| Clue | Source | Date |
|---|---|---|
| Fuel alternative beside oil | The Telegraph Cryptic | 22 Jan 2026 |
| *Plant-derived fuel | ||
| Modern renewable fuel | LA Times Daily | 11 Sep 2018 |
| Modern renewable fuel | The Washington Post | 11 Sep 2018 |
| Modern renewable fuel | ||
| Fuel made from vegetable sources (and a 2006 dictionary addition) |