The first of three ethane-fuelled engines has been delivered for a trio of ships on order for Germany’s Hartmann Reederei on order at China’s Sinopacific Shipbuilding. They will be pioneers for ethane fuelling, believes René Sejer Laursen, promotion manager at MAN Diesel & Turbo.
The ships will each carry 35,000m3 of the gas so have an obvious source of fuel, but Mr Laursen has a bigger vision: “we see potential for all ships to use ethane gas in the future,” he said during a presentation about the company’s multi-fuel engines during the Danish Maritime Days in October.
Ethane is a by-product of shale gas production, he pointed out, with up to 20 per cent of shale gas being ethane. So in the US, ethane is relatively simple to obtain and he conceded in conversation with Marine Propulsion that availability elsewhere is not good. But shale gas extraction is being explored in other parts of the world and Mr Laursen expects it to become a significant fuel option elsewhere.
Engines must be specifically designed to burn ethane, which has different characteristics from other fuel gases and MAN Diesel & Turbo uses the ME-GI-E designation to identify those engines. The Hartmann vessels will each be fitted with a Tier-II 7G50ME-GI-E engine.
Meanwhile, Dalian Shipyard holds orders for five 35,000m3 ethane carriers, which will each be fitted with a 6G60ME-C9.5-GI-E engine, coupled with an EGR system to bring it up to Tier III emission standards. These engines will also burn LNG so shipowners can choose whichever fuel is the most cost effective where they are operating, Mr Laursen said.
MAN Diesel & Turbo is also looking at cost-effective fuel gas supply systems and has developed a prototype pump and vaporiser unit. Other devices are available but “we have organised it in a simple manner and removed many sensors, valves and pipes and reduced the size of it,” Mr Laursen told Marine Propulsion. It is also designed for redundancy, he said. It has three piston pumps for pressurising the gas but only two are needed, so the third is ready to start if one of the others fails.