BioFuels
Biomass Farming
The bio-masses used for the bio-fuels pathways are:
- Soybean
- Palm FFb
- Rapeseed
- Jatropha
- Camelina
All those farming processes are implemented in GREET. They are using regular US averages fertilizer production and Diesel for non road engine to power the farming tractors and other stationary engines used (pumps, conveyors...)
The products are assumed to be transported dried so there is no need to specify the moisture content of those materials in the transportation processes after those farming processes.
Bio-fuels production
Bio-fuels production generates a lot of valuable co-products such as SBM or Glycerine. In the Excel spreadsheet options are offered on the main page to switch between system level allocation or process level allocation/displacement. In GREET we choose to treat that as two different sets of processes/pathways.
For the process level allocation/displacement method we create two distinct processes Oil Extraction and Transesterification. Each of them have their set of inputs and a definition of the co-products. It is therefore allowed to perform an displacement on the first process and a market allocation on the transeterification process, the treatment method chosen for each process is independent.
If the model chosen is a system level allocations the extraction and transesterification processes are modeled as a single process with two co-products. They are aggregated in a single process to make abstraction of the vegetable oil link between the extraction and trans. processes, thus making them a single system.
Biodiesel from Soybeans (Process Level)
Description of the biodiesel from soybeans pathways using process level allocation/displacement in GREET.