US-REGEN Documentation

Resource and Technology Assumptions / Conversion

Bioenergy Refining/Conversion

Summary

Bioenergy feedstocks can be converted into end-use fuels via several so-called 'bio-refining' technologies. The model differentiates between currently utilized sources of bioenergy and potential new supplies. The former (current sources) includes corn-based ethanol, existing waste and residue biomass streams (such as wood-derived fuels consumed in the paper industry), and wood used for space heating in buildings. The latter (new supplies) includes incremental supply of methane from landfills and other wastewater and agricultural sources (referred to as waste methane) and cellulosic feedstocks from agricultural and other residues (excluding currently utilized waste streams), or from purpose-grown cellulosic energy crops (such as switchgrass) and logs.

For waste methane, the model includes a single conversion technology, namely the upgrading of landfill gas to a natural gas-equivalent fuel. For cellulosic feedstocks, the model includes a range of conversion technology options for producing "drop-in" equivalent hydrocarbon fuels, referred to as "renewable fuels". These include renewable natural gas, produced via gasification of cellulosic feedstocks, and renewable gasoline, diesel, and jet fuel, produced via a Fischer-Tropsch process. Each fuel conversion technology can be configured with or without carbon capture. Note that only carbon emitted during the refining process can be captured, not carbon embedded in the produced fuel. In the case of renewable jet fuel, it is assumed that the output is 50% jet fuel and 50% diesel, due to expected challenges in isolating jet fuel from the refining process. Conversion technologies are characterized in terms of the capital investment cost per unit of output capacity, fixed and variable operating costs, feedstock inputs (expressed in energy terms), and net inputs of electricity. In some cases, the technology is assumed to be a net producer of electricity due to opportunities for co-generation from waste heat.

Technology Cost and Performance

US-REGEN model assumptions for the costs and performance of bioenergy refining/conversion technologies over time are shown in the chart and table below. Use the buttons to choose a parameter to compare.

Capital Cost by Bioenergy Refining/Conversion Technology and Year
  • Chart
  • Table
Data Definitions

Measures

  • Capital Cost ($ per kBtu/h): Cost to bring a new bioenergy refining/conversion plant into operation, normalized to the plant's output capacity
  • Fixed Cost ($/year per kBtu/h): Annual fixed cost to operate and maintain the plant, normalized to the plant's output capacity
  • Variable Cost ($/MMBtu): Non-fuel variable cost to operate and maintain the plant per unit of fuel energy produced
  • Biomass Input (MMBtu/1 MMBtu biofuel): Total biomass energy input per unit of fuel energy produced
  • Capture Rate (tCO2/MMBtu): CO2 captured per unit of fuel energy produced

Bioenergy Refining/Conversion Technology

  • Upgrading of waste streams to RNG: Waste methane upgrading
  • R-gas: Bio-gasification (without carbon capture)
  • R-gas+CC: Bio-gasification (with carbon capture)
  • R-gasoline: Bio-based gasoline (eg F-T) (without carbon capture)
  • R-gasoline+CC: Bio-based gasoline (eg F-T) (with carbon capture)
  • R-diesel: Bio-based diesel (eg F-T) (without carbon capture)
  • R-diesel+CC: Bio-based diesel (eg F-T) (with carbon capture)
  • R-jet: Bio-based jet fuel (eg F-T) (without carbon capture)
  • R-jet+CC: Bio-based jet fuel (with carbon capture)