ARPA-E hosted an event in its public workshop series – “Applied Biotechnology for Transportation Fuels: Meeting Today¹s Energy Needs by Maximizing Photon Capture,” on December 2-3, 2010, in Arlington, VA. The workshop brought together thought leaders from distinct science and engineering communities to develop new ideas and identify practical approaches toward increasing the efficiency of light collection by biological systems and the conversion of that energy into liquid forms of chemical energy that can be used for transportation. Focus was directed towards the production of high-energy content fuel molecules by photosynthetic systems rather than processes that convert lignocellulose or other sources of biomass to usable fuels.  

Specifically, ARPA-E was interested in exploring interdisciplinary project opportunities that combine genomic information, genetic engineering, classical genetic selection, and photobiophysics for:

• Increasing productive light absorption – How can organisms be engineered to better use the available solar resource for significantly enhanced production of biofuels?  Topics included: expanding the photosynthetically active spectrum, altering the photoprotective response, tailoring the structure and composition of organisms to better capture light, and the introduction of light-powered proton pumps.
• Altering organism metabolism to increase the energy captured as liquid fuels – After light energy is captured, how can the ideal biological system for the production of biofuels be created?  Topics included: capture of high-energy intermediates, alternatives to RuBisCO carbon fixation, bypassing photorespiration, and redirecting resources towards optimal fuel production.
• Applying novel genetic selection strategies to optimize fuel production strains – How can novel selection or screening strategies be employed to favor increased liquid fuel yields? Topics included: development of stable symbiotic co-cultures that increase fuel production, adaptation of production organisms to stresses that favor overproduction of fuel molecules, and sexual selection strategies based on increased energy yields.

Special attention was directed towards identifying low-cost, scalable strategies to develop highly efficient photosynthetic systems quickly, without requiring extensive, basic, R&D. In general, ARPA-E supports projects that have a high degree of technical or execution risk, beyond the range of typical government R&D funding.

Proceedings from the meeting are summarized below. View the workshop agenda (pdf). 

Speakers and Presentations:

1. Dr. Mark Hartney, Program Director, ARPA-E - Welcome (pdf)

2. Dr. Jonathan Burbaum, Program Director, ARPA-E - Workshop Introduction (pdf)

3. Dr. Don Ort, University of Illinois at Urbana-Champaign - What is the Maximum Efficiency that Photosynthesis Can Convert Solar Energy into Biomass? (pdf)

4. Dr. Tasios Melis, University of California, Berkeley - "Photosynthesis to Fuels”: Enhancing Fuel Production in Cyanobacteria and Microalgae (pdf)

5. Dr. Ganesh Kishore, Malaysian Life Sciences Capital Fund - What Does it Take to Feed and Fuel the World with Agriculture? (pdf)

Workshop Output Report (pdf)

Morning Breakout Sessions:

During the morning, participants broke into three sets of breakout sessions focusing on:

• Increasing productive light absorption – How can organisms be engineered to better use the available solar resource for significantly enhanced production of biofuels?  
• Altering organism metabolism to increase the energy captured as liquid fuels – After light energy is captured, how can the ideal biological system for the production of biofuels be created?  
• Applying novel genetic selection strategies to optimize fuel production strains – How can novel selection or screening strategies be employed to favor increased liquid fuel yields? 

The goal of the morning was to develop new ideas and identify practical approaches toward increasing the efficiency of light collection using biological systems and the conversion of that energy into liquid forms of chemical energy that can be used for transportation.  Direct production of high-energy content fuel molecules with photosynthetic systems was the primary focus rather than processes that convert lignocellulose or other sources of biomass to usable fuels.  Workshop attendees discussed opportunities to combine genomic information, genetic engineering, and classical genetic selection to accomplish these goals and the tools required to realize them.

Overarching Questions or Discussion Topics:

• What are the quantitative (theoretical) limits of the technology?
• If the technology improvement works at 100%, what would the impact on fuel yield be?
• What factors might reduce this impact, and how might they be quantified?
• How can we reduce these ideas to practice?
• Is the idea science, engineering, or both?
• Is a technology breakthrough in a 3-5 year timeframe realistic?
• What are the aspects of the technology that constrain development?
• Are there advances in related fields that could shorten the timeline? 

Afternoon Breakout Sessions:

Attendees were split into three groups consisting of an even distribution of workshop participants from each of the morning breakout sessions.  Drawing on the morning discussions, each group was tasked with designing an innovative photosynthetic process that would produce a liquid biofuel directly from sunlight and ambient CO2 and scale to production quantities.  Attendees were encouraged to be imaginative and explore new and creative ideas despite their perceived level of practicality.  Each group was assigned one of three source organisms to use for their implementation – a C4 plant, an aquatic phototroph, or a non-photosynthetic “model” organism.  After generating their organism and production process, the three groups presented their ideas to all attendees in turn for questioning and debate.