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  • Sparky42; "How much extra tons would need for these batteries to make it of any operational value, and at what cost?

    Ta Sparky....That is exactly what I was asking myself. It seems to me that if a "battery pak" is capable of powering a submarine a much smaller one could power an OPV....I simply asked about the practicality of keeping them charged by wind turbine. I have no wish to put an ESB windmill on the on the prow though the Statue of Liberty might be a runner. (Scary)

    Guess we'll just have to wait for Wartsilla to hook up a wind turbine then....."More vessels will be performing similar functions to those of today’s OPVs, which will mean more varied propulsion solutions will be required in the future. A gas engine driven full electric propulsion OPV is already in operation in Finland. This latter development followed successful market experience in the offshore segment. Clearly, the trend is towards greater versatility and Wärtsilä propulsion solutions are designed to meet these changing needs".

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    • I still think we should consider Kryptonite , and hover boards for boardings .
      Don't spit in my Bouillabaisse .

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      • Hover boards are so 2015.
        For now, everything hangs on implementation of the CoDF report.

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        • What's happening with the Type 45 should serve as a cautionary tale for all-electric propulsion systems. However much redundancy you build into such a system, they tend to suffer from cascading failures with an initial problem having a knock-on effect which leads to complete blackouts. From what I have read so far, it would appear that someone has possibly underestimated peak loads or the real output of the diesel gensets. The P60 solution, i.e. nice simple direct-drive diesels for sprint speeds and an electrical drive via gearbox PTI, is far more robust as the two propulsion systems have no interdependence. Environmental issues aside, there is no production-ready electrical system that has yet achieved the power density of the internal combustion engine which is why you don't see too many electric cars on the road. Hybrids, on the other hand, are gaining ground as a low-risk middle-of-the road solution.
          As for subs, remember they have a lower drag coefficient (when submerged) than a vessel floating on the air-water interface. Nor do they have to power through waves or wind and range on batteries is counted in hundreds (max) of miles. And that explains why air independent propulsion is such a big deal for diesel-electric subs.
          When you think that the electric motors on the Type 45 are 20MW apiece, that's a hell of alot of batteries to carry. That type of installation exists in a few places ashore (using such pleasant stuff as sodium-sulphur batteries) but we are talking industrial-size installations. On a ship you'll end up with a floating battery box with lots of hazmat, heat and flammable gases to deal with and very little, if any, space for mission systems.

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          • [QUOTE=ancientmariner;437114]
            Originally posted by Galloglass View Post

            This type of techno baiting is demeaning to the Militaryonline forum. Standard ships need their propulsion to be in a compact in hull form including all generation plant. The USS Zumwalt is described as an all Electric ship BUT all services are produced from four Gas Turbine engines and propulsion is provided by high speed electric motors.
            The Norwegians have a short route, cross estruary, car ferry running on battery powering 450kw X 2, electric motors, giving 10 knots to an 80 X 20m aluminium car and passenger transporter. Three 10 tonne batteries are involved, with one on the ship , and one on the shore either side of the route. It charges up as required either side but is not a reality for a fighting ship in a go anywhere mode.
            Air independent propulsion, or AIP, in various forms is on many modern conventional submarines manufactured by Sweden, Germany, Japan, Spain etc. The unit allows such fitted submarines to stay submerged at slow speeds for up to 21days. The French system adds a 350 tonne section to their hull and operates at 60 atmosphere pressure to discharge carbon dioxide into the sea for dispersal. Some people think this and other systems are less than 100% safe. One system was regarded as 75% safe. Despite all the technology they still need their diesels to proceed on the surface. We must remember NOTHING is free or cheap in Marine or ANY other technical systems.

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            • Originally posted by Galloglass View Post
              I simply asked about the practicality of keeping them charged by wind turbine. I have no wish to put an ESB windmill on the on the prow...

              Guess we'll just have to wait for Wartsilla to hook up a wind turbine then.....
              It's not at all practical, and if you had read or understood the figures you would realise that in order to generate the the power necessary to operate an OPV - you actually are looking at a turbine the size of "an ESB windmill" on the vessel.

              That's leaving aside the myriad of other issues raised by proposing a ship with a very large wind turbine that charges a vast battery bank, in order to turn a screw.

