A Model for Life Cycle Assessment of Transportation Fuels
what is GHGenius
GHGenius is a spreadsheet-based model for life cycle assessment of transportation fuels. Parameterized for Canada and expanded to model additional fuel pathways and scenarios. The model was developed by (S&T)2 Consultants for Natural Resources Canada. GHGenius can calculate energy and emissions associated with conventional or alternative fuel production for the past, present, and future (through 2050). Life Cycle Associates has extensive knowledge using GHGenius.
GHGenius includes the three traditional greenhouse gas emission constituents in addition to CFC-12 and HFC-134a; the model also includes criteria pollutants. GHGenius uses GWP values to aggregate greenhouse gas emissions to a total g CO2e value, although the model allows the input of CEFs or other metrics for aggregating emissions.
using GHGenius
The model workbook is organized with dozens of worksheets, similar to GREET, but the model is much more difficult to decipher than GREET. Some of the worksheets are labeled, but many are designated with only a letter, making it difficult to navigate the model and understand the linkages between worksheets. The lettered worksheets are not organized alphabetically or by any other obvious characteristic. This means that tracing the input parameters through the calculations to the finished results is quite difficult. However, the model does present WTT results by fuel pathway component (disaggregated results), a feature lacking in GREET.
Unfortunately, after navigating to a given worksheet described in the user-manual, the calculations included in the model are difficult to decipher. Moreover, fuel pathway calculations are spread across multiple worksheets (instead of organized in one sheet per fuel, like GREET) and much is accomplished using embedded macros.
The GHGenius model includes many alternative fuel pathways, but only models the fuels for light-duty vehicles, class 3 to 8 heavy-duty trucks, urban buses, light-duty BEVs, and FCVs. There are currently more than 200 vehicle, fuel, and feedstock combinations (pathways) represented in the model. GHGenius calculates results for several different regions of interest, including three sub-regions of Canada (east, central, and west), the United States, Mexico, and India.
data sources
Most of the U.S. data in GHGenius are derived from the EIA databases. These databases include historical data and future projections for electric power, crude oil, refined petroleum product, natural gas, and coal production. Other U.S. inventory data are sourced from the U.S. Census Bureau. The non-energy related process emissions in the model are based mostly on the EPA AP-42 emission factors.
For Canada, the data are derived from Statistics Canada, Natural Resources Canada, Environment Canada, the National Energy Board, the Canadian Association of Petroleum Producers, and the Canadian Gas Association. The emissions from vehicles for conventional fuels in Canada are derived from the Environment Canada model Mobile 6.2C.
For Mexico and India, the model adheres to a hierarchical method of obtaining inventory data, in which data are prioritized in the following order: industry average values, then actual operating plant operating data, then engineering design data, and finally estimated data from pilot plants, engineering simulations, or scientific experiments.
documentation
British Columbia’s Low Carbon Fuel Standard transitioned to using GHGenius version 5.02b in January 2024. The new version can be downloaded from the GHGenius website. Other key documentation for GHGenius includes a government of British Columbia guide to Using GHGenius in B.C. and a GHGenius Quick Start Guide.
Do you have questions on how to use GHGenius?