DOE Targets Biofuel for Hard-to-Electrify Transportation Modes - Part 2

As the Biden Administration has renewed a U.S. prioritization in reducing carbon dioxide emissions (CO2), advancing cleaner transportation alternatives to petroleum is increasingly prioritized too. Transportation is the world’s largest source of CO2 emissions.

While electrification is a cleaner alternative for some transportation modes, it’s not the answer for all of them. So, the Department of Energy (DOE) is focusing on alternatives – biofuels from municipal solid waste, crop residues, and other agricultural wastes. Its research shows potential to produce 8.3 and 10 billion gallons of biofuels, respectively (depending on the feedstocks).

BETO has invested nearly $124M recently (between two funding opportunities) to advance biofuels, believing this will help reach the federal government’s 2050 net zero emissions goal. This two-part series includes interviews with Valerie Reed, director of DOE’s Bioenergy Technologies Office (BETO) and Joshua Messner, a technology manager at BETO. They shed light on DOE’s work in this space, progress to date, and work to be done.

Waste360: Brief us on DOE’s history in converting renewable feedstocks to fuels. Where have you seen progress over time and what barriers still exist?

Joshua Messner: DOE has been working to produce biofuels for several decades, first working on first-generation corn ethanol technologies that are commercial today and found in gasoline all over the country. 

BETO’s long-term focus has been on second-generation biofuels production, expanding the feedstocks needed to produce biofuels, including sustainable aviation fuel (SAF). 

Feedstocks needed include municipal solid waste (MSW), agricultural residues, forest residues, and purpose-grown feedstocks like perennial grasses and algae.  Beyond increasing the feedstock pool this R&D will have significant GHG emission benefits over fossil fuels.

Much progress has been made on second-generation biofuels, and some technologies are ready for scaling-up to support their ultimate commercialization.

Financing for first-of-a-kind technologies is a barrier to commercializing biofuels. Government funding is helping by supporting costly pilot and demonstration-scale facilities, which are key to validating technologies before commercial investment. This is why we established a competitive scale-up strategy, which will help bioenergy companies that are ready to move their technologies from the laboratory to the pilot and demonstration stages between now and 2030.

Waste360: How did BETO come up with the goals of 70 percent reduction in greenhouse gas emissions (GHG) (vs. petroleum baseline) by 2030, and 90 percent GHG reductions by 2050? Why do you think they’re achievable?

Messner: BETO conducted a high-level life cycle assessment on leading biofuels technologies.  Due to continual technology improvements in both collection of the feedstock and conversion technologies, the assessments suggest as much as 70 percent reduction of GHG emission (vs. petroleum baseline) was achievable.  As more feedstocks and carbon capture technologies come online, we envision greater (90%) GHG emissions reductions.  To reach these reductions, the U.S. will have to continue to support biofuels RD&D.  Industry and investors will need to step up and commercialize these technologies as DOE will not be able to achieve these goals alone.

Waste360: Which transportation modes are hard-to-electrify and why? What’s the solution to decarbonizing those sectors?

Messner: Electrifying modes of transportation like aviation, maritime, rail, and heavy-duty applications is difficult due to the size and weight a battery would need to be to provide the required energy to perform.  For example, a cargo ship might need to use most of its cargo space for batteries to cross the Pacific Ocean, rendering it useless. Or an airplane would not be able to take off given the weight of a battery needed to provide enough power for lift off. The time to recharge or change out the batteries as well as the amount of renewable electricity it would take to charge these batteries is also a barrier. 

Light- and medium-duty vehicles can and will be more easily electrified, so the U.S. is focusing our vast renewable carbon resources on these more difficult to electrify sectors.  BETO’s research is primarily around drop in biofuels. Fuels produced from biomass have the same energy density, and other characteristics as petroleum fuels and can be used in existing engines and take advantage of much of the existing infrastructure that already exists. 

Waste360: Are biofuel costs dropping, and what must happen for this fuel to become cost-competitive with existing options?

Messner: Over the last decade BETO has been able to dramatically lower the cost of biofuels, from $6.27 per gasoline gallon equivalent (GGE) in 2014 to our newly met milestone of $2.91 per GGE for renewable diesel that can be made from anerobic digestor biogas.

This is only one of many potential pathways to produce fuel and continued work is needed to lower costs on the many feedstocks that can be utilized to produce all of the hard-to-electrify sectors’ fuel needs.  This includes R&D, as well as demonstration of fully integrated technologies so that commercial-scale facilities can be built and optimized such that biofuels will be able to compete in a commodities market.

Waste360: Why is BETO especially interested in agriculture waste and municipal solid waste for biofuel production?

Messner: In order to meet our volumetric goals of biofuels the U.S. will need as much renewable carbon as possible.  Our published Billion Ton Study shows that the U.S. has the potential to produce over 112 million dry tons of feedstock from municipal solid waste and crop residues by 2040 and an additional 54 million dry tons of feedstock from other waste feedstocks including forest residues and manures. This could represent 8.3 and 10 billion gallons of biofuels, which is a key to the U.S. meeting our 2050 goal.

Waste360: Tell us about the SAF (Sustainable Aviation Fuel) Grand Challenge.  What does it seek to solve/improve on?

Messner: The SAF Grand Challenge is the result of DOE, Department of Transportation (DOT), and the U.S. Department of Agriculture (USDA) launching a government-wide Memorandum of Understanding (MOU) that will attempt to reduce the cost, enhance the sustainability, and expand the production and use of SAF while achieving a minimum of a 50 percent reduction in life cycle greenhouse gas emissions compared to conventional fuel and meeting a goal of supplying sufficient SAF to meet 100 percent of aviation fuel demand by 2050.

The SAF Grand Challenge and the increased production of SAF will play a critical role in a broader set of actions by the U.S. government and the private sector to reduce the aviation sector’s emissions in a manner consistent with the goal of net-zero emissions for the U.S. economy, and to put the aviation sector on a pathway to full decarbonization by 2050.

The SAF Grand Challenge is currently working on a roadmap that we hope to publish this year. The roadmap will outline specific action areas, workstreams, and activities that need to be undertaken by the agencies, industry, national laboratories, and academia to achieve the volumetric goals.

Waste360: What can you tell us about some projects supported by BETO’s first funding opportunity announcement (FOA)?

Messner: With the first FOA ($64.7 million) we were able to select a strong portfolio of projects.  We selected eight pre-pilot projects which look to de-risk a process by focusing on one- or two-unit operations (one or two steps of an overall process), but not a whole system. These projects were diverse and included feedstocks like organic wet waste, biogas, municipal solid waste, waste carbon dioxide, agricultural residues, and purpose-grown energy crops. From these feedstocks these projects are looking to produce SAF and renewable diesel, as well as bioproducts like fertilizers and green plastics.

In addition to the pre-pilot projects, we selected one pilot-scale and two demo-scale projects.  These projects are currently in their first phase of work where they will design their facilities. Then a down-select will occur, where all, some, or none (subject to availability of funds and strength of project) of the projects will move into Phase 2 where they will construct and operate their Phase 1 designs.

The projects diversify the feedstocks we are evaluating and include corn stover to produce SAF, and landfill gas and biogas to produce SAF and diesel.