The California Air Resources Board (ARB) staff has posted two new fuel pathway applications submitted under the California Low Carbon Fuel Standard (LCFS) Method 2 pathway approval process: one for dehydrated Brazilian sugarcane ethanol produced by a company in Costa Rica, the other for domestic corn ethanol.
LAICA. Liga Agricola Industrial De La Cana de Azucar (LAICA) operates an ethanol dehydration plant in Punta Morales, a town in the Puntarenas province of Costa Rica. LAICA dehydrates imported Brazilian hydrous sugarcane ethanol (95% ethanol) at its Punta Morales plant. Dehydration is accomplished using molecular sieves.
Oceangoing tankers transport hydrous ethanol from Brazil to the LAICA plant, and anhydrous product (99.5% ethanol) from that plant to California. LAICA uses bunker fuel as the energy source for the plant’s boiler. Steam from the boiler serves as the heat source for the molecular sieves and is also used to cogenerate electricity. The dehydration stage CI calculated in this analysis is added to the existing Low Carbon Fuel Standard LCFS CIs for the three Brazilian sugarcane ethanol pathways (average baseline production; electricity export; mechanized harvesting and electricity export).
The proposed LAICA pathway adds 11.31 gCO2e/MJ to the three pathways, resulting in final carbon intensities of 84.71, 69.71, or 77.71 gCO2e/MJ, depending upon the specific conditions.
Trenton Agri Products. Trenton Agri Products, LLC (TAP) produces ethanol from corn at a dry mill plant in Trenton, Nebraska. The TAP plant is an ICM-designed facility with a nameplate capacity of 40 million gallons per year of denatured ethanol. The plant is a natural gas-fired facility producing both wet and dry distiller’s grains with solubles (DGS).
TAP reports that most of the DGS it produces is wet DGS (requiring no drying, i.e., no natural gas and electricity consumption by the dryer), while the remainder is dry DGS,depending on market demand.
Although the TAP plant is able to receive feedstock by rail, CA-GREET feedstock transport default values were used to calculate the plant’s pathway carbon intensity (CI). Because those defaults assume truck transport of feedstock, the transportation component of the plant’s proposed CI may be slightly higher than its actual CI, staff noted.
TAP is applying for two pathway CIs: one associated with dry DGS production (88.39 gCO2e/MJ) and the other with wet DGS production (79.99 gCO2e/MJ). The reference pathways for TAP’s proposed pathways are two Midwest dry mill, natural gas pathways: the dry DGS pathway with a CI of 98.4 and the wet DGS pathway with a CI of 90.1. Both TAP pathways improve upon their reference pathway CIs by more than the requisite five grams of CO2e/MJ.
These CI improvements were made possible by the plant’s efficient design. ICM Inc. designed TAP to achieve reductions in both thermal and electrical energy consumption. As a result, it improves upon both the thermal and electrical energy use levels assumed for the reference pathways (32,330 BTU per gallon thermal energy use for the dry DGS pathway and 1.08 kW-hr per gallon for both pathway.
Upon posting on the LCFS website, these pathways and their associated carbon intensity values may be used for reporting and credit generation purposes prior to adoption and incorporation into the LCFS regulation.