Panamax container ship decarbonization: Lifecycle emissions, ownership costs, and break-even carbon pricing

Carbon pricing may shift fuel choice without selecting the lowest-emission pathway. We evaluate heavy fuel oil (HFO), liquefied natural gas (LNG), hydrotreated vegetable oil (HVO), green hydrogen, and green ammonia for a 4,253 TEU Panamax ship on the Singapore–Tokyo route, 2026–2050. The framework combines total cost of ownership (TCO), well-to-wake (WtW) emissions, cargo-capacity loss, transition timing, and two-tier fuel-intensity pricing. Without pricing, HFO minimizes TCO and emits 5,206.3 kt CO 2 e. At Tier 1 and Tier 2 prices of US$100/t CO 2 e and US$380/t CO 2 e, LNG Newbuild 2026 minimizes TCO. For a 10-year-old vessel, it reduces emissions by 11.8% but raises TCO by 89.5% over no-policy HFO. HVO switching in 2026 reduces emissions by 78.2%. Raising Tier 1 lowers LNG’s Tier 2 threshold but raises parity TCO. Appraisal should consider thresholds, ownership costs, and lifecycle emissions.