C for Cold ironing

If you’ve ever happened to stay in a port area while on holidays in a seaside town, or even simply passed close by one, you’re sure to have noticed that the noise of cruise ships, ferries and container ships can be quite unbearable. Well, that’s just one small aspect of the environmental damage caused by vessels, particularly larger ones, to the places where they dock: even when moored, they are responsible for as much as 20% of the pollution in port cities, over and above the noise pollution. This figure, by no means a trivial one, has been reported by the "Transport and Environment Reporting Mechanism – TERM" scientific study from the European Environment Agency. In fact, ships actually leave their engines running even docked in harbour. This is particularly true of cruise ships, which are nothing short of floating tourist resorts carrying thousands of passengers. They are so energy intensive that, according to the estimates given in the 2023 Development Plan for Terna, the company that manages the Italian national electricity transmission grid, it would take 25 mid-sized cars a year to emit the same quantity of CO₂ that a cruise ship in port produces in just 10 hours. However, the energy transition has a solution to this problem too: it’s called “cold ironing”, a term which is not widely known among the public, but which essentially means electrifying port infrastructure in order to gradually phase out fossil fuels. This would make it possible to supply ships with power from shore, using electricity. The project is part of the process of decarbonisation in the transport sector, specifically maritime transport in this case.

Green port projects have already been put into practice all over the world, particularly in the USA and Northern Europe — in Los Angeles, San Francisco, Gothenburg and Rotterdam, among others. And Italy, whose natural geography makes the sea one of its greatest advantages in every field from trade to tourism, is not about to be left behind. In fact, cold ironing has already been included and planned for in the National Recovery and Resilience Plan (NRRP), with a considerable investment: 700 million euros between now and 2026 to co-finance efforts to include around fifty Italian ports in the Trans-European Transport Network (TEN-T), and to bring them in line with the climate goals established at national and European level. And that’s not all: the European Commission recently gave the green light to a 570 million euros package of state aid from the Italian government, running until 2033, to incentivise ships to use energy from shore-side electricity grids while they are at berth in ports, wherever and whenever possible.

Terna, which develops and manages the high and extra-high-voltage grid, is also involved in the initiative; to date (August 2024), it has already received 25 requests from 16 port authorities all over Italy, both North and South. The projects have been launched, and work is underway to achieve the targets that have been set in accordance with the deadlines and time frames necessary for the construction of new infrastructure, whether high or extra-high-voltage, bearing in mind the time needed to procure materials. There are numerous parties involved in the activities: Terna, as already mentioned, and the distribution companies for connection to the grid and related activities, in addition to the port authorities.

It’s worth remembering that the connection of an electricity plant to the National Transmission Grid (NTG) takes place following a process defined and governed by ARERA, the Italian Regulatory Authority for Energy, Networks and the Environment. Terna is obliged to provide a connection solution for all parties that make such a request; in particular, it is responsible for high and extra-high-voltage connections, i.e. the connection of plants with a power of 10 MW or higher. The connection request is the first step in a process that ends with creation of the plant and connection to the grid. In terms of cold ironing specifically, it is to all intents and purposes a request for connection to the grid from a user (in this case, the port authority), and must therefore follow the usual procedure in place for consumption users.

In Italy, the electrification of port sites is currently limited to powering some ship repair terminals and cranes used for moving goods around. However, things are starting to change: all the parties involved are assessing the best solutions for electrifying ports, at least partially, in order to comply with the contents of the 2026 NRRP. Considering that a cruise ship berthed in the port absorbs 10 MW of electricity at its peak, and that multiple cruise ships are typically berthed at the same time in the main Italian ports, electrifying their consumption may result in an electricity demand in excess of 50 MW. For this reason, it will be necessary to build high-voltage electrical infrastructure, or to strengthen the existing infrastructure, in order to guarantee that these needs will be satisfied to a high standard of quality, reliability and safety. Under these circumstances, it will be vitally important that there should be coordination between Terna, the local distributors and the Port System Authorities to ensure integrated, well organised planning of the grid works necessary, so that these can be carried out in the shortest time possible, in line with the energy and climate targets set for decarbonisation.

Over the years, Terna has already carried out preliminary analyses for at least 40 Italian ports for the 25 requests for connection to the NTG, including in synergy with distributors. The most suitable points for connection to the public grid have been identified, as well as any infrastructural adaptations needed in the national transmission grid in order to guarantee that the electricity demand will be satisfied. In terms of possible infrastructural solutions, for example, it may be necessary to adapt an electrical substation or build a new one, to build a new high-voltage line, or to adapt a cabin in collaboration with the local distributor. This will be ascertained on a case-by-case basis.

The more renewable the energy produced and consumed, the greater the benefits of cold ironing: according to Terna’s data, production from renewable sources overtook production from fossil sources for the first time during the first six months of 2024; while around 37% of Italy’s annual electricity demand was satisfied with clean energy in 2023. But this proportion must increase going forward: to meet the targets of “Fit for 55”, clean energy must cover at least 65% of final consumption in the electricity sector by 2030, thanks to over 70 GW of additional power, particularly wind and solar. Much will also depend on the strategic capability of the port authorities to provide infrastructure capable of producing green energy where required, such as solar panels or wind power plants to be located close to the ports or the areas affected.

In any case, simply switching from fossil fuels to electricity will have a significant impact. Just think, for example, of the fact that maritime transport uses fuels with a high sulphur content, which contribute to atmospheric pollution in the form of both carbon dioxide and sulphur dioxide (SO₂) and particulate matter (PM 10, PM 2.5). Scientific studies have shown that sulphur dioxide emitted into the atmosphere causes significant damage to sensitive ecosystems and reduces biodiversity and the value of the land, with negative impacts on crops and forest growth. And that’s not all: acid rain also has adverse effects on the cultural and architectural heritage of cities, with the potential to damage buildings and monuments. That’s not to mention the harmful impacts of pollution caused by sulphur dioxide on human health, particularly for those of the population who suffer from respiratory diseases. All of this, just to keep ships berthed in the ports for a few hours: this is why cold ironing is such a vital step in the energy transition.