Green Corridor bulker design heralds sustainable future
The Naval Architect: September 2017
Since the unveiling of the LNG-fuelled ‘Newcastlemax’ bulk carrier design at Nor-Shipping back in June, ‘Green Corridor’ has generated a lot of interest. The Joint Industry Project (JIP) includes stakeholders from all stages of the supply chain, each with a vested interest in the venture. This particular route between Australia and China was chosen because of the involvement of three of Australia’s largest cargo owners in the project: BHP, Fortescue Metals Group Ltd (FMG) and RioTinto. Woodside, the Australian-owned LNG supplier, is also a key partner, as with LNG bunkering availability still an issue, Woodside has a large amount of gas available in Australia it can put at the disposal of this trade route. Shipowners MOL and U-Ming Marine, ship designer Shanghai Merchant Ship Design & Research Institute (SDARI) and classification society DNV GL, which is acting as project manager, make up the rest of the partnership. The main intention of the JIP is to design an LNG-fuelled bulk carrier that will be used to transport mainly iron ore, but also with the capacity to transport coal, between Australia and China, with bunkering taking place in Australia.
The 300m long, 210,000dwt dual-fuel Newcastlemax has been developed by Chinese ship designer SDARI and takes inspiration from their Green Dolphin design, which was first launched in collaboration with DNV GL in 2013. Morten Løvstad, business director bulk carriers at DNV GL – Marine, revealed that SDARI was chosen not only for its expertise, but also so that the final design would be readily available to numerous shipyards: “They were invited at quite an early stage and we are very pleased to have SDARI onboard. We wanted the design to be less proprietary, so by selecting SDARI we get a design which many shipyards can build according to.”
Chen Gang, technical manager, SDARI, also speaks of the two companies’ well-established working relationship: “SDARI has collaborated with DNV GL on various projects for a long time, such as Green Dolphin 38 & 575, and SDARI’s Dolphin and Green Dolphin series bulk carrier designs have dominated a large share of the bulk carrier sector since 2000. To be involved in this project means SDARI can bring the best experience and know-how to the Green Corridor project.”
Perhaps the most talked-about aspect of the design is the placement of the two 3,000m3 Type C LNG fuel tanks. Several different locations were considered before settling on the proposed placement, which will see the tanks on the main deck, below the accommodation quarters but slightly submerged into the engine room to make use of the extra unused height, therefore not jeopardising any extra capacity for cargo elsewhere on the vessel. Other locations that were considered included mid-ship inside the cargo holders and in front of the engine room.
Placing the tanks so close to the engine room reduces the cost of the cryogenic pipes and diminishes the risk of there being any drop in pressure, compared with if the tanks were placed mid-ship. However, with every design component, there are some issues to work around. For instance, the fuel tanks’ placement means that due to the large weight in the aft of the ship, it will experience a very high bending moment, which will need to be compensated for by adding more steel to the hull structure, explains Løvstad. It was also imperative that the placement of the tanks complied with various safety regulations: “The fuel tanks would be surrounded by the steel structure and A-60 insulation, and of course completely separated from the accommodation area and cabins. This design ensures compliance with the IGF Code, including the requirements for fire safety, enclosed spaces around the fuel gas system and full protection from operational impact,” continues Løvstad.
At the initial briefing at Nor-Shipping, Løvstad explained the project’s aim was to create a design that was more evolutionary than revolutionary, so that the vessel could become a reality as soon as possible. The project partners are hopeful of orders being placed before the end of the year and have set a predicted vessel completion date of 2020, just in time for the sulphur cap enforcement.
Other technologies were considered, such as lightweight composite materials, but didn’t make it into the final design. Scrubbers were also considered during the design process: “We did look into scrubbers but we fairly quickly decided that this technology would not meet all the strict environmental regulations that we wanted to comply with. It only addresses the sulphur cap, it doesn’t address particulate matter, it doesn’t address CO2 and it doesn’t address NOx, so that ruled out scrubbers as an option.”
