DY Duckyang’s 10 MWh-Class Marine ESS — What the Water-Cooled Demonstration Means for System Design

Abstract

DY Duckyang has moved forward with a 10 MWh-class marine ESS business. The company has completed demonstration and certification of a 1.02 MWh-class water-cooled ESS and, building on this, is targeting supply of marine ESS at roughly 10 times that scale, at the 10 MWh class. While the battery system itself is similar between land-based and marine ESS, differing environmental constraints — installation space, vibration, and salt exposure — fundamentally diverge the cooling method and certification process design. This article organizes what completing the demonstration stage means from a system-design standpoint, and the nonlinear difficulty-escalation factors typically seen across a 10x scale-up.

1. Why marine applications require water cooling

The conclusion first: the marine installation environment (limited space, constant vibration, salt exposure) is a structural constraint that pushes the cooling method choice from air cooling toward water cooling, and this demonstration should be read as a case confirming that a sealed thermal management design functions under that constraint. Land-based ESS is often installed as containers on open sites, where air cooling alone can provide sufficient heat rejection. On ships, however, installation space is limited and the system is continuously exposed to vibration and salt, making noise management of air-cooling fans and blocking salt-intrusion paths difficult.

So why choose water cooling, which adds auxiliary systems such as piping and pumps? Because a sealed water-cooling structure can fundamentally block salt- and vibration-exposure pathways while still securing sufficient heat-rejection performance. However, the routing of cooling-water piping inside the hull and the risk of dielectric breakdown in the event of a leak remain trade-offs this structure must separately manage.

Comparison item	Air cooling	Water cooling
Heat-rejection performance	Depends on fan airflow; relatively low	Utilizes coolant heat capacity; relatively high
Salt/moisture intrusion path	Intrusion risk persists through intake vents	Can be fundamentally blocked by a sealed structure
Auxiliary system complexity	Low (fan/filter-centered)	High (pump, piping, heat exchanger, leak detection)
Periodic inspection interval (assumed, requires verification)	Filter cleaning, assumed ