Whenever I review a #Yacht I always look at the crusing speed and the range which usually is expressed at a Lower speed. This is what guided me to do this post: Efficiency, Speed and Emissions. As you know consumption are directly correlated with #CO2. The more you consume the more CO2 you emit in the atmosphere. So if you sail burning 200 lt/hrs you are producing about 3 times the amount of CO2. This means that for each litre of fuel you save you are saving a lot of CO2. So if an owner reduces the speed of his yacht he will save an enormous amount of CO2. Usually a full displacement yacht is designed in terms of power selection in order to reach the maximum theoretical speed of the hull. For example a 45 mt yacht has a maximum theoretical speed of about 15.5 kn. A 45 mt superyacht requires at 10.5 kn half of the power needed to reach 15.5 kn. Usually superyacht of this size tend to cruise at 10.5 in order to optimize not only the consumption but also the comfort of it’s guests. Engine manufacturer (such as MAN Energy Solutions , Caterpillar Marine , Yanmar , FPT Industrial , Rolls-Royce ) optimize engines in order to be at the maximum #efficiency point in the design cruising speed of the yacht. So an engine designed to produce 1000 kw will be slightly more efficient in terms of specific consumption (gr x kwh) at 800 kw then the same It goes without saying that if you look at this in the consumption per nautical mile scheme there is an enourmous amount of saving. Often is given little attention to the importance of keeping hull and propellers clear from #fouling. This can save an enormous ammount of CO2 in fact a dirty hull will dramatically influence vessel consumption and there fore performance. Selecting the proper anti fouling (such as the one produced by Chugoku Marine Paints, Ltd , Seajet Yacht Paint ) according to the use of the yacht and moreover ensuring that the hull remains always clear from antifouling is of paramount importance. Many think that it’s important to houl out of the water the yacht every year but in reality moving the yacht regulary (avoiding to stay unused for several months in hot water) and inspecting the hull on regular interval will sort out a lot of the problem if the right anti fouling has been applied in the right way. To reinforce what I’m writing take into consideration that certian commercial vessel get out of the water only once every 5 years. Obviusely new yachts with the arrival of hybrid propulsions and batteries allow some time to reach even more efficiency compared to traditional yachts. I will soon write another article piece about hotelerie consumption.
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