Advantages
ZeaChem's new approach to cellulosic ethanol provides technological, economic and environmental advantages compared to traditional ethanol and other cellulosic ethanol processes.
Process
ZeaChem uses a hybrid approach; the biochemical pathway for the most efficient fermentation with respect to carbon conversion (ZeaChem's acetogenic process produces no CO2) and then a thermochemical pathway for hydrogen production from the non-sugar lignin stream. For every bone dry ton (BDT) of feedstock, ZeaChem's technology will produce a theoretical maximum of 156 gallons of ethanol, with an expected yield of approximately 135 gallons per BDT (gal/BDT). Accounting for yield per acre, this is five times more than corn based ethanol processes and about three times more than other cellulosic processes, either biological (enzymatic) processes or thermochemical (gasification) processes. ZeaChem's high-yield process gives it sustainable competitive advantage in both economics and environmental impact.
As the graph below demonstrates, advances in ethanol technology and auto efficiency can increase land productivity by a factor of 10.
| Farm Yield | Factory Yield | Auto Efficiency | Land Productivity | |
|---|---|---|---|---|
| Corn Ethanol | 150 Bu/ac/yr | 2.7 Gal/bu | 14 mi/Gal EtOH | 5,670 mi/ac/yr |
| Cellulosic Ethanol¹ | 7.5 BDT/ac/yr | 90 Gal/BDT | 14 mi/Gal EtOH | 9,450 mi/ac/yr |
| Advanced Cellulosic Ethanol (ZeaChem Inc).² |
15 BDT/ac/yr | 135 Gal/BDT | 14 mi/Gal EtOH | 28,350 mi/ac/yr |
| Advanced Cellulosic Ethanol + Auto Efficiency | 15 BDT/ac/yr | 135 Gal/BDT | 25 mi/Gal EtOH | 50,625 mi/ac/yr |
¹ Biochemical, thermochemical or syngas fermentation average
² Hybrid combination of biochemical and thermochemical processes
Economic
ZeaChem's advantage in operating costs puts its process at a competitive advantage to both corn based ethanol producers and cellulosic ethanol competitors. Given its 40% yield advantage, ZeaChem's process has the lowest operating (<$1.00) and capital cost (<$4.00) per gallon. Assuming a yield of 15 BDT/acre, a biomass farm with an approximate 5 mile radius could support a ZeaChem biorefinery with capacity of 100 million gallons per year (MM GPY). This translates into net land productivity rates nearly five times higher than existing approaches.
Environmental
The ZeaChem process results in a high yield of ethanol per ton of feedstock because the process efficiently utilizes all fractions of the feedstock. The effectiveness of this process results in a fuel that, when substituted for traditional corn-based ethanol or gasoline, will produce substantial verifiable carbon emission reductions. Compared to gasoline, ZeaChem's Process delivers a 94-98% reduction in greenhouse gases as calculated by the US Department of Energy/Argonne Labs GREET Analysis.