World Bunkering > News > Summer 2009 > Class looks for a sustainable future

Over the next few issues World Bunkering will be looking in some depth at the options for making more use of alternative fuels and for using existing ones more efficiently. The major class societies are well aware of the sustainability agenda and particularly the need to reduce CO2 emissions is increasingly important.

Norwegian class society Det Norske Veritas’s Per Marius Berrefjord told delegates at the recent Sustainability in Challenging Times seminar in Singapore that losing sight of sustainability issues during the recession could mean increased costs and problems in the future.

Given that social, economic and environmental imperatives are directing both governmental and corporate policies in the international sustainability agenda, Mr Berrefjord said he believed the factors contributing to the present market conditions are making long-term sustainability even more relevant.

“The world is moving towards a common agreement that doing nothing about climate change and other sustainability issues is no longer an option. This conclusion is further galvanised by the global credit crisis which has left everyone with little faith in the present financial systems,” Mr Berrefjord said.

“People and industries are changing their perceptions of what are considered acceptable practices, and they will have much higher expectations of transparency, due diligence, performance criteria and stricter regulations. Moreover, they want the authorities to lead rather than keep away.”

But against the global trend towards sustainable practices, contributions from the shipping industry have been slowed by relative indecision, lack of concerted effort and short-sightedness, he claimed.

“The shipping industry should understand that society at large is taking on major discussions as part of a mission to solve a big problem and that there is little space for special considerations in specific industries, particularly if these industries are unwilling to contribute.”

He said simple but radical changes in shipping could boost per tonne mile energy efficiency by 50% or more – an attractive prospect under any economic condition. Such changes would include enlarging the ship size; optimising sailing speed; better interactions between ports and ships; making use of technological advances in propellers, rudders and main engines; as well as improved technical management.

“The shipping industry will be expected to challenge existing conventions on the mode of cooperation between charterers, owners and other parties to act on the opportunities, especially in the current economic climate where many businesses are more concerned about short-term results,” Mr Berrefjord said.

Fuel cells will be a long-term sustainable energy solution for ships but, for immediate fuel savings, reduced environmental impact and reduced operational costs, many options are available now for incorporation in new designs, according to Lloyd’s Register.

Speaking at the SMM Istanbul, Zabi Bazari, Ship Energy Services Manager for Lloyd’s Register Marine Consultancy Services, said that energy savings as high as 40% could be achieved by incorporating new systems and approaches into the design of new ships. Looking ahead, he said that fuel cells could eventually become the main energy unit in commercial ships when low-carbon technologies and renewable sources of energy are firmly in place.

In his speech, Dr Zabi reviewed existing and potential technologies in two main categories: hull and propulsors; and engines and auxiliary machinery. To achieve a reduction in a ship’s hydrodynamic resistance, he advocated options such as optimised hull forms, the latest foul release paints, the use of air cavity or air bubble systems, the use of sails for capturing wind and solar energies. He underlined how the energy lost in propulsors can be mitigated by the use of contrarotating propellers, flow-wise integrated propeller-rudder systems and propeller boss cap fins, as well as hull mounted fins upstream of the propeller for streamlining flow at entry to propeller.

Dr Zabi identified the use of waste heat recovery systems, alternative fuels and electronic control common rail fuel injection system as the most effective and immediate means of reducing fuel consumption and emissions with existing engines. But he considered fuel cells as the most important and most likely long-term low and zero-carbon alternative. He brought the audience up to date with developments in fuel cell technologies and the likely timeline for practical shipboard application. He said that after a further three-year period of research and development, we will see a period of adoption of fuel cell technology – primarily to gradually replace auxiliary power generation engines. But full replacement of existing engines/fuels combinations by fuel cells would not be likely for 20-30 years yet, he advised. He reviewed options for rotating machinery, including high efficient electric motors and variable speed drives.

Meanwhile French-based classification society Bureau Veritas is developing comprehensive new guidelines covering the safe application of fuel cells on ships which could have important environmental and commercial advantages for shipowners and operators.

Fuel cells are electrochemical devices which convert the chemical energy of a fuel, for example hydrogen-rich gases, into Direct Current power. Until now, their application in shipping has been limited to a few pilot projects, and BV product manager Gijsbert de Jong said the main obstacle to the wider application of fuel cells in shipping is the lack of a comprehensive framework covering the technology. He explained: “By developing these new guidelines, BV is breaking the vicious circle whereby the lack of a regulatory framework limits the possibilities for building and testing the prototype applications which are essential for determining the safety and performance criteria involved.

“BV’s guidelines for the safe application of fuel cells on ships take into account all relevant existing IMO conventions and guidelines, together with a wide range of international non-marine standards. They reflect BV’s extensive in-house knowledge and expertise, and could have important commercial – as well as environmental – implications for shipowners and operators.”

There are several different types of fuel cell technology, using different types of fuel. BV said it has found that the use of hydrogen, for example, offers a number of significant advantages, not least the fact that there is an unlimited resource in atomic form and that it delivers a higher chemical energy per unit mass than does natural gas, and is non-toxic, non-polluting and non-poisonous.

BV is currently participating in the Green Tug project, an initiative led by the Offshore Ship Designers Group in the Netherlands to produce a new design for a near-zero-emission hydrogen-powered tug. As well as achieving a significant reduction in exhaust emissions, the fuel cell technology used in the new tug design also helps to increase propulsion efficiency by roughly 70% compared to a conventional diesel-direct drive installation.

Mr de Jong says: “The object of the BV guidelines is to provide criteria for the arrangement and installation of machinery for propulsion and auxiliary purposes, using fuel cell installations, which have an equivalent level of integrity in terms of safety, reliability and dependability as that which can be achieved with new and comparable conventional oil-fuelled main and auxiliary machinery. The guidelines currently have preliminary status and are subject to internal and external review. After taking into account all relevant feedback, they will be published as a Bureau Veritas Guidance Note entitled ‘Guidelines for fuel cell systems on board commercial ships’.

“The guidelines are primarily intended for application to new ships but can also be used for retrofitting fuel cell systems on existing ships, on a case-by-case basis. They are to be used in addition to all relevant SOLAS provisions. There is no limit on the type or power of the applied fuel cell system, and no limitation on the type of gas used, although the guidelines may focus on natural gas and hydrogen as fuels.

“Given the current focus on the environmental impact of shipping, the industry is looking for ways to reduce exhaust gas emissions. Also, the recent volatility in oil prices, combined with the expectation that fossil gas may become increasingly scarce, is motivating owners and operators to explore alternative means of generating onboard power. To this end, fuel cells appear to be a promising solution for clean and efficient electrical power generation at sea.”