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              • The NS routinely operate on single engines to reduce fuel costs.

                If going down that route they would be better off with IMERC's Aeolus project

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                • Originally posted by DeV View Post
                  The NS routinely operate on single engines to reduce fuel costs.

                  If going down that route they would be better off with IMERC's Aeolus project
                  You don't propel a naval vessel with a "project".
                  For now, everything hangs on implementation of the CoDF report.

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                  • True I meant when in production

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                    • You do realise this project is at best years from production, with naval vessels being used as a testbed, and not intended as a primary powerplant?
                      For now, everything hangs on implementation of the CoDF report.

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                      • Skysails have a couple in use and more building, I'm well aware that it isn't the primary propulsion
                        Last edited by DeV; 31 January 2016, 23:59.

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                        • .
                          Pym
                          "That's leaving aside the myriad of other issues raised by proposing a ship with a very large wind turbine that charges a vast battery bank, in order to turn a screw"

                          Great Pym...
                          I'm genuinely interested in this and as I stated when first asking about "batteries" I'm not an electrical engineer. As you seem to have the figures. Could you give any idea of what size the "battery bank" would have to be to power a full electric propulsion OPV (P60 size) in other words how big is your "vast battery bank" compared to those on the new Japanese subs for example. (without AIP charging engines etc) Batteries on an OPV can be "on-charge" continuously whether by wind or LPG or a combination of both and Wind is free (2/3/4 small turbines).......Just trying to save money

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                          • I've quoted the power figures for the P60 engines, I've demonstrated the size of a wind turbine capable of equaling the output of the P60 engines. But you've ignored it.

                            I'm going to spell this out once more - the P60 utilises 2x 5440kW engines. That's 10MW.

                            A "small" wind turbine that generates 1/10 of the power of one of those engines - 500kW - has a blade 52 - 54 meters in diameter. That's 170+ feet. It's almost as long as the Peacocks.

                            EWT’s DIRECTWIND 500 kW to 1 MW turbines deliver more power and uptime with the lowest cost of energy and highest return on investment, ideal for developing new distributed generation sites or repowering existing ones.


                            As to the myriad of other issues, well, there's the drag involved, the weight, the effect on the centre of gravity, the cataclysmic effect it would have on the ships RCS and on its own ability to see. The wind will not be free when you're sailing against it. That and y'know conservation of energy, thermodynamics. Minor stuff like that.

                            But do go on - maybe tell Elon Musk about the idea, surely his cars would benefit from a small wind turbine, after all wind is free right?

                            Still though, it would make for entertaining winch training.

                            FWIW a quick and possibly dreadful calculation, since I'm no engineer either: the P60's emergency backup generator is rated at 320kW - in order to provide 320kW for one hour with Li-Ion, you would be talking about approx two tonnes of Lithium Ion batteries. (Tesla's use a 85 kWh battery weighing in at 544 kg)
                            Last edited by pym; 31 January 2016, 21:43.

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                            • Originally posted by pym View Post
                              I've quoted the power figures for the P60 engines, I've demonstrated the size of a wind turbine capable of equaling the output of the P60 engines. But you've ignored it.

                              I'm going to spell this out once more - the P60 utilises 2x 5440kW engines. That's 10MW.

                              A "small" wind turbine that generates 1/10 of the power of one of those engines - 500kW - has a blade 52 - 54 meters in diameter. That's 170+ feet. It's almost as long as the Peacocks.

                              EWT’s DIRECTWIND 500 kW to 1 MW turbines deliver more power and uptime with the lowest cost of energy and highest return on investment, ideal for developing new distributed generation sites or repowering existing ones.


                              As to the myriad of other issues, well, there's the drag involved, the weight, the effect on the centre of gravity, the cataclysmic effect it would have on the ships RCS and on its own ability to see. The wind will not be free when you're sailing against it. That and y'know conservation of energy, thermodynamics. Minor stuff like that.

                              But do go on - maybe tell Elon Musk about the idea, surely his cars would benefit from a small wind turbine, after all wind is free right?

                              Still though, it would make for entertaining winch training.

                              Don't feed the troll.
                              For now, everything hangs on implementation of the CoDF report.

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                              • So basically it would probably capsize an OPV sized vessel

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