Undergraduate Projects

Biofuel Composite Curve for Supply Chain

One of the major cost components of biofuel production involves the cultivation, harvesting, and transportation of biomass feedstock. Using an Excel-VBA interface, we optimize the transportation costs of biomass from farms to a given biorefinery by generating a procurement plan and composite curves. The procurement plan indicates which farms (or farm regions) should ship biomass, while the composite curves indicate the optimal transportation cost and the amount of biomass to be shipped from each farm. Furthermore, the interface has the option to optimize the biorefinery location based on feedstock availability.

Biofuel composite curve for supply chain interface
Figure 1. Excel interface showing the input section on the left, the farm regions on the center, and the resulting composite curve for the current biorefinery location on the right

Biofuel Supply Chain Design Under Uncertainty

When designing a supply chain for the production of biofuels, there are many sources of uncertainty that can influence the solution. Previous stochastic models account for the effects of uncertainty related to biomass seasonality and agricultural district (Figure 2a). In this work, we develop a stochastic model that accounts for temporal uncertainty (i.e., crop availability over the years) which often results in highly distributed biomass availability maps (Figure 2b).

Crop availability maps
Figure 2. (a) Wisconsin agricultural districts; (b) crop availability map of a specific scenario.


Identifying Promising Bio-based Chemicals

We developed an Excel-VBA interface to rapidly identify promising bio-based chemicals based on their price, US demand, and market size. A user can fine-tune the identification process through the selection of different criteria and the corresponding threshold values. The interface displays a list of bio-based chemicals satisfying the selected criteria and graphs to aid in the selection of chemicals (Figure 3).

Sample results
Figure 3. Results generated for chemicals with a price higher than 70 cents/lb and a market size larger than $300M/year. (a) List of bio-based chemicals satisfying the criteria; and (b) graph of price vs. demand with market size curves showing the bio-based chemicals (orange diamonds) satisfying all requirements