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October 2011 www.sname.org/sname/mt can be seen that these projections have already been exceeded with the current price of standard diesel oil. Additionally, the general cost of LNG will not be the cost of LNG at every U.S. location. us design- ers will have to obtain LNG costs from specic sites within the area of the proposed vessels operation. Historically, LNG costs were xed within long-term contracts, but that is no longer the case. When comparing LNG to marine diesel oil (MDO) or ULSD, it is important to note that the btu content per unit is not equivalent. While there is a btu content variance in both LNG and MDO, based upon source, as a rule of thumb, LNG has about 65% of the btu con- tent of an equivalent volume of MDO. Designing the LNG-fueled vessel LNG has been around for decades, so it is not unusual to nd LNG consultants with 40 years of experience. e LNG industry, like other industries, has many fac- ets, a number of which are not related to the marine environment. To say that one was involved with the XYZ LNG project may mean they were involved in the vaporization and distribution from shore tank systems. Someone versed in all tank containment systems may have never worked with these systems other than in a land, static environment. e designer needs to make sure that the consultant selected has experience in his or her application. LNG-fueled vessels represent an emerging technol- ogy and there currently is no regulatory review process in place in the U.S. Existing projects have been summa- rized in a Regulatory Review of Concept? report where the design had been carried to the point of identifying sizes of equipment, the preparation of piping diagram- matics, and arrangements in the areas of LNG storage and processing. To aid in review, this report should contain a matrix of the relevant rules of the regula- tory body to which it is addressed together with action items, or questions, relating to each of those rules. The only classification society that has pres- ently classed non-LNG carriers using LNG as a fuel is Det Norske Veritas (DNV). e American Bureau of Shipping (ABS) has just published their Guide for Propulsion and Auxiliary Systems for Gas Fueled Ships .FIGURE . NOX EMISSION LIMITS, MARPOL ANNEX VI 1816141210864200 250 500 750 1000 1250 1500 1750 2000 2250 2500 NOx [g/kWh] Tier I 2000 Tier II 2011 Tier III 2016 ECA limits in 2016 e use of LNG eectively eliminates the need for exhaust treatment, due to very low NO X formation in the engines as well as the absence of sulphur.