Swiss marine power company WinGD has completed shop tests of its groundbreaking variable compression ratio (VCR) technology. The results confirm that methane reductions from new X-DF engines with VCR technology deliver similar ship greenhouse gas (GHG) emissions to high-pressure dual-fuel technologies, while delivering a total system cost and fuel cost advantage for several vessel applications.
The VCR shop test was completed at Mitsui E&S DU (MESDU) facilities in Japan, where the first X-DF2.0 engines with VCR are being built for bulk carriers owned by NYK Lines. The six-cylinder, 62-bore engine achieved around 30% fewer methane emissions than the same engine without VCR, taking total slip to around 0.83% of gas consumption. This is less than half the EU (and provisional IMO) default slip attributed to low-pressure, low-speed dual-fuel engines in maritime regulations. The reduction is expected to be even greater for engines with a larger bore.
WinGD Vice President Product Centre, Peter Krähenbühl, said: “Over the past decade we’ve worked to ensure that the unmatched reliability and low capital expenditure of X-DF engines are supported by the lowest possible overall GHG emissions. The fuel consumption and methane slip reductions achieved by VCR bring us to that point. Low GHG emissions will be fundamental for shipowners as carbon pricing measures take effect, which is why we have already seen strong uptake, with well over 100 new X-DF engines ordered with VCR so far.”
The significant reduction in methane slip was achieved alongside a fuel reduction of up to 5.8% in gas mode and up to 6.9% in diesel mode. The charts below show how those improvements affect the fuel cost and CO2 equivalent emissions compared to previous X-DF engine technologies and a high-pressure engine counterpart, for a typical car carrier operating profile.
