Table 1 Selection of alternative maritime fuels in the research.
Category | Fuel technology | Primary resource | Characteristics | Sources | |
|---|---|---|---|---|---|
Postive | Negative | ||||
Fuel oils | HFO with scrubbers | Crude oil | Low cost, reduced SOx and NOx emissions; | Carbon-heavy, high viscosity bunker fuel | McGill et al. (2013), Mohseni et al. (2019), Endres et al. (2018), Ytreberg et al. (2019), |
Natural gases | LNG (Liquid-cooled methane/ethane gas) | Crude oil; natural gas | Low nitrogen oxide emissions, sulfur-free; low cost | High well-to-propeller GHG output | Burel et al. (2013), CE Delft et al. (2016), Pavlenko et al. (2020), Thomson et al. (2015), Brynolf et al. (2014), PICO and LORENZEN (2020) |
Bio-fuels | FAME (bio-diesel) | Edible or used oils | Suitable clean alternative to MDO/MGO | Risk of acidic degradation | Einemo (2017), Mohd Noor et al. (2018), Hsieh and Felby (2017), |
HVO | Edible or used oils | High-quality drop-in diesel fuel | Higher cost; cross-sector interest | Florentinus et al. (2012), DNV GL (2019), E4Tech (2018), Hsieh (2017) | |
UPO | Lignocellulosic; waste | Suitable clean alternative to HFO/IFO; high GHG reduction potential | Not commercially available | ||
UBO | Lignocellulosic; wet bio-mass; waste | High potential; more straightforward production process compared to UPO | Low commercialization | ||
FTD | Lignocellulosic; waste | Drop-in diesel fuel; very high GHG reduction potential | More impurities | Parraga (2018), E4Tech (2017), E4tech (2018), Tzanetis et al. (2017) | |
LBM (bio-LNG) | Lignocellulosic; landfill gas; waste | High GHG reduction potential | Potentially cost-competitive | ||
Ammonia | NH3 | Hydrogen | No tank-to-propeller emissions | High cost; toxic; low maturity in marine applications | Ash and Scarbrough (2019), DNVGL (2019), Hansson (2020a; b), E4tech (2018) |