Oilcane—an oil‐accumulating crop engineered from sugarcane—and microbial oil have the potential to improve renewable oil production and help meet the expected demand for bioderived oleochemicals and fuels. To assess the potential synergies of processing both plant and microbial oils, the economic and environmental implications of integrating microbial oil production at oilcane and sugarcane biorefineries were characterized. Due to decreased crop yields that lead to higher simulated feedstock prices and lower biorefinery capacities, current oilcane prototypes result in higher costs and carbon intensities than microbial oil from sugarcane. To inform oilcane feedstock development, we calculated the required biomass yields (as a function of oil content) for oilcane to achieve financial parity with sugarcane. At 10 dw% oil, oilcane can sustain up to 30% less yield than sugarcane and still be more profitable in all simulated scenarios. Assuming continued improvements in microbial oil production from cane juice, achieving this target results in a minimum biodiesel selling price of 1.34 [0.90, 1.85] USD∙L−1(presented as median [5th, 95th] percentiles), a carbon intensity of 0.51 [0.47, 0.55] kg CO2e L−1, and a total biodiesel yield of 2140 [1870, 2410] L ha−1 year−1. Compared to biofuel production from soybean, this outcome is equivalent to 3.0–3.9 as much biofuel per hectare of land and a 57%–63% reduction in carbon intensity. While only 20% of simulated scenarios fell within the market price range of biodiesel (0.45–1.11 USD∙L−1), if the oilcane biomass yield would improve to 25.6 DMT∙ha−1∙y−1(an equivalent yield to sugarcane) 87% of evaluated scenarios would have a minimum biodiesel selling price within or below the market price range.
Although switchgrass has been developed as a biofuel feedstock and its potential for bioethanol and bio‐oil from fast pyrolysis reported in the literature, the use of the seeds of switchgrass as a source of triglycerides for biodiesel production has not been reported. Similarly, the potential for extracting triglycerides from coffeeweed (an invasive plant of no current economic value) needs to be investigated to ascertain its potential economic use for biodiesel production.
The results show that coffeeweed and switchgrass seeds contain known triglycerides which are 983 and 1000 g kg−1respectively of the fatty acids found in edible vegetable oils such as sunflower, corn and soybean oils. In addition, the triglyceride yields of 53–67 g kg−1of the seed samples are in the range of commercial oil‐producing seeds such as corn (42 g kg−1).
The results also indicate that the two non‐edible oils could be used as substitutes for edible oil for biodiesel production. In addition, the use of seeds of switchgrass for non‐edible oil production (as a feedstock for the production of biodiesel) further increases the total biofuel yield when switchgrass is cultivated for use as energy feedstock for pyrolysis oil and biodiesel production. © 2016 Society of Chemical Industry
- PAR ID:
- 10160882
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Journal of the Science of Food and Agriculture
- Volume:
- 96
- Issue:
- 13
- ISSN:
- 0022-5142
- Page Range / eLocation ID:
- p. 4390-4397
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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