by Diego Gavagnin

Only a few days left to the sulfur content limits in marine fuels worldwide, as per the decision of the IMO, the International Maritime Organization, the UN agency that governs maritime traffic and its impact on 'environment.

The goal of the intervention is not so much the preservation of climatic stability as the pollution of the atmosphere with the health consequences on the populations of the port and coastal cities. In the background the certainty that the most direct consequence of the globalization of the economy would have been the increase in maritime traffic, as happened.

From 1 January it will no longer be possible, in all the seas of the world, even offshore, to use fuels with a sulfur content greater than 0.5% compared to the current 3.5%. This decision, also endorsed by the European Union, is effective from January 1, 2015.

Thus, shipowners, fuel producers and public administrations have had 5 years to prepare. Yet the only certainty of how the market will settle seems to be uncertainty. Three choices are available: the use of 0.5% marine diesel; the application to ships of filters and washing of emissions, continuing to use "heavy" oil fuels; the LNG.

A few days after the "big bang" there is no idea what the price of 0.5 diesel will be, but the greater uncertainty concerns the availability of traditional fuels: each engine requires a specific quality, the use of different can block the engine.

On chimney filters a fundamental detail: they are of two types: "open cycle", less expensive, which washes and solidifies sulfur, carbon black and other pollutant (even climate-changing) emissions and discharges everything into the sea; closed-loop, with collection of these products and their delivery to ports. Great uncertainty on the cost of disposal in landfills, to which the port authorities must provide, as they are "special" waste.

Finally, LNG, considered the best and most "definitive" solution, because it acts both on pollution and on climate change (provided that it does not release methane, but it is a technical, feasible issue). Many advantages but high costs, even if there are prospects for future economies of scale. The cryogenic tanks (the LNG is such at minus 162 degrees) are larger and heavier than the traditional ones, occupy more space, which means less containers and passengers.

After a couple of years of doubt, the choice for the least expensive solution prevailed: open-cycle filters ("open loop scrubber", the technical term in use). The problem is that in recent months, with unexplained delay, port authorities around the world have begun to prohibit entry to ships or the use of these filters in their waters. If they had sounded the alarm in time, the owners could have made different choices.

Malaysia's most recent decision, which has banned all 12 miles of its territorial waters from entering, but also China is oriented in this direction. Meanwhile, the use of open-cycle scrubbers in ports is prohibited, as well as in California. Attend the position of the European Commission. Ban in the ports of Belgium, Ireland, the Norwegian Fjords, Dublin and Waterford in Ireland, in the Rhine in Germany, in the six main French ports, in Gibilterrra, in the four main cities of Portugal, in Primorsk and St. Petersburg in the Russian Federation so in other tens, including Ravenna.

There are two reasons for these decisions. For the port authorities it is above all the contamination of the seabed, with the consequent problem of dredging. Sediments become special waste, especially where the seabed is lower. For the national authorities, it counts the acidification of the water (sulfur does not fall from above but is placed directly into the sea, concentrated) which reduces the sea's capacity to absorb CO2.

Someone has done something wrong. Meanwhile, however, shipowners have spent millions of dollars to put open-loop filters and it seems prohibitive to go back. A serious mistake was probably to separate the decisions on pollution from those on the climate, adopted by the IMO only recently. The goal is to reduce CO2 emissions by 50% by 2050 compared to 2008. It seems like a long time, but it is not thinking about the life cycle of the ships. If this decision had been adopted in 2015, the choice of LNG would have been wider (as was expected at the time).

Today there are over 3700 ships with open-cycle filters, about 70 with closed-cycle scrubbers, 150 with LNG and another 150 under construction and in order (but LNG ships are the largest, with the largest consumption); all the others will use diesel oil, a petroleum derivative.

For the dissemination of maritime LNG the biggest problem remains the uncertainty on logistics and simplicity of supply. For example in Italy it is not possible due to lack of rules, while LNG is usually loaded for 10 years in the North Sea and in the Baltic and for some years regularly in Spanish ports (from tankers and tankers).

In Sardinia the new flagship of the Costa Group is about to arrive, with over 6,000 passengers, which in honor of the island is called Costa Smeralda and will use LNG. He will not be able to refuel in Sardinian ports, as in all other ports, despite Italy's main Mediterranean cruise target.

Despite all these uncertainties, the Annual Energy Outlook of the International Energy Agency predicts an increase of 5,000 per cent of LNG ships by 2040, which means around 7,500 compared to 150 today. Can maritime LNG reach these figures in the next twenty years? Probably yes, considering that methane, now fossil, can be replaced with biomethane and synthetic gas, obtained by mixing hydrogen and CO2, removed from the environment.