
Biofuels with By-Products, July, 2010

(References and background documentation at the bottom of this page.)

This version was developed for analysis of the global land use impacts of biofuels.
It has a base year of 2001 -- the latest year for which a global land use data base is available for cropland use (harvested area and yields).
Subsequent to model simulation, adjustments can be made to reflect the increase in feedstock yields since that time.

Experiments are available:

Long =  boost production of corn ethanol from 1.75 bgy in 2001 to the 2015 mandated level of 15 bgy.

Short = boost production of corn ethanol from 1.75 bgy to 2.75 bgy.

Fix_Food = boost production of corn ethanol from 1.75 bgy in 2001 to the 2015 mandated level of 15 bgy, while keeping food consumption constant

To run each of these experiments, go to the main screen and select the "SOLVE" tab. Then LOAD the appropriate experiment file and click the SOLVE button.

Common problems with a new installation:

0. To run this model, you should have a GTAP data base license (version 6 or 7). This may be obtained at:

https://www.gtap.agecon.purdue.edu/databases/v7/default.asp

1. You will need a license file for the GEMPACK software suite used to solve this model. To obtain a license vist:

http://www.monash.edu.au/policy/gpres.htm

2. You will want to "turn off" all the auxilliary programs other than the main model. To do so, go to the drop-down menu for version (this is not the Version tab which you are currently in). Select "modules" and turn off every module excepting the main model.

You can permanently do this by setting no in the version specific settings.  This is helpful because it means that when you go to run other applications you will revert back to running all the modules, as they are only turned off for your application. 

3. Be sure to increase the maximum simulation time. To do so, go to tools|options and set the maximum simulation time to 99999.


---------------------- Documentation follows ----------------------------------------------------------------------------------------------------

GTAP Model and Data Base used in the Biofuels Impact Analyses for CARB

The great strength of the standard GTAP model (Hertel, 1997) is the fact that it is well-documented, publicly available, widely used and readily modifiable for special purpose applications. In this work we begin with GTAP-E model and modify it for the purpose of analyzing biofuels. The data base is also extended in order to improve the treatment of biofuel by-products and accurately represent global land use.

The modified model is nick-named GTAP-BIO (Birur et al., 2008). GTAP-BIO incorporates many features of the GTAP-E model designed for climate mitigation policy.  The GTAP-E model was developed by Burniaux and Truong (2002) and modified by McDougall and Golub (2009). Birur et al. (2008) further modified the GTAP-E model to incorporate the potential for biofuels to substitute for petroleum products.  They also alter the energy demand elasticities based on an historical validation exercise undertaken by Beckman and Hertel (2009).

A very important feature of biofuel production is existence of by-products, which often compete with the feedstock in feed use. In the case of corn ethanol, the by product is called Dried Distillers Grains with Solubles (DDGS). We build on the work of Taheripour et al. (2008) in incorporating biofuel by-products in our modeling framework and analysis. They modified the GATP-BIO model to handle production, consumption and trade of biofuel by-products. 

The core data base used in the analysis is the GTAP version 6 global economic data base (Dimaranan, 2006). The version 6 data base is licensed and individuals seeking to replicate this work will need a license to the GTAP data base. 

Taheripour et al. (2007) introduced biofuels into this database. The modified data base includes data on production, consumption and trade of biofuels including grain based ethanol, sugarcane ethanol, and biodiesel from oilseeds for 2001. 

In order to elicit the global land use impacts of biofuel production, we have drawn on the publicly available land use data bases developed by Navin Ramankutty and collaborators (Ramankutty et al., 2008; Monfreda et al., 2008). These are brought into the GTAP framework following the approaches outlined in Lee et al. (2009).  

References
Beckman, J. F. and T. W. Hertel (2009) "Why Previous Estimates of the Cost of Climate Mitigation are Likely Too Low". GTAP Working Paper No. 54, Center for Global Trade Analysis, Purdue University, West Lafayette, IN.  

Birur, D.K., T.W. Hertel and W.E. Tyner (2008) "Impact of Biofuel Production on World Agricultural Markets: A Computable General Equilibrium Analysis". GTAP Working Paper No. 53, Center for Global Trade Analysis. Purdue University, West Lafayette, IN.
https://www.gtap.agecon.purdue.edu/resources/download/4034.pdf

Burniaux, J. M. and T. Truong (2002) "GTAP-E: An Energy-Environmental Version of the GTAP Model", GTAP Technical Paper No. 16, Center for Global Trade Analysis.  Purdue University, West Lafayette, IN, USA.  https://www.gtap.agecon.purdue.edu/resources/res_display.asp?RecordID=923 

Dimaranan, B. V., Editor (2006). "Global Trade, Assistance, and Production: The GTAP 6 Data Base," Center for Global Trade Analysis, Purdue University, West Lafayette, IN, USA.  

Hertel, T.W. (1997)  "Global Trade Analysis, Modeling and Applications." Cambridge University Press, Cambridge. 1997. For the latest version of the model, see GTAP Model.

GTAP model (2007), maintained by the Center for Global Trade Analysis, Purdue University.
Latest version is available for download at https://www.gtap.agecon.purdue.edu/models/current.asp 

Lee, H.L., T. W. Hertel, S. Rose and M. Avetisyan (2009) "An Integrated Land Use Data Base for CGE Analysis of Climate Policy Options," Chapter 4 in: Economic Analysis of Land Use in Global Climate Change Policy, edited by, T.W. Hertel, S. Rose and R. Tol, UK: Routledge Press. In press, currently available at: https://www.gtap.agecon.purdue.edu/resources/res_display.asp?RecordID=2603 

McDougall, R. and Golub, A. (2009). "GTAP-E Release 6: A Revised Energy-Environmental Version of the GTAP Model", GTAP Research Memorandum No. 15, Center for Global Trade Analysis.  Purdue University, West Lafayette, IN, USA. 

Monfreda, C., N. Ramankutty, and J.A. Foley (2008), "Farming the Planet 2: The Geographic Distribution of Crop Areas and Yields in the Year 2000." Global Biogeochemical Cycles, 22, GB1022, doi:10.1029/2007GB002947.

Ramankutty, N., A.T. Evan, C. Monfreda, and J.A. Foley (2008), Farming the Planet 1: The Geographic Distribution of Global Agricultural Lands in the Year 2000. Global Biogeochemical Cycles, 22, GB1003, doi:10.1029/2007GB002952.

Taheripour, F., D. K. Birur, T.W. Hertel, W.E. Tyner (2007) "Introducing liquid biofuels into the GTAP data base", Research Memorandum 11. Center for Global Trade Analysis, Purdue University, West Lafayette, IN, USA. 

Taheripour,  F., T.W. Hertel, W.E. Tyner, J.F. Beckman, D.K. Birur (2008) "Biofuels and their By-Products: Global Economic and Environmental Implications".  Paper Presented at the 11th  GTAP Conference, June 12-14 2008, Helsinki, Finland and at the 2008 American Agricultural Economics Association meeting in Orlando, Florida. https://www.gtap.agecon.purdue.edu/resources/download/3974.pdf
