Source: Carbon Positive
Despite ship operators’ slow uptake of exhaust scrubbers in the face of growing sulphur, carbon and nitrogen emission limits, some are predicting a big maritime role for the technology in coming years.
Scrubbing units applied to the exhaust stacks of ships and land-based emitting installations remove, to varying efficiencies, the toxic and climate-changing pollutant gases that are increasingly the focus of environmental regulation. While the technology is proven in the case of cleaning sulphur and nitrous oxides, SOx and NOx, the jury is still out on claims of breakthroughs in carbon dioxide (CO2) scrubbing.
However, in the next few years, it will be a significant tightening of global, regional and local-authority rules on sulphur emissions at sea and in port that will drive any uptake of scrubbers. For the moment, the high upfront cost of installing them, especially retrofitting to old vessels, is proving a major barrier. There is also environmental pressure from some quarters on operators to pursue cleaner fuel options rather than persisting with dirty fuel and scrubbing it. There is a vague threat the EU will ban heavy bunker fuel entirely in its waters.
But significant doubts over whether fuel refiners can produce enough low-sulphur fuel to meet the needs of the international shipping fleet in coming years means that alternatives such as switching to liquid natural gas (LNG) or installing SOx scrubbers are under increasing consideration. The best scrubbing technologies appear able to remove up to 98 per cent of sulphur content from marine exhaust emissions.
In 2012, the global limit on marine fuel sulphur content will reduce from 4.5 to 3.5 per cent, a limit that a good proportion of current bunker fuel supplies wouldn’t meet. Sometime between 2020 and 2025 the limit is to come down to just 0.5 per cent. Already, in the designated emission control areas (ECAs) of the Baltic Sea, North Sea and along the North American coastline, the sulphur limit has dropped to 1 per cent. By 2015, it is due to be cut to just 0.1 per cent, which would appear to rule out anything but LNG and marine gas oil (MGO), if scrubbing is not applied. The short-sea lines operating mostly or entirely within the ECAs face the biggest regulatory challenge. In ports, meanwhile, an increasing number of port authorities and shipping associations are imposing or agreeing to very low sulphur limits on vessels while at port.
There is growing expectation that a big shift to LNG-powered ships will take place over the next decade as more and more newer vessels are built to take advantage of the plentiful supplies of the relatively clean fuel. But 2015 will come too soon for LNG conversion for most operators.
The Exhaust Gas Cleaning Systems Association (EGCSA) which represents the scrubber makers, maintains that despite the costs of the technology, it is easier to go that route than switch to LNG. And using highly refined MGO will come with its own heavy cost impacts. The price premium that operators will have to pay for low-sulphur distillate fuel to meet the stricter limits will be from $225 to $850 per tonne, depending on the oil price, Dr Rudy Kassinger, a senior consultant at DNV Petroleum Services (DNVPS), predicts.
Don Gregory, director of EGCSA, told a Lloyds List audience this month that 5,000 to 10,000 ships could be fitted with scrubbers by 2015 when the stringent ECA limit takes effect. Meanwhile, the FUJCON bunkering conference this month heard predictions that ship owners will spend more than $10 billion on scrubbers over the next 20 years. The forecast comes from an upcoming report by Marine and Energy Consulting Limited and EMC.
The right solution for ship operators in meeting new sulphur limits will vary across different fleets, vessel classes and routes plied. A new guide from the US aims to help operators assess the scrubbing option against alternatives. With the 2015 ECA limits in mind, the Ship Operations Cooperative Program (SOCP) has released a study comparing use of scrubbing technologies and heavy fuels to the use of distillate fuels. SOCP says the guide will help ship operators assess emissions requirements, compare costs, and understand the integration and operational challenges of scrubber installation.