Retrofit options were also contemplated, and a design suitable to be installed in existing vessels was submitted by MOL. It was established that retrofitting would be possible, but the project partners decided to progress with a new build design as it was significantly less expensive. Løvstad argues that a cheap source of LNG would be required to justify such an investment: “There are some challenges from a structural point of view and from a stability point of view. So a retrofit would be possible, but may not be the most attractive or realistic solution, at least in the short term.”
Green credentials vs. business sense
One of the challenges with the Green Corridor project was to present a design that is not only environmentally conscious and compliant with the IMO’s upcoming regulations, but that will also be attractive from a business perspective, so that cargo owners and shipowners will be encouraged to opt for the design not simply to fulfil their ethical and legal obligations, but because it also makes sound financial sense.
As the production of LNG continues to rise, so does its popularity. According to DNV GL, using LNG as fuel reduces SOx emissions by 100% — good news for the 2020 0.5% sulphur cap — and NOx emissions by 85% in low pressure engines, as well as significant reductions in CO2. It also almost eliminates particulate matter. Responding to those detractors who argue the fuel isn’t environmentally-friendly enough, Løvstad says that LNG is “the greenest option that we have for the ship segment, at least with respect to emissions to air”.
Mike Utsler, Woodside’s chief operations officer, also finds it to be a financially viable option: “We looked at a wide range of capital and operational costs, including LNG and low sulphur fuel oil price sensitivities, as well as conducting a high-level bunker supply chain assessment. Based on this, we found that under the most realistic scenario, the payback period for the design was under 10 years, and under the optimistic projection just 6.7 years.”
With optimisation comes increased efficiency for the vessel’s particular use, but also a restriction in the possible use for other routes or applications. Løvstad explains that while the Green Corridor design will be optimised for the Australia – China route, the JIP partners have also been conscious to provide some flexibility for potential employment on other routes: “We did build in a higher LNG capacity to be able to trade on different routes, since a capesize vessel could potentially operate on other trading routes as well, and unlike an ore carrier, the capesize could also carry coal and potentially even grain. Therefore, our design has spare capacity beyond what will be needed for the trade route between Australia and China.” However, he points out that the ongoing difficulty of limited LNG bunkering infrastructure means the use of the proposed vessel on other trade routes would have to address the same refuelling challenges.
Chen Gang also adds that vessel designs optimised for particular trade routes could be the future for large carriers: “For small bulk carriers like Handymax, the design should take into consideration that the ship may need to transport various bulk cargo all over the world. It is, therefore , not practical to define a particular trade route. For big carriers like Green Corridor 210K however, the cargo transported is major bulk, like iron ore and coal, so a particular trade route makes sense.”
As The Naval Architect went to press, plans were in place for all partners to meet in Singapore at the end of August to discuss and finalise the results of this initial stage. Green Corridor is also turning its thoughts towards the development of a Very Large Ore Carrier (VLOC), as Løvstad continues:“There’s fierce competition between Australia and Brazil on the iron ore export, so some of the miners would like even more optimisation to lower the costs of the transportation of iron ore in particular.
“With a dedicated ore carrier you have more flexibility to choose the best location for the LNG fuel tanks because you’re not so concerned about losing volume capacity from the cargo, and because it’s heavy cargo, you usually don’t fill up the cargo tanks to the maximum anyway. This means you can utilise some space for the fuel tanks inside the cargo area. On a capesize you also want to have the flexibility to transport coal and grain, where volume is critical, and because that is a lighter cargo you will fill up the cargo holds to the maximum. So that was mainly the reason why we placed those LNG fuel tanks on the deck beneath the accommodation area on the capesize vessel design.”
DNV GL is still optimistic that the project is on track to be taking orders for the vessel before the end of the year and discussions are currently taking place between owners and charters and yards. With environmental considerations becoming ever more integral to vessel design, perhaps Green Corridor could be the project to prove that environmentally-friendly shipping can go hand-in-hand with good business acumen.