The power to change

While air pollution legislation continues to force ship owners towards lower emission strategies, sustained lower heavy fuel oil prices have caused them second thoughts on the timing of fuel selection decisions – giving a welcome shot in the arm to suppliers of the abatement technology that will support the continuing use of HFO.

Few analysts predicted the oil price collapse of late 2014, with subsequent forecasts in early 2015 seemingly based on best guessing. In looking for some insight into future trends it is therefore worth reflecting that, whatever the bunkering market looks like in terms of future fuel selection by market share, some technical advances developed with one set of cost assumptions in mind are equally capable of supporting another set.

ABB Turbocharging says its two-stage turbocharging solution Power2 enables the higher engine power density targeted for new generation diesel and dual-fuel marine engines designed to reduce fuel consumption and emissions. As engine makers have brought modified main power units to market running on diesel and liquefied natural gas, ABB Turbocharging has been a key development partner, demonstrating that Power2 has the flexibility to cater for a range of fuels in the future.

Two-stage turbocharging allows the pressure ratio to be doubled without increasing mechanical load, within a profile that is only 20% larger than state-of-the-art single-stage turbocharging solutions. The company says its latest Power2 800-M increases turbocharging efficiency beyond 75% and increases pressure ratio capabilities up to 12.

Power2 is already operational in power plant applications, and similar interest is expected in the marine industry. Offshore vessels, for example, are expected to benefit from the high engine power density the system enables, leading to low power-to-weight-and-size ratio as well as excellent transient capabilities. Uptake is also expected in the cruise and ferry market, to optimise fuel efficiency of four-stroke engines at high loads over extended periods.

Enhanced performance converts to a significant efficiency gain compared with single-stage turbocharging. ABB Turbocharging notes that, for a 10MW engine running on HFO, the annual savings would exceed US$100,000. And as new fuels enter mainstream shipping, those savings are available whatever the fuel choice – the company says it has been a key industry partner contributing to the development of new marine engine models that will be available for use as diesel or dual-fuel in the mainstream marine and offshore markets from 2015.

Paolo Tremuli, general manager, new engine technology at ABB Turbocharging explains: “Nowadays reciprocating engines are asked to cope with various emission requirements, with vessels in different operating profiles and using different fuels, while still delivering constant high performance.”

“This new generation Power2 800-M enables engines to surpass industry standards in power output, fuel savings and emission reduction. It is applicable to engines burning all marine fuel types,” adds Christoph Rofka, senior general manager – products.

The new version of Power2 is claimed to be 20% more compact than conventional two-stage solutions, and enhanced with high availability in mind. “Our new four-stroke serviceability solution allows service from the cold side without touching any connection to the engine. Access to rotating components can be accomplished without disconnection,” ABB Turbocharging notes. This allows a completely new service concept for Power2: a removable cartridge reducing downtime and increasing ease of servicing.

“We have worked on this new generation Power2 in collaboration with a major OEM, which has been pivotal in the evolution of a solution that we anticipate will have a major impact,” says Rofka. “It also responds to the very real demand from customers for turbocharger flexibility to meet operational challenges. The enhancements to ease of servicing are a crucial part of this evolution.”

Rofka adds that the new concept offers an opportunity for shipowners to examine options for turbocharging dual-fuel and gas fuel engines. ABB Turbocharging’s Valve Control Management (VCM) technology confers additional operating robustness, in line with the necessarily strong but controlled Miller timing. For engines running on LNG this is a critical attribute to ensure ‘diesel-like’ performance, says Rofka.

Formerly predicated on high bunker fuel prices, the industry’s obsession with ship efficiency has sustained, despite the recent oil price low. The consequent suspension of exploration work by many of the world’s oil majors has been reflected by falling order books in the offshore support sector, in turn stimulating owners to sweat existing assets harder. The focus of efficiency has turned to asset availability, rather than the promise of future cost savings offered by new technology.

“It’s fair to say that there were few analysts predicting the slide in oil prices that hit this market in the latter part of 2014,” Rofka continues. “We remain focused on anticipating real and coming situations, to provide customers with reliable technical solutions that are also flexible enough to meet changing circumstances. We are confident, for example, that Power2 anticipates a market requirement based on technological arguments that remain unchanged.”