Sets and Parameters - iea-etsap

1 Introduction
The purpose of the Reference Manual is to lay out the full details of the TIMES model,
including data specification, internal data structures, and mathematical formulation of the
model’s Linear Program (LP) formulation, as well as the Mixed Integer Programming (MIP)
formulations required by some of its options. As such, it provides the TIMES
modeller/programmer with sufficiently detailed information to fully understand the nature and
purpose of the data components, model equations and variables. A solid understanding of the
material in this Manual is a necessary prerequisite for anyone considering making
programming changes in the TIMES source code.
The Reference Manual is organized as follows:
Chapter 1 Basic notation and conventions: lays the groundwork for understanding the
rest of the material in the Reference Manual;
Chapter 2 Sets: explains the meaning and role of various sets that identify how the
model components are grouped according to their nature (e.g. demand
devices, power plants, energy carriers, etc.) in a TIMES model;
Chapter 3 Parameters: elaborates the details related to the user-provided numerical data,
as well as the internally constructed data structures, used by the model
generator (and report writer) to derive the coefficients of the LP matrix (and
prepare the results for analysis);
Chapter 4 Variables: defines each variable that may appear in the matrix, both
explaining its nature and indicating how if fits into the matrix structure;
Chapter 5 Equations: states each equation in the model, both explaining its role, and
providing its explicit mathematical formulation;
Chapter 6 The User Constraints: explains the framework that may be employed by
modellers to formulate additional linear constraints, which are not part of the
generic constraint set of TIMES, without having to bother with any GAMS
programming;
Chapter 7 The Lumpy Investment facility, and
Chapter 8 The Endogenous Technological Learning capability.
1.1 Basic notation and conventions
To assist the reader, the following conventions are employed consistently throughout this
chapter:
• Sets, and their associated index names, are in lower and bold case, e.g., com is the set
of all commodities;
• Literals, explicitly defined in the code, are in upper case within single quotes, e.g.,
‘UP’ for upper bound;
• Parameters, and scalars (constants, i.e., un-indexed parameters) are in upper case, e.g.,
NCAP_AF for the availability factor of a technology;
• Variables are in upper case with a prefix of VAR_, e.g., VAR_ACT corresponds to the
activity level of a technology.
• Equations are in upper case with a prefix of EQ_ or EQ(l)_ with the placeholder (l)
denoting the equation type (l=E for a strict equality, l=L for an inequality with the left
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