the technology.

“We want to be able to ensure that perovskite manufacturers are not only getting a quality perovskite off a production line, but one that’ll retain that quality well after it’s put to use,” Larson said.

Their device is a black box the size of a large briefcase that uses microwaves and a light source to continuously monitor the film passing beneath and flag any potential defects or deviations from an optimal manufacturing process.

“When you’re running one of these roll-to-roll coating lines, it’s very expensive,” Reid said, “so the earlier you can identify something going wrong and correct it, the better. The hope here is that you can give them real-time feedback.”

The Department of Energy, which owns NREL, already flagged the technology as incipient intellectual property worthy of broad attention. An Oregon company, Tau Science Corporation, received federal Small Business Innovation Research funding to work with NREL on the device.

Reid and Larson said the process involved in filing a patent application on the device has been a smooth one, thanks to guidance and support from NREL’s Technology Transfer Office.

“I have really enjoyed involvement with the tech transfer office here learning about IP, learning about how all this works, getting the bigger picture by seeing a discovery lead to market impact—it helps a lot to see beyond my little tunnel vision in the lab when it comes to real work impact,” Larson said.