After already making a firm commitment to slash its greenhouse gas emissions by investing in two new LNG-powered high-speed ferries, Destination Gotland has taken things a step further by introducing BioLNG into its fuel mix. The company is already blending 10% BioLNG and has run successful tests running on 100%, accelerating compliance with its deadline to achieve a 70% reduction in carbon emissions by 2030.
Located in the Baltic Sea off Sweden’s southeast coast, the island of Gotland boasts stunning natural scenery, sandy beaches and – in its capital Visby – a UNESCO World Heritage Site. No surprise, then, that it draws tourists in huge numbers, with most of them coming from mainland Sweden.
Destination Gotland AB, owned by Rederi AB Gotland, is one of Sweden’s most well-known passenger shipping companies, operating ferry services between Visby and the harbours of Nynäshamn and Oskarshamn on the mainland. Every year the company’s vessels carry close to two million passengers, over half a million cars and almost a million cubic metres of cargo.
In its climate roadmap Destination Gotland has set itself the goal of reducing its carbon emissions by 70% by 2030 compared to 2010 levels. M/S Visborg and M/S Gotland, the company’s two gas-powered high-speed ferries, feature Wärtsilä 50DF dual-fuel engines and represent a huge step towards hitting this target. The vessels are also fitted with Wärtsilä gearboxes, controlled pitch propellers, Energopac rudders, tunnel thrusters, 20DF dual-fuel auxiliary engines and LNGPac fuel gas handling systems as well as Wärtsilä’s NACOS Platinum automation and navigation system.
“Switching to LNG had an immediate impact on our carbon emissions compared to using HFO and also virtually eliminated local emissions such as sulphur, particulates and NOx without any need for after-treatment. Since we had already invested in dual-fuel engine technology it was an easy and natural next step to introduce BioLNG into our fuel mix,” explains Mats Emanuelson, Technical Manager at Destination Gotland. “Making the switch will help us to reach our 2030 target even more quickly.”
BioLNG, recognised as a zero-emission fuel under the FuelEU Maritime initiative, is produced from feedstocks such as household and industrial waste, manure from agriculture and sewage sludge from wastewater treatment plants. The methane emitted when waste is digested is separated from the other biogas components and then liquefied, ready to be used as a fuel.
Destination Gotland runs a blend of 10% BioLNG onboard its Visborg and Gotland ferries, which represents a 10% reduction in CO2 emissions. Of course, when you consider overall well-to-wake greenhouse gas emissions it’s not quite that simple, as Mats explains: “Just as with regular LNG, with BioLNG there is the methane slip to take into account. Plus, the liquefaction process consumes a lot of energy, and while in Sweden and Norway, where we source our gas, this is done using clean energy, this may not be the case everywhere. However, despite these qualifications, we can say with confidence that adopting BioLNG is helping us to significantly reduce our carbon footprint.”
Furthermore, making the switch has not required any changes in bunkering operations or onboard equipment such as fuel storage and supply systems, nor has it had any impact on vessel operations: “In practical terms nothing has changed,” Mats says. “The engines have been operating exactly the same as with regular LNG, with no discernible differences. After we had run on a 10% blend we received a new delivery of BioLNG and decided to run on 100%, which meant the vessels’ CO2 emissions were reduced by 100%. We filled one tank onboard with BioLNG and operated purely on that for one week. The results were the same – in other words, business as usual!”
The next steps will be to gradually ramp up the volume of BioLNG, with the increments determined according to availability and, of course, price. “As things stand, in the near future there will be sufficient supply from local producers to run our two gas-powered vessels on 100% BioLNG, which is our ultimate goal. One challenge, as more companies see the benefits of the fuel, will be its price, which is likely to rise quite quickly if production can’t keep pace with demand,” Mats points out.
“The engines have been operating exactly the same as with regular LNG, with no discernible differences. After we had run on a 10% blend we received a new delivery of BioLNG and decided to run on 100%, which meant the vessels’ CO2 emissions were reduced by 100%.
- Mats Emanuelson, Technical Manager at Destination Gotland
With regulatory pressures to decarbonise increasing and several different options on the table with regard to future fuels and other emission-reduction technologies, seeing a clear path forward can be challenging.
While Destination Gotland is naturally keeping tabs on the latest developments in the market, Mats explains that the organisation is very happy with the choice it has made: “We are not ruling anything out completely of course, and have investigated other fuels like ammonia and methanol, but as we see things now BioLNG is the right choice for us. It is a clean, readily available and easy-to-use fuel that supports our decarbonisation target, and in the future it can be made even cleaner with technological developments to address the methane slip issue.
“Electrification is a hot topic today, and although we see it as playing a supporting role for current and future technologies, I am not that sure that it is the right way forward for us. BioLNG is a fuel that deserves more attention from politicians, regulators and the industry as a whole. All the so-called future fuels come with a price. Methanol for example is quite carbon intensive to produce, while ‘clean’ hydrogen is sometimes produced using BioLNG and is more challenging to handle. Why use one clean fuel to produce another when you can use the gas directly on board? From well to wake BioLNG is a very competitive fuel, which for us makes it a no brainer!”
Read more about LNG conversions at: https://www.wartsila.com/insights/article/time-to-take-another-look-at-lng-conversion