This spreadsheet serves as an Input file to the National Renewable Energy Laboratory's Waste-to-Energy System Simulation (WESyS) model developed in Stella Pro (isee systems, Lebanon, NH). WESyS is a national-level system dynamics model that simulates energy production from three sectors of the U.S. waste-to-energy industry: landfills, confined animal feeding operations (CAFOs), and publically owned treatment works (POTWs).
For our purposes, a scenario is a set of model conditions (i.e. parameter settings) that approximate a specified condition or potential reality. The non-negative feedstock cost scenario outlined here represents a potential future reality where feedstock costs for waste become positive (i.e., there is a market for wastes). For the three types of facilities represented in WESyS (i.e., wastewater treatment plants, landfills, and concentrated animal feeding operations (CAFOs)), only CAFOs are expected to have positive feedstock costs for manure in the near future. If this were to happen, CAFOs might chose to sell their waste rather than build on-site waste-to-energy (WTE) facilities. For this scenario, we adopted a farmer-owned cooperative model in which farmers may sell their manure to a cooperatively owned and operated WTE facility. For these farmer-owned cooperatives, we have allow for technology development under three pathways (Hydrothermal Liquifaction (HTL), Fischer-Tropsch (FT), and Renewable Natural Gas (RNG)) that are assumed to operate at full commercial scale. For a given technology pathway to become feasible, there must be enough animal units available to supply the commercial throughput requirement of the technology.