# Problem Formulation

**Download the updated Challenge 3 Problem Formulation document dated January 22, 2024. **Expanded Introduction (Section 1) and added Problem Description (Section 2).

The Change Log (Section 9) lists the major changes since the original was posted.

The original version had multi-mode devices, which were conceived of as a means for modeling combined cycle generators and storage devices. In the current version of the formulation, multi-mode devices have been removed. Combined cycle generators, storage devices, and multi-mode devices may be added to future Challenges.

The previous Challenge 3 Problem Formulation document dated May 15, 2023 is still available.

The previous Challenge 3 Problem Formulation document dated January 26, 2023 is still available.

The previous Challenge 3 Problem Formulation document dated January 13, 2023 is still available.

The previous Challenge 3 Problem Formulation document dated January 6, 2023 is still available.

The previous Challenge 3 Problem Formulation document dated July 1, 2022 is still available.

The original Challenge 3 Problem Formulation document dated February 16, 2022 is still available.