FARMDYN
a dynamic mixed integer bio-economic farm scale model
FARMDYN provides a flexible, modular template to simulate farms with different branches (dairy, mother cows, beef fattening, pig fattening, piglet production, arable farming, biogas plants)
Main characteristics
- Fully dynamic, simulations typically cover several decades, alternatively comparative-static or short run version
- Integer variables capture Returns-to-scale in investments (machinery, buildings; based on convex combinations over a concave set) and indivisibilities in labour use
- Selected farm management decisions (e.g. feeding, manure management, labour use) depicted with a sub-annual temporal resolution, partially bi-weekly
- Deterministic or stochastic programming version. The latter treats all variables as state dependent, allows for sceneario tree reduction and covers different risk measures (value at risk, MOTAD ...)
- Farm labour, machinery and stable use are modelled in rich detail
Arable cropping can be differentiated by system (conventional or organic), tillage type and intensity
- For dairy farming, the model distinguishes several herds by number of lactations and lactation phase
- Beef fattening can be depicted in several phases, linked to different grazing options, considering cross-breeding and sexing
- The machinery park is available in different mechanization levels
Detail in grassland management (number of cuts, bales/silo/hay etc.) - Highly differentiated modules for nitrogen fate, while covering German legislation on fertilizer use
- A range of economic, social and environmental indicators, including LCA derived ones
Model documentation
The detailed model documentation is available as a Website and as printable PDF.
The documentation refers to a stable release of FARMDYN which represents a properly tested and documented version of the model (launched in September 2016, model revision 500):
Britz W., Lengers, B,.Kuhn, T. and Schäfer, D. (2014): A highly detailed template model for dynamic optimization of farms - FARMDYN, University of Bonn, Institute for Food and Resource Economics, Version September 2016, 147 pages.
FARMDYN contains several features that are currently developed (flagged in documentation as prototype) or not used anymore (flagged as deprecated). These features have not been subject to the intensive testing for the stable release. They are only visible in the developer mode of FARMDYN and listed in the stable release information.