National security issues, economic stability, energy independence, and global climate change drive the need to develop new energy sources from sustainable, renewable resources. This need is particularly strong in the area of liquid transportation fuels. The key challenges to the large-scale production of high-energy-density biofuels are 1) the availability of additional scalable and environmentally sustainable biomass feedstocks which do not impact food production, 2) development of novel, cost-effective conversion technologies, and 3) compatibility with existing vehicles and distribution infrastructure. Macroalgae is an underexplored potential resource that merits more serious attention.
Project Innovation + Advantages:
E. I. du Pont de Nemours & Company (DuPont) and Bio Architecture Lab are exploring the commercial viability of producing fuel-grade isobutanol from macroalgae (seaweed). Making macroalgae an attractive substrate for biofuel applications however, will require continued technology development. Assuming these developments are successful, initial assessments suggest macroalgae aquafarming in our oceans has the potential to produce a feedstock with cost in the same range as terrestrial-based substrates (crop residuals, energy crops) and may be the feedstock of choice in some locations. The use of macroalgae also diversifies the sources of U.S. biomass in order to provide more options in meeting demand for biofuels. The process being developed will use a robust industrial biocatalyst (microorganism) capable of converting macroalgal-derived sugars directly into isobutanol. Biobutanol is an advanced biofuel with significant advantages over ethanol, including higher energy content, lower greenhouse gas emissions, and the ability to be blended in gasoline at higher levels than ethanol without changes to existing automobiles or the fuel industry infrastructure. Butamax is currently commercializing DuPont's biobutanol fermentation technology that uses sugar and starch feedstocks.
If successful, the production of macroalgal-derived isobutanol has tremendous global application and potential as a large-scale, renewable energy technology.
Fermentable sugars may be produced domestically at a large scale from macroalgae and will not compete with the production of terrestrial food crops. Isobutanol has the potential to replace more than 15 billion gallons of gasoline/year.
Isobutanol derived from macroalgae is projected to deliver greenhouse gas reductions when compared to gasoline derived from petroleum. Macroalgae aquafarming may also help remediate coastal dead zones.
The production of isobutanol, an advanced biofuel, is a transformational energy product/process that offers significant advantages over ethanol and can help accelerate biofuels adoption globally. Compared to ethanol, biobutanol has a higher energy content which means better fuel economy for vehicles running on butanol and butanol blends. It can also be pre-blended with gasoline for easier distribution as it is compatible with existing refinery processes.