Earlier this month, BMT announced that it will take the lead in a £1.8 million (USD 2.49 million) ‘Vessel Technology Assessment System’ (VTAS) project. The work on this project has already commissioned and funded by the Energy Technologies Institute (ETI). It will be delivered in partnership with Black & Veatch.
Sea News (SN) interviewed, John Buckingham (JB) of BMT on the issues relating to the introduction of low carbon technologies to the shipping industry.
John joined BMT in 1992 and became the Chief Mechanical Engineer in 2004. John was recently appointed as the CTO for the Vessel Technology Assessment System (VTAS) project which is being funded by the UK Energy Technologies Institute (ETI) and which is being undertaken by BMT with Black and Veatch in partnership. The following are excerpts from the interview:
SN: What is BMT’s take on Green Shipping?
JB: From the perspective of our involvement in Green Shipping, BMT has been associated with and supportive of the UK Engineering and Physical Sciences Research Council (EPSRC) funded Low Carbon Shipping project and the Shipping in Changing Climates project for the past eight years. As we are independent of manufacturing and shareholder interests, we are able to independently assess emerging energy saving technologies free of market constraints. As ship designers, our focus is to select the most appropriate technical and business solution to the challenge of making a greener ship. To this end, we have generated a stream of papers on a range of Green Shipping topics from our self-funded studies. Such papers illustrate how different energy-saving technologies can be matched to specific ships and their operating profiles to deliver lower fuel consumption and reduce greenhouse gas emissions.
SN: What are the latest avenues the company is working on to offer clean shipping technologies to the industry?
JB: As an in-house example, our study and development work on our own BMT naval ship designs shows efficiency improvements through the use of hybrid propulsion for the MARS tanker (RFA Tidespring Class) and the Royal Norwegian Navy’s ship Logistic Support Vessel (LSV) HNoMS Maud. The use of electric motors as generators at higher ship speeds and as motors at lower speeds has led to fewer and more efficiently loaded prime movers. In terms of hydrodynamic efficiency, these ships also have twin skeg-shafts, leading to a higher propeller area, improved wake flows and a better hull efficiency.
Since 2013, BMT has been working with the Energy Technologies Institute (ETI) on its Heavy Duty Vehicle (Marine) programme to improve the fuel efficiency of commercial ships. This has been approached through the assessment of multiple energy-saving technologies per ship and the identification of those technologies which offer the best prospects for making real savings in fuel consumption. As of 2018, BMT is the lead partner in the ETI Vessel Technology Assessment System (VTAS) project to develop a practical approach to predicting the benefit of a range of carbon abatement/fuel efficiency technologies on marine vessels over real-world usage cycles. Black & Veatch is a partner in this project which seeks to offer reliable technical and business reports to prospective investors.
SN: LNG and alternative energy sources are gaining momentum. What is your take on this transition?
JB: There has indeed been a gradual but steady increase in the use of LNG bunkers in the past ten years. The increased transport of LNG from key nation-suppliers to Europe and the Far East has improved availability, and the increased competition amongst suppliers has made it competitively priced too. The use of LNG bunkers to manage the challenge of ship operations in sulphur ECA and the 0.5% sulphur regulations in 2020 has made it very attractive despite the costly equipment and high integrity safety regimes required.
This steady increase in the size and number of LNG carriers together with the adoption of modern technologies to improve reliability, mitigate thermal issues with LNG storage and the matured safety regime that class societies impose, means that on-board LNG plant packages are now being designed for ease of retrofit to existing ships.
In comparison to HFO and distillate fuels, LNG as a bunker fuel burns very cleanly with little or no sulphur emissions. NOx and particulate matter emissions are generally lower than those of other fuels when burnt although this cannot be taken for granted as the combustion process can affect the exhaust composition.
Of greatest concern in the uptake of LNG as a bunker fuel is the issue of increased Green House Gas (GHG) emissions due to the vulnerability of a diesel engine to methane-slip, whereby unburnt methane slips past the piston to enter the engine casing and consequently to become ventilated into the atmosphere. As such LNG is not a solution to the GHG emissions challenge that shipping faces.
SN: To what extent is the industry ready to adapt to this crossover (towards LNG)?
JB: In general, LNG comprises 95% methane which is a GHG with a complex life cycle when emitted into the Earth’s atmosphere. The overall effect is that it has a calculated global warming potential of over 28, i.e.; by mass, its ability to act as a GHG is over 28 times worse than carbon dioxide and therefore, even small emissions are of concern. Recent measures to limit the emissions of Volatile Organic Compounds (VOC) from ships have been enacted for safety reasons, but they are also part of the need to limit CH4 emissions. Engine suppliers currently continue to address the methane-slip challenge through engine controls, exhaust catalysts and fuel blending etc. However, going forward, there is arguably a need for some form of onboard exhaust gas measurement system to identify the composition of exhaust gas, both to monitor engine health and to demonstrate compliance with current and future emissions legislation.
The interest and take-up of LNG bunkers by the shipping industry is growing both in Europe, the US and the Far East but it is starting from a very low base. With the sulphur fuel limit to be imposed in 2020 and with distillate fuel prices likely to increase, the role of low-cost LNG is likely to increase and become a useful part of the mix of marine fuels available to ship operators. The high capital cost of the cryogenic equipment together with the need to sustain high levels of equipment integrity and crew training for safety purposes will mean that LNG is not a solution for everybody, but as the necessary port infrastructure around the world continues to be introduced, it will become an attractive means of mitigating the likely higher prices of distillate fuel post-2020.
SN: How is BMT going to contribute to LNG bunkers?
JB: In alignment with our work on the modelling of energy saving devices and technologies, BMT has analysed the use of LNG as a bunker fuel in recent client-funded studies. The operations of a set of modern ships were modelled with a range of different bunker fuels. The studies addressed two and four stroke engines, both as direct drive propulsion and as gensets when part of a diesel-electric solution. The results considered the sensitivity of the engine fuel consumption data to the variability in fuel composition and the limit of methane-slip that would be a cause for concern.
Going forward, as BMT considers the feasibility and viability of various combination of carbon abatement/fuel efficiency technologies as part of the Vessel Technology Assessment System (VTAS) project, LNG bunkers will have to be considered. Although it is not a solution to the GHG emissions challenge the world faces, its increased presence as a bunker fuel means it has to be part of the assessment mix it because it is a means of mitigating future increases in distillate fuel prices and keeping below the sulphur limit.
Sea News Feature, March 2