According to ABB, classification society DNV has quantified the gains that owners of LNG carriers could expect to achieve using the new Dual Fuel, Electric+ (DFE+) solution developed by ABB and MAN Energy Solutions.
Comprising MAN’s four-stroke 49/60DF dual fuel engine and ABB’s Dynamic AC power distribution and control system, the solution has been developed to overcome efficiency challenges that are specific to the vessel type.
DNV’s Maritime Advisory assessment concluded that the DFE+ concept is “a competitive and more energy efficient alternative to even the most efficient conventional dual-fuel LNG carrier propulsion designs.” Smaller machinery space requirements could deliver “a conservative estimate” of 5% greater cargo capacity. Combined with other steps to optimise performance, the DFE+ concept could contribute to overall energy savings of 6%– 7.5% considering the ship’s increased transport work, DNV says.
From 1 January 2023 IMO has required shipowners to report vessels into the EEDI, EEXI and CII tools. This helps benchmark ships so that owners know what they must do to meet IMO targets for reducing GHG emissions.
As the newest addition to MAN’s four-stroke portfolio, the MAN 49/60DF engine is optimised for LNG. It is compatible with ABB’s Dynamic AC system, which is said to combine the merits of conventional AC with those of variable frequency to allow the engines to operate on optimal speeds – significantly improving total fuel consumption.
Prof George Dimopoulos, Scientific Advisor, DNV said: “Owners of LNG carriers face specific challenges in complying with the regulations, given their reliance on propulsion solutions with limited potential for efficiency gains. The ABB – MAN propulsion concept aims to offer a highly effective way for LNG carriers to meet progressively tightening emissions regulations while also reducing fuel costs.”
Rune Lysebo, Strategic Market Development, ABB Marine & Ports added: “With the current global orderbook for LNG carriers including more than 200 vessels, and emission regulations continuing to tighten, owners need new technologies to meet the requirements that apply to this specific class of ships. DNV’s testimony on the gains available to LNG Carriers with the new solution developed by ABB and MAN Energy Solutions proves the time is right to explore the next-generation technologies for this vessel type.”
DFE+ could be installed with an energy storage solution to operate as a spinning reserve or come coupled with ABB’s Azipod electric propulsion. ABB and MAN will explore integrating fuel cells as the technology matures.
Image: ABB dual-fuel electric propulsion system (credit ABB)