High temperature fuel cells to reduce CO₂ emission in the maritime sector

¹ Ecospray Technologies s.r.l., Alzano Scrivia (AL), Italy
² Department of Civil, Chemical and Environmental Engineering (DICCA), University of Genoa, Genoa, Italy

^* Corresponding author: barbara.bosio@unige.it

Abstract

Recently the interest in the sustainability of the maritime sector has increased exponentially. The International Maritime Organization (IMO) set as objective the reduction of CO₂ emissions by 2030 by a margin of 40% compared to 2008. Recent studies showed that, according to the ships and the emission mitigation method applied, only 15–25% of CO₂ reduction is de facto needed. Fuel cells represent an answer to meet this regulation. We propose two different solutions: (i) produce with SOFCs instead of engines the minimum power necessary to cut 20% of the emissions, or (ii) reduce the engine power of about 10% balancing the power requirement using MCFCs with CO₂ capture. Using Aspen Plus each solution was investigated. The analysis contemplated LNG steam reforming to produce the H₂ necessary for cell operation and the separation and liquefaction of CO₂. Two case studies were considered comparing existing passenger ships with engines working on HFO and on LNG respectively. Although both solutions showed potential for the reduction of CO₂ emissions respecting the IMO regulations, the SOFC solution requires a major change in the design of the ship, while MCFCs are proposed as an urgent solution allowing ship retrofitting without demanding update.