(562ae) An Excel Tool for Economic and Environmental Analysis of Waste-to-Energy Technologies Processing Urban and Rural Waste

The average amount of waste generated in the United States is 4.4 lbs./day/person ¹, and most of it is landfilled. The enormous amount of energy contained in these wastes presents an opportunity for renewable energy production. Renewable energy production methods that are more environmentally friendly are needed to address concerns about global warming. Therefore, it is necessary to explore opportunities to implement waste to energy technologies that will reduce landfilling and minimize environmental impact. An Excel-based calculator has been developed to compare various options for waste to energy conversion. In this poster, the methodology used to create this tool and some case studies that illustrate its use will be presented.

The options for converting waste to energy include anaerobic digestion (AD), incineration and gasification. In addition, landfilling followed by landfill gas collection and conversion is also often practiced. These landfill gases can be purified and upgraded to be used in energy recovery methods like combined heat and power units (CHP), Fischer-Tropsch Synthesis (FTS) to produce liquid fuel or the production of Compressed Natural Gas (CNG).

Most of these technologies are new and minimal data has been reported for the operation of these plants. A limitation encountered when trying to decide which of these technologies should be implemented is that there is no set tool that compares and analyses the techno-economic data and fuel-cycle environmental impact of these plants. Analyzing data from plants currently operating can provide data used to estimate cost and GHG emissions for the screening of these alternative projects. The goal of this project is to create a software tool that compiles all this data to assist decision makers such as municipalities and waste management companies on the selection of waste to energy technologies.

Using this tool, the user can select the technology desired: AD, Gasification, Incineration or Landfilling, as well as the energy recovery method: CHP, liquid fuel or CNG production. The user will also provide the feedstock type (Municipal Solid Waste (MSW), Food Waste, Animal Manure, and Farm Waste), feed properties and plant capacity. The software tool is set to provide the user with the capital and operational cost estimates, biogas production rate and its composition, and where applicable, liquid and solid production rates. The calculator also provides detailed fuel-chain analyses of the environmental impact and GHG emission savings for the use of each technology compared against fossil fuel sources and landfilling of waste.

In this presentation, we will discuss the underlying principles and methods used in building this calculator. In addition, we will present results for a case study involving the waste disposal options for Hillsborough County located in Florida.

References

1. (2013, March 27). Municipal Solid Waste. Retrieved from https://archive.epa.gov/epawaste/nonhaz/municipal/web/html/