I have developed or co-developed several models related to the life cycle assessment of biofuels. EBAMM, BEACCON, and GBAMM are all derivatives of GREET, developed for specific purposes, such as meta-model comparisons (EBAMM and GBAMM) or biorefinery technology and cost comparisons (BEACCON).
All of these open-source models were developed in Excel® and are accompanied by peer-reviewed papers. Download links are provided below.
RFMI is a simple 9-parameter model of emissions from indirect land use change, which I exercise using Monte Carlo simulation to examine the shape of possible frequency distributions for ILUC emissions. Download the model: RFMI_pub_v1.xlsm (205 KB)
BTIME estimates a novel measure of biofuel GHG performance modeled after the IPCC's Global Warming Potential (for better and worse.) The model tracks the cumulative CO2 emitted overthe life cycle of biofuel--including assumed emissions from indirect land use change--and gasoline, accounting for the time of emissions and atmospheric decay of CO2. For more details, see the paper and model, downloadable from the RAEL website.
GBAMM is conceptually similar to the EBAMM model (discussed below). Where EBAMM was developed to compare six studies of the energy and GHG balances of corn ethanol, GBAMM was developed to compare two specific models, BESS and GREET. However, while EBAMM compared net energy models of ethanol, providing GHG accounting based on GREET, GBAMM compares two models of the GHG balances of ethanol, and thus compares GHG emission factors as well.
The model and paper can be downloaded from this site.
BEACCON allows ethanol producers to evaluate the potential impacts on production costs of the global warming intensity (GWI) of different biofuel production pathways. Version 1.0 of the model focuses on ethanol plants with a capacity of 100 million gallons per year. BEACCON may be downloaded free of charge.
BEACCON calculates the production costs of ethanol taking into account plant capital costs, corn costs, energy feedstock costs, labor, chemicals, and other cost components, as well as energy system costs taking into account energy system capital costs, thermal fuel and electricity feedstocks. It also calculates the GWI of ethanol on a life cycle basis by major contributing components: agricultural phase, thermal energy feedstocks, and grid electricity.
EBAMM was developed to understand the large divergence between studies of the net energy balance of corn ethanol. The model puts six studies into a common framework, converts all data to international standard (SI) units, and establishes consistent system boundaries -- all of which are prerequisites to comparing results and identifying differences among the models.