20 years of experience, 32 installations, 150 mio savings: MMT is a key player in using Waste Heat Recovery for savings.

To put it simply, a waste heat recovery system uses the heat from the main engine exhaust gases. This heat energy is used for generating steam that is channeled to the turbo generator where the power for the vessel is produced. In other words: The WHR helps to generate more power on the vessel without using more fuel.

Since the 1980s WHR-systems have been installed on 32 APMM-container vessels and they demonstrated an energy and fuel consumption reduction of 9%. “It is the largest known CO2 reduction mean” says Ole Graa Jakobsen, who was project manager when the first system was installed on a vessel of APMM in 1988. Until now, the company saved around 150 mio by using waste heat recovery.

No success without challenges
The waste heat recovery system is only in full operation above a certain engine load limit. In 2009 however a common slow steaming policy was introduced, meaning engines should operate at low load in order to save fuel and CO2 . “We had to find ways to optimize the output of waste heat recovery at low load” explains Ole. His team therefore worked on a dual-speed strategy, where vessels with WHR operate either at high speed 21 knots or below 17 knots. “Our experiences show that vessels with WHR still get more efficiency than standard designed vessels, even at low load” Ole says.

On all large container vessels ordered since 2008, WHR will be installed. MMT has used the gained knowledge to improve the design of these new buildings and optimize the overall fuel savings to more than 22%! But this is another story…