Company: TSLTF
Filing Date: 2025-12-12
Form Type: SUPPL
Source: 0001193125-25-317786
Chunk: 144

Company: TRANSALTA CORP
Filing Date: 2025-12-12
Form: SUPPL
Chunk 144
---
:

| • |     | Forecasts of sales prices for each facility are determined by taking into consideration contract                                                                                                                                                  
 prices for facilities subject to long- or short-term contracts, forward price curves for merchant plants and regional supply-demand balances. Where forward price curves are not available for the duration of the facility’s useful life, prices 
 are determined by extrapolation techniques using historical industry and Company-specific data. Merchant electricity prices used in Wind and Solar models ranged between $40 to $225 per MWh during the forecast period (2023 — $35 to $238 per   
 MWh).                                                                                                                                                                                                                                             |

| • |     | Discount rates used ranged from 6.4 per cent to 7.3 per cent (2023 — 6.4 per                                                         
 cent to 7.5 per cent). A 0.5 per cent increase in the discount rate would not impact the results of the impairments tests performed. |

| • |     | The White Rock and the Horizon Hill wind facilities are subject to location-specific price basis,                                                                                                             
 sourced from third-party analysis. This analysis is based on models of the transmission system, including assumptions around potential system upgrades as well as forecasted generation and load in the area. |

| TransAlta Corporation |     | 2024 Integrated Report |     | F72 |

Notes to the Consolidated Financial Statements 23. Other Assets The components of other assets are as follows:

| As at Dec. 31                                                 |     | 2024 |     |     | 2023 |     |
|:--------------------------------------------------------------|:----|:-----|----:|:----|:-----|----:|
| South Hedland prepaid transmission access and distribution    
 costs                                                         |     |      |  58 |     |      |  60 |
| TransAlta Energy Transition Bill commitment                   |     |      |  30 |     |      |  32 |
| Long-term prepaids and other assets                           |     |      |  35 |     |      |   9 |
| Project development costs                                     |     |      |  15 |     |      |  35 |
| Loans receivable                                              |     |      |  25 |     |      |  26 |
| Transmission infrastructure                                   |     |      |  17 |     |      |  18 |
| Total other assets                                            |     |      | 180 |     |      | 180 |
| Included in the Consolidated Statements