Profitability and scalability for waste-to-energy supply chains

Waste-to-Energy (WtE) conversion technologies have the potential to simultaneously reduce waste disposal costs, treatment-related emissions, and carbon intensity while producing valuable energy services. However, questions remain regarding the specific conditions under which emerging WtE technologies are feasible to deploy. In this paper, we develop an optimization-based siting method to assess cost-effective WtE processor locations, throughput scales, and profitability based on a geolocated waste inventory. Using Hydrothermal Liquefaction (HTL) as an example WtE technology, we develop calibrated scaled capital and operating expense cost curves based on literature data to study the techno-economic characteristics of WtE supply chains. In preparation for later solving the siting optimization, we use this paper to present and analyze the model that describes the behavior of the organic waste management system under four different HTL deployment configurations: Co-Processing, where HTL plants send biocrude to existing conventional refineries via assumed pipelines; Co-Location, where biorefineries must be integrated with HTL plants; and two alternative Standalone Biorefining cases, where distributed HTL plants transport biocrude intermediate via either assumed pipelines or trucking to centralized biorefineries. We also define several gate fee calculations representing different profit distribution options to investigate how bioproduct value could impact WtE supply chain economics in terms of waste producer and processor profit or cost reduction. The model and parameter analysis presented here serve as the basis for optimal WtE siting analyses to be presented in a subsequent paper.