A recent study conducted by researchers at Chalmers University focused on the external costs of scrubber water discharge from ships, revealing significant environmental and economic impacts.
The Chalmers University study assessed over 3,800 vessels equipped with scrubber technology, finding that the discharge contributed to pollution in the Baltic Sea, incurring socio-economic costs exceeding EUR 680 million between 2014 and 2022. In terms of the shipowner perspective, the researchers calculated the costs of installing and maintaining the scrubber systems, as well as the monetary gain from running the scrubber-equipped vessels on the cheaper and dirtier heavy fuel oil instead of the more expensive low-sulphur fuel alternatives.
According to the calculations, the majority of the shipping companies that invested in scrubbers have already reached break even, and the total surplus by the end of 2022 for all of the 3,800 vessels, was EUR 4.7 billion. The researchers also note that more than 95 percent of the most common scrubber system (so-called open loop) are repaid within five years.
Moreover, the study highlighted the regulatory landscape surrounding scrubber discharge. Denmark recently implemented a ban on scrubber water discharge within 12 nautical miles of its coast, joining other countries like Germany, France, Portugal, Turkey, and China in imposing national bans or restrictions.
Although Sweden lacks a general ban, some ports, including the Port of Gothenburg, have independently prohibited scrubber water discharge. The researchers advocate for increased attention to this issue in the Swedish Parliament, emphasizing the opportunity to mitigate negative impacts on the marine environment.
