Sustainable shipping on the horizon: Environmental requirements and institutional pressures in maritime decarbonisation

Reduction of greenhouse gas (GHG) emissions in the maritime sector is progressing slowly but can be accelerated through a combination of environmental requirements and institutional pressures from authorities and companies in the transport industry. Progress was explored in an interview study involving 17 transport-purchasing companies, shipping companies and ports in northern Sweden with a strong sustainability focus. The study identifies eight environmental requirements (e.g. access to alternative fuels and electrification of equipment) and maps them to five institutional pressure types (coercive, normative, mimetic, instrumental and relational), revealing how pressures translate into operational demands and where misalignments slow implementation. Coercive pressures , in terms of regulations, were seen as essential to driving sustainable shipping, while softer pressures, particularly relational , were most commonly used. Although clear driving forces for climate transition in shipping exist, high costs associated with new technologies and alternative fuels remain a significant barrier. Voluntary initiatives contribute but seem insufficient alone to achieve shipping's climate goals. • Sustainability focus in production is not yet fully reflected in transport. • Regulations are key to climate transition of shipping, to complement voluntary initiatives. • Coercive and instrumental pressures remain weak but are highly anticipated. • Relational pressures are central as companies seek value-aligned partners. • Institutional pressures interrelate and are capable of reinforcing each other.