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I would like to know the reasons wh
- Thread starter jfreddy
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MikeHalloran
Mechanical
My marine experience is limited to large yachts.
They tend to have fancy 'fuel polishing' systems to remove the usual dirt and water before it reaches the engines, so as to avoid an engine stopping at sea. I guess that is fuel management.
When they buy fuel, they often sign an affidavit that the fuel will be used offshore, so they can legally buy untaxed/dyed fuel. That minimizes fuel cost, if not consumption.
I'd imagine that a power generation facility, since it doesn't move often, would also be entitled to buy untaxed/dyed fuel, and it would be in their interest to also remove water and dirt before attempting to inject the fuel into a Diesel or a burner.
So, one way I can see for a yacht to control its fuel consumption where a powerplant cannot is by controlling demand, which in the marine industry is sometimes called 'slow steaming'. E.g., a power producer cannot directly control the demand on itself except by shutting off customers, or persuading them to buy power at off-peak hours.
Whereas, if a yacht owner is not expected at a particular port for a week, and the boat can get there in two days, said owner might ask the captain to proceed at a more leisurely pace and arrive in four or five days.
Did that answer any part of your question?
Mike Halloran
Pembroke Pines, FL, USA
They tend to have fancy 'fuel polishing' systems to remove the usual dirt and water before it reaches the engines, so as to avoid an engine stopping at sea. I guess that is fuel management.
When they buy fuel, they often sign an affidavit that the fuel will be used offshore, so they can legally buy untaxed/dyed fuel. That minimizes fuel cost, if not consumption.
I'd imagine that a power generation facility, since it doesn't move often, would also be entitled to buy untaxed/dyed fuel, and it would be in their interest to also remove water and dirt before attempting to inject the fuel into a Diesel or a burner.
So, one way I can see for a yacht to control its fuel consumption where a powerplant cannot is by controlling demand, which in the marine industry is sometimes called 'slow steaming'. E.g., a power producer cannot directly control the demand on itself except by shutting off customers, or persuading them to buy power at off-peak hours.
Whereas, if a yacht owner is not expected at a particular port for a week, and the boat can get there in two days, said owner might ask the captain to proceed at a more leisurely pace and arrive in four or five days.
Did that answer any part of your question?
Mike Halloran
Pembroke Pines, FL, USA
- Thread starter
- #3
in the marine industry various types of fuel are used in terms of viscosity and sulfur content. some coastal areas do require marine ships to comply with local emission regulations, especially the North Sea and the Baltic region and the North American east- and west coast. that means that in certain areas "dirty" fuel is no longer allowed - the emissions are limited to such that would be generated when using 0.1 percent sulfur fuel. that means you either will need to have on board various fuels or have to install a "scrubber" - a device that takes out a large part of the sulfur emissions. in US coastal waters also the amount of NOx emissions is limited.
quite a few large ships nowadays use a "blending on board system" - they can both blend various fuels and also blend the engine cylinder oil for the slow two stroke engines in accordance with both sulfur content of the fuel and engine load.
apart from that they sometimes do "slow steaming" which also calls for both a change of Total Base Number of the cylinder oil and the feed rate of the oil to the cylinders.
that together can make up a quite complicated situation, but the economics are such that it is worth the effort.
in power generating plants where basically the same type of engine may be used usually emission regulations call for a particular ("clean") fuel type, so there no longer is much choice. they also do not experience the variety in load, so that a standard type of cylinder oil may be used continuously.
quite a few large ships nowadays use a "blending on board system" - they can both blend various fuels and also blend the engine cylinder oil for the slow two stroke engines in accordance with both sulfur content of the fuel and engine load.
apart from that they sometimes do "slow steaming" which also calls for both a change of Total Base Number of the cylinder oil and the feed rate of the oil to the cylinders.
that together can make up a quite complicated situation, but the economics are such that it is worth the effort.
in power generating plants where basically the same type of engine may be used usually emission regulations call for a particular ("clean") fuel type, so there no longer is much choice. they also do not experience the variety in load, so that a standard type of cylinder oil may be used continuously.
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