Powering the Future: A 30-Year Roadmap to Zero-Emission Port Operations

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Last Updated on: 14th May 2025, 10:29 pm

European ports face an increasingly urgent mandate to reduce carbon emissions across their landside and waterside operations, driven not only by climate policies but also by local air quality concerns. The scale of the challenge is enormous yet manageable, provided clear strategies and timelines are established.

My perspective is straightforward. All of the ground vehicles and equipment will electrify. All of the port vessels will electrify. All of the inland shipping will electrify. Almost all of the short sea shipping will electrify. Longer distance shipping will be battery-electric hybrid, operating in national waters and ports on battery power, connected to shore power when hoteling and usually leveraging containerized batteries that are charged in the container terminal rather than entirely on built in batteries.

This series is triggered by a bunch of people asking me if the same pattern my co-author Rish Ghatikar and I used for road freight shipping in the USA would apply, with buffering batteries and as much solar as could be placed on rooftops, solar canopies and nearby fields as possible. The answer is yes, with variations.

I’ve covered all of this ground before, but it’s time to lay out a scenario for a mid sized port as an example, in part because it’s interesting to see how it might play out. I’ve done this before for aviation, using Edmonton Airport’s 120 MW of solar and articulating a multi-part strategic build out of airport and aviation electrification. I’ve covered port ground vehicle electrification as well, having spent time with Sahar Rashibeigi, head of port decarbonization for Maerk’s APM Terminals division. My projection of maritime shipping decarbonization through 2100 leans heavily on battery electric soaking up a lot of the energy requirements on the water, with the rest provided by biofuels. But a projection through a few decades of port and shipping electrification for a port is an interesting exercise, at least to me.

To better illustrate what an ambitious yet achievable decarbonization trajectory looks like, it’s useful to examine a mid-sized European port, comparable in size and function to Amsterdam or Ghent. Such a port typically handles around 75 million tonnes of cargo annually, encompassing containers, bulk commodities, and Ro-Ro (roll on, roll off) cargo. Its traffic is notably diverse, characterized by roughly 5,500 seagoing vessel calls per year, in addition to thousands of inland barge movements through connected river and canal networks. This variety—spanning inland barges, short-sea vessels like feeder container ships and Ro-Ro ferries, and large blue-water vessels including deep-sea container ships and bulk carriers—is precisely what makes such a port representative of many medium-sized European maritime hubs, making it an ideal candidate for exploring decarbonization pathways.

To understand how profound a shift decarbonization represents, it’s essential to clearly outline the port’s current state. Present-day port operations remain heavily reliant on diesel-powered equipment and vehicles, both within the container yards and across cargo handling activities. The typical fleet might include around 20 diesel-powered straddle carriers or rubber-tire gantry cranes, essential for container movements within the terminal. Each of these machines consumes roughly 19 liters of diesel per hour, a figure exemplified by operational data from Hamburg’s extensive container facilities. Alongside these are approximately 50 diesel terminal tractors, tasked with shifting containers around the yard. Mobile harbor cranes, reach stackers, and forklifts similarly operate primarily on diesel, handling general and breakbulk cargo efficiently, but contributing significantly to local air pollution and carbon emissions. Beyond the port authority’s own vehicles, thousands of external heavy-duty trucks arrive daily to pick up or deliver cargo, their emissions compounding local environmental impacts.

The port’s harbor craft fleet, although small, has a disproportionately large emissions footprint. Typically, there would be around three harbor tugs, essential for safely maneuvering larger vessels in and out of berths. Each tug, rated between 60 to 70 tonnes of bollard pull, annually burns roughly 150 tonnes of marine diesel oil, translating into about 1.75 GWh of energy per vessel per year. Smaller harbor vessels—pilot boats, mooring tenders, and maintenance craft—also rely predominantly on diesel. In addition, there’s usually at least one frequent ferry service operating short routes, perhaps to a nearby coastal city, consuming on the order of one to two million liters of marine diesel per year, equivalent to approximately 10 to 20 GWh of energy annually. These harbor craft, constantly moving and essential to daily operations, are prime candidates for early electrification or alternative zero-emission propulsion technologies due to their predictable and relatively short operational cycles.

Significant emissions at ports also arise from vessels docked at berth. Currently, visiting ships typically run diesel auxiliary engines continuously to generate electricity onboard, required for systems such as lighting, cooling containers, and maintaining crew living quarters. For context, a typical large container ship at berth consumes about two to four tonnes of fuel per day, equivalent to approximately four to eight megawatt-hours of electrical energy if sourced from clean shore-side power. Across a representative mid-sized port, total annual auxiliary fuel usage from all visiting ships may amount to around 2,500 tonnes of diesel, equating roughly to 10 GWh per year of power generation that could otherwise be supplied by shore-side electricity. Additionally, bunker fuel deliveries at such a port total around half a million tonnes per year, mostly heavy fuel oil, which underscores the considerable indirect emissions associated with maritime trade facilitated by port operations.

The port’s own direct electricity consumption today remains relatively modest, typically ranging from 10 to 20 GWh annually. This energy supports activities like offices, existing electric cranes, refrigerated container plugs (reefers), and area lighting. Some forward-looking ports in Europe are already meeting 15–20% of their electricity needs through rooftop or canopy solar installations, pointing to an existing but limited adoption of renewables that will need significant expansion as decarbonization progresses. Indeed, future electrification of port vehicles, harbor vessels, and visiting ships through extensive shore power systems will substantially increase overall electricity demand, demanding careful strategic planning and investment in new renewable capacity and grid infrastructure.

For the purposes of the series, I decide a Sankey diagram of energy flows in GWh consumed annually would be a useful representation. As always with fossil-heavy energy flows, the rejected energy outweighs the useful energy services substantially. It would be a lot worse if port cranes, buildings and a lot of other equipment weren’t electrified already. I’ll be updating these energy flows for each increment to show how energy requirements diminish, and adding wind and solar inputs. As a note, I did one including bunker fuel for oceanic ship journeys, and unsurprisingly that energy flow dwarfed the rest of them. This Sankey does not include full bunkering, just port consumption for auxiliary power.

Collectively, these current activities result in annual carbon dioxide emissions ranging between 200,000 and 300,000 tonnes for a port of this scale, a figure comprising emissions from diesel vehicles, harbor vessels, and auxiliary power generation from docked ships. This substantial baseline of emissions presents both a challenge and an opportunity. Eliminating these emissions entirely, while ambitious, is achievable through a carefully phased strategy combining electrification, shore-side power, advanced battery storage systems, and substantial integration of renewable energy sources like offshore wind and solar power.

The complexity of the port’s current operations, combined with the high energy density required by heavy equipment and ships, makes clear that incremental and carefully planned steps will be essential. Each stage of the journey must balance investment in infrastructure and technology with proven solutions, economic viability, and operational continuity, ensuring the port maintains competitiveness while steadily progressing towards full decarbonization over the coming decades. Subsequent articles will deal with five year increments, building out the transformation through time.