Soryu and New Japanese Submarine Class Table

Anonymous kindly provided many details on September 23 to 30, 2020, regarding diesel generators (diesels) and Lithium-ion Batteries (LIBs) for Japan's newest submarines. I have noted these changes in the revised  SORYU TABLE below the details.

Anonymous's September 23 to 29, 2020 comments are:

"Japan’s Ministry of Defense (MoD) is building 3,000 ton submarines as successors to the Soryus, and the fourth ship (02SS) [1] will be equipped with new diesels [2].

[1] "SS" numbers and Financial Year names for Japanese submarines are based on the era of reigning Japanese Emperors. So that is the eras of former Emperor "Heisei" and present Emperor "Reiwa". Hence the names of the newest (post Soryu) Japanese submarines are 29SS, 30SS, 01SS and 02SS for Financial Years 2017 (Heisei 29), 2018 (Heisei 30), 2019 (Reiwa 01) and 2020 (Reiwa 02), respectively.

[2] The final two Soryus, which use LIBs, are 27SS and 28SS. LIBs makes them "Soryu Mk IIs". The early New Class 3,000 ton (surfaced) submarines (29SS, 30SS, 01SS) will be equipped with 12V25/31S diesels which are longer stroke versions of the 12V25/25SB used for all Soryus. Performance of new diesel generators for 02SS seems to be improved significantly.

[Pete Comment: the New Class will likely be assigned a name of a Japanese mythological creature (eg. a mermaid or a different dragon than "Soryu", etc)] 

02SS will also equip with improved LIBs. The electrical system for LIB-submarines is summarized as follows:

-  Soryu Mk IIs (27SS, 28SS): LIBs type SLH (see SLH explationation below); with also have  
   12V25/25SB diesels

-  first 3 subs of the New 3,000 ton Class (29SS, 30SS, 01SS): LIBs type SLH and
   2 x 12V25/31S diesels

-  4th sub of 3,000 ton class (02SS): LIBs type improved SLH [1], new diesel [2]

[1]  According to the ex-Minister of Defense, improved SLH LIBs with better performance had been
       developed but was not immediately adopted due to defense budget shortfalls.

[2]  As an item for a new diesel was not found in R&D planning for submarine, a new diesel might be
       a 12V25/31S based on an existing diesel (e.g. the 12V25/25SB).

Noise testing by KHI, for new or modified diesels took place in a simulated pressure hull, which was constructed by KHI in 2019. This strongly suggests that the new diesel 02SS is made by KHI ie. Kawasaki.

Judging from specifications of the NDS (National Defense Standard), output of 12V25/25S is 2,000kW  and it may be an evolution from the diesel for 29SS (12V25/31S). Output of a new diesel for 02SS is expected to be more than that of 12V25/31S (2,500-2,800kW) and to be 3,000kW or more.

In this case of a 3,000kW-output, the indiscretion ratio (IR) of 02SS might be 4%-5%. As ex-Vice Admiral Masao Kobayashi [see his photo and biodata here] suggested charging of LIBs would be conducted outside the operational sea area. Then the real IR of 02SS may be considerably lower (less than 1%?). [Pete Note: "A submarine’s indiscretion rate [or ratio] is defined as the percentage of time a submarine spends snorting. This indiscretion rate depends strongly on the energy discharged from the batteries and the diesel generators’ capacity to recharge the batteries. Typical snorting indiscretion rates [of LAB submarines] are between five and twenty per cent"]

[1] NDS F80182D [General Rules of Rotating Electric Machine for Ship] 4.1 a) and 4.1 g) specify rated output of AC generator and rated speed AC generator driven diesel, respectively, as follows:

4.1 a) 80, 100, 160, 200, 300,400, 500, 600, 800, 1000, 1200, 1500, 1800, 2000, 2500, 2800, 3000 [kW]

and

4.1 g) 900, 1200 or 1800 [rpm]

[2] SHIPS OF THE WORLD 2020, No930, Page109

“Output of KAWASAKI 12V25/25S for Oyashio is 3400PS (=2040kW)”

Latest information on battery arrangement for Oryu (27SS), a Soryu Mk II, was reported at [1] below. There, additional LIBs are loaded in a double deck arrangement in place of LOx for AIP tanks [as there is no AIP on Mk IIs] see [2] below. 

Then, amount of batteries in Oryu (27SS) and Toryu (28SS) seem to be twice as much as those in Soryu Mk Is [which have LABs and much space taken up by AIP chemicals and Stirling engines], suggesting loading of 960 LIB-arrays (total energy, 70MWh?). 27SS and 28SS might show better performance previously reported here, in Submarine Matters.

[1] SHIPS OF THE WORLD 2020, No935

[2] at http://gentleseas.blogspot.com/2016/09/pressure-hull-alloys-debate-titanium.html see the “Cutaway diagram of a Soryu submarine”

In the Oryu (27SS), LOx tanks in section 10 are removed, doubled decker structure is adopted for section 10 and filled with additional LIBs (240 LIB-arrays x 2).

SLH

Japan’s Ministry of Defense (MoD) discloses purchasing information in detail but not perfectly. SLH is a model name of a LIB for submarine. SLH is made by GS YUASA. Specifications of equipment are classified as “old”, “revised” and “new” for existing, revised and new models, respectively.

Specification class of SLH for 02SS in FY2020 is “revised”, suggesting that LIB for 02SS is an  improved version of LIBs (“old” SLH) for 01SS. If LIB is fully model changed, new model name is selected and specification is “new”.

Specification of the 2 diesels for 02SS in FY2020 are classified as “new”, suggesting that they are a new model.

 In 27SS, improvements other than LIBs are achieved, and 28SS Toryu improves 27SS somewhat.

By the way, an ex-Vice Admiral (not Kobayashi) of JMSDF said nuclear submarine is needed in future, because even LIB-submarine is still powerless (10% energy of nuclear submarine). RAN might have the same idea for Australia."

Anonymous correction comment of September 30, 2020 is:

12V32/25, 12V32/25S, 12V25/31 are wrong descriptions. Correct description is 12V25/31S [for 29SS, 30SS, 01SS and perhaps 02SS?]. 

12V25/25S for Oyashio and 12V25/25SB for Soryus [ie. 16SS to 28SS] are correct description. 

Meaning of 12V25/25SB means a V12 engine, 25cm in bore, 25cm in stroke, second version (B). In 12V25/25S, A for first version is omitted. 

(Life cycle cost of 29SS [New 3,000 ton Class] series) 

According to formal report by MoD, when 12 x 29SS are operated for 24 years, life cycle cost from design to disposal is 1.6 trillion yen (21 B AUS) except improvement of equipment:
-  37.4 B yen for R&D stage,
-  890 B yen for production stage,
-  671.6 B yen for operation/maintenance stage,
-  0 B yen for disposal stage,
Total = 1.6 trillion yen [1].

[1] In case of 30 years-operation [as in Australia] and one replacement of sonar system (2B yen per a submarine), life cycle cost for 12 submarines may: be 1.7 trillion yen (22.4 Billion AU$)."
[Pete Comment: This indicates if Australia has chosen a Japanese design Attack class submarine Australia is likely to have saved a vast amount of money.]

[See most of the diesel and battery details incorporated in the revised SORYU TABLE below.]

SORYU TABLE. as at October 1, 2020. 

