Algeciras, Barcelona and Valencia stand out as popular destinations for tourism and as notable sources of emissions among European ports. Spain ranks as the second most polluting country in the region when port activities are considered, with approximately 14 million tonnes of carbon released annually according to the latest research from the Transport and Environment (T&E). In recent years, sustainable options have emerged for maritime transport, including ammonia, which remains mostly in the research phase, and dock electrification, seen as the most viable near-term solution. The European Commission is advocating for the Onshore Power Supply (OPS) system, a technology that lets docked ships tap into the electrical grid, power down their engines, and cut CO2 emissions. While port authorities have begun installing OPS, experts worry about timing due to the need for new, ship-specific electrical infrastructure and grid upgrades.
The estimated investment to electrify port terminals sits around 500 million euros to meet European targets, though costs vary by location. “Some ports face power outages near the facilities, which raises the expense,” notes Sara Blanco, an analyst at maritime consultancy OCP. For example, Barcelona plans to invest 110 million dollars in the Nexigen project for this initiative, a further 90 million for OPS installation, and the remainder for network distribution, including two substations and the medium voltage network within the site. Valencia plans an initial 11 million dollars to electrify the MSC pier. The electrical connection to ships requires a total power of 800 to 1,000 megawatts (MW), while the entire state port system needs about 200 MW. Achieving this involves installing a new high-voltage interconnection near the dock, and either building a substation or sourcing it outside the port to suit power needs, explains Raúl Villa, a marine engineering doctor from the University of A Coruña and a Merchant Navy captain.
Optimism surrounds the possibility of dock electrification before 2030, provided careful planning and timely approvals. Yet doubts persist among experts. “It seems challenging to reach the goal,” says Villa. “Certain permits will be necessary to build missing port infrastructure, and when energy is insufficient, external sourcing may be required, such as routing a pipeline through city centers,” adds Blanco. Some ports, like Tenerife and the Balearic Islands, are investing in OPS, while others, including Cádiz, have struck private-sector agreements (Endesa in Cádiz). However, not all port areas have the capital needed to secure external support.
Ships and renewable resources
The European directive promoting port electrification targets the most polluting vessels, such as ferries, cruise ships, and frequent-container ships. These vessels could reduce emissions in port areas by up to 60%, potentially cutting between half a million and one million tonnes of CO2. The power needs, however, are not uniform. “A cruise terminal can require three to four times more power than a standard terminal,” states Puertos del Estado. Container docks typically demand power similar to ferry terminals; the actual consumption depends on vessel size and container throughput.
Shipping companies also bear responsibility for adapting ships to OPS compatibility. “The fleet’s typical lifespan is around 20 years, and many existing ships have not been retrofitted to meet new regulations,” Blanco points out. Currently, only a small share of the Spanish fleet can utilize OPS, according to maritime consultants. Cruise ships show the highest readiness, with about 50–60% prepared to connect to port power grids, followed by container ships. Ferries in Spain are notably less prepared, which is concerning given the high number of port calls in Algeciras and Barcelona in recent years.
Another crucial element in decarbonizing ports involves using renewable energy to connect ships. “If the renewable input grows, OPS becomes more feasible,” according to Puertos del Estado, though this adds budgetary pressure. Three options exist: producing energy inside the port is challenging due to limited space; utilizing excess energy from the national mix; or securing a Power Purchase Agreement (PPA) with a producer of solar or wind energy. Any such agreement must comply with the Public Contracts Act. Other obstacles include the desire to allocate the produced renewable energy to other uses. “Marine diesel is expected to disappear, and decarbonization should be completed by 2050, which will require renewable fuels like green hydrogen and ammonia,” Villa notes. [Sources: Port authorities and energy sector analyses]