I review the systems that go into electric propulsion for a large ship. It takes more than just batteries and a motor. Discover the other items we need. View more tips and helpful articles at www.dmsonline.us/
A slightly more subtle advantage is that when you're cruising you can turn off one more more of the generators to run the rest at their optimal efficiency. With direct diesel drive you have to design the engines for optimal efficiency in a particular sea state + load configuration. So if you're running downwind and empty you might have one out of four generators running, and that one generator is right at its peak efficiency point.
2:12 bow thruster reliability is still a major problem. The Manitowoc just hit the rail bridge in Benton Harbor Michigan last week from a bow thruster failure.
The "Georges de Joly" was a diesel-electric ship built in Germany in 1929 and immediately delivered to France as WWI war dammage. I guess diesel-electric was a known quantity early in engine boat circles because of submarines. Another detail is that we can manufacture electric motors with their peak efficiency at any point on the torque/speed curve but at higher torque their shape and the volume of "magnetic" material gets expensive (either actual magnet for BLDC, or copper used in a coil for other types), moreso than a gearbox. We see it at lower sizes, camera gimbal motors are massive torque low speed motors (for their power), the global volume of the motor being small, we can use more expensive material instead of a tiny gearbox.
Hey, I need a new refrigerator. Liebherr: I got you. I would also need a new 75t mobile crane. Liebherr: I think I have something for you as well. And I also need a complete maritime propulsion system. Liebherr: You're not gonna believe this but ... This is really interesting, not just in maritime engineering a completely integrated electric propulsion system is a bit like the holy grail. I think this would be great especially for vessels that do a lot of maneuvering, station-keeping etc. that said; the thermal efficiency of a large maritime two stroke, directly driving a fixed pitch propeller at it's optimal rpm and power setting is still hard to beat, even for land based powerplants.
You said it perfect. Yes, the large two strokes still offer better efficiency, with all the criteria you mentioned. And the large container ships and freighters still go that route. But there are thousands of ships that don't fit that mission profile. Like you said, this electric setup is ideal for maneuvering and station-keeping. This option is especially attractive to platform supply ships and offshore construction vessels. Specifically because they do a lot of station-keeping.
i don't know when Achates Power Opposed Piston Diesels will get scaled up, but something to follow there. EDIT: Rick, ( in the comments here ), mentioned that Fairbank Morse has an OP engine...and looks like the FM 38D 8-1/8 is designed for Gen-Set apps.
At 8:20 ....that cube of volume, maybe 350 cubic meters worth, does not have enough energy density by any stretch of the imagination be able to store enough electrical energy to power this vessel.
True. It's not intended to fully power the vessel. They use it for load sharing. During maneuvering, if the ship needs to suddenly increase power to the props, that energy storage / battery supplies the temporary power demand. This allows faster response time while maintaining engine efficiency. Some of those big engines can take several minutes to slowly ramp up their output. Without the battery, they would need to guzzle fuel for a fast increase in output.
Contrary to "popular belief"; electricity Is NOT a source of power. Electricity IS a form of power transmission with our most flexible end use options.
well gear boxes, and hydraulics, are Not 100% efficient either.... like Nick says, basically, the pros and cons need to be evaluated, and sometimes electrical systems come out on top, no doubt..@@rickpeters1489
Thinking of electric motors and hybrids.. A big oiltanker consumes 200 ton of fuel/day. Or +/- 110.000 $... To produce 75.000 Kw you would need 37.000 m2 of solar panels..They would probably cost +/- 5.000.000 $. Or a tankers fuel consumption in 45 days...
this will go down as the most stupid idea. They try to market this as fuel efficient. It's not. Larger diesel use 180gr/Kw. smaller engines use more than 205 gr/Kw. Every time you convert power.. you lose 4%. And if you have a LIFe battery.. you will always run a defficit due to the loading capabilities. Furthermore it is a much more expensive system
Germans usually do everything so expensive that they lose the projected gain that would be available from the application of the new principle. That aside the hybrid system has proven to be super fuel efficient in cars and this will apply here as well. Second the use of smaller engines for added together power avoids the need to create a tall engine room volume in the ship.
@@gyorgygajdos1657 no it won't. Cars have a completly different set of parameters in term of power demands. Diesel electric can have some bennefits if you compare it to a fixed rpm engine/pitch propellor. If we compare it to a vriable rpm/fied propellor system it falls really short. The problem is the electric bowthruster. For this there should be a battery, since the bowthruster is only used in short bursts. The choice for a fixed rpm/pitch proppellor was made to attach a PTO in order to provide electric power to the ship during the voyages. Is we substitute the mechanical PTO with a hydraulic one.. than the variable engine is much more fuel efficient than the diesel/electric. Since commercial ship are used to do long stints at MRC.. the bennefits from partial loads are nil...
@@rickpeters1489 You want to introduce a Hydraulic transmission between engine and propeller like diesel -hydraulic locomotives have? That solves one problem, you can decrease propeller rpm when you need to, but to increase rpm in a short burst you would still need to throttle up the engine. Thus lose fuel efficiency