SS No. Diesel Type Motor	Build No Name	Pennant No.	MoF approved amount ¥ Billions FY	LABs, LIBs, AIP	Laid Down	Laun -ched	Commi ssioned	Built By
5SS Oyashio 2 Toshiba motors	8105 Oyashio currents	SS-590/ TS3608	¥52.2B FY1993 2 x 12V25/25S  diesels for all Oyashio class (each diesel 2,000kW)	LABs only	Jan 1994	Oct 1996	Mar 1998	KHI
6SS-15SS Oyashios  10 subs 2 Toshiba motors SMC-7?	8106 -8115 various	SS-591-600	¥52.2B per sub FY1994-FY2003	LABs only	15SS Feb 2004	15SS Nov 2006	15SS Mar 2008	MHI & KHI
16SS Soryu/ Dragon class  Mk I	8116 Sōryū dragons	SS-501	¥60B FY2004 all Mk.1 LAB+AIP Soryus have 2 x Kawasaki  12V25/25SB  diesels may total (6,000kW sidebar) see and + 4 AIP SMC-8 motor	LABs + AIP	Mar 2005	Dec 2007	Mar 2009	MHI
17SS	8117 Unryū	SS-502	¥58.7B FY2005	LABs + AIP	Mar 2006	Oct 2008	Mar 2010	KHI
18SS	8118 Hakuryū	SS-503	¥56.2 FY2006	LABs + AIP	Feb 2007	Oct 2009	Mar 2011	MHI
19SS	8119 Kenryū	SS-504	¥53B FY2007	LABs + AIP	Mar 2008	Nov 2010	Mar 2012	KHI
20SS	8120 Zuiryū	SS-505	¥51B FY2008	LABs + AIP	Mar 2009	Oct 2011	Mar 2013	MHI
21SS LIBs Concept Research Project			No 21SS built. It was an 8 year research project on LIBs. 1st LIBs sub launched was 27SS in 2018.
22SS	8121 Kokuryū	SS-506	¥52.8B FY2010	LABs + AIP	Jan 2011	Oct 2013	Mar 2015	KHI
23SS	8122 Jinryu	SS-507	¥54.6B FY2011	LABs + AIP	Feb 2012	Oct 2014	7 Mar 2016	MHI
24SS	8123 Sekiryū	SS-508	¥54.7B FY2012	LABs + AIP	15 Mar 2013	2 Nov 2015	13 Mar 2017	KHI
25SS	8124 Seiryū	SS-509	¥53.1B FY2013	LABs + AIP	22 Oct 2013	12 Oct   2016	12 Mar 2018	MHI
26SS	8125 Shoryū	SS-510	¥51.7B FY2014 last SMC-8 motor	LABs + AIP	2014	6 Nov 2017	18 Mar 2019	KHI
27SS a Soryu "Mk II" as it has LIBs. 1st Soryu Mk II	8126 Oryū 11th Soryu	SS-511	¥64.4B FY2015  with 2 12V25/25SB diesels (totaling 4,200kW)  SMC-8B motor Soryu Mk IIs may have twice as many batteries as Mk Is, ie 960 LIB-arrays in Mk IIs, other improvements	LIBs only (SLH type)	Nov 2015	4 Oct 2018	5 Mar 2020	MHI
28SS Soryu Mk II, 12th & final Soryu	8127 Toryu	SS-512	¥63.6B FY2016 still 12V25/25SB.  "2,900t" surfaced	SLH LIBs	Jan 2017	6 Nov  2019	Mar 2021?	KHI
29SS First  Taigei Class ("Great Whale) 3,000 ton	8128 Taigei		¥76B FY2017 (Heisei 29) Higher ¥76B budget may be due to being first of new Taigei class with  new 12V25/31S  diesels (each 2,500-2,800kW?)	SLH LIBs maybe 960	2017?	14 Oct 2020	Mar 2022	MHI
30SS  New Class named after mythological creature		SS-513	¥71.5B FY2018  (Heisei 30) 12V25/31S diesels	SLH LIBs	2018?	2020?	2022?	MHI?
01SS  New Class	8029?	SS-514	¥B? FY2019 (Reiwa 01) 12V25/31S  diesels	SLH LIBs maybe 960+	2019?	2021?	2023?	KHI?
02SS  New Class	8030?	SS-515	¥B? FY2020 (Reiwa 02) Improved SLH LIBS 2 x Diesels uprated 12V25/31S or newer  (each likely 3,000+kW?)	Impro ved SLH LIBs	2020?	2022?	2024?	MHI?
03SS	8031?	SS-516	¥B? FY2021	LIBs	2021?	2023?	2025?	KHI?
04SS	8032?	SS-517	¥B? FY2022	LIBs	2022?	2024?	2026?	MHI?
05SS	8033?	SS-518	¥B? FY2023	LIBs	2023?	2025?	2027?	KHI?
06SS	8034?	SS-519	¥B? FY2024	LIBs	2024?	2026?	2028?	MHI?
07SS	8035?	SS-520	¥B? FY2025	LIBs	2025?	2027?	2029?	KHI?
08SS	8036?	SS-521	¥B? FY2026	LIBs	2026?	2028?	2030?	MHI?

Key to Table: Table information exclusively provided to Submarine Matters. LABs = lead-acid batteries, AIP = air independent propulsion, LIBs = Lithium-ion Batteries. 
¥***B = Billion Yen. MHI = Mitsubishi Heavy Industries, KHI = Kawasaki Shipbuilding Corporation of Kawasaki Heavy Industries. 

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Anonymous and Pete