| CFPP location | Ash Yield | Ash Class Category (According to ISO 11760:2005) [21] |
| Witbank | 25.27% (≥20 and <30) | Moderately high ash |
| Waterberg | 32.84% (≥30 and <50) | High ash |
| Sasolburg | 40.85% (≥30 and <50) | High ash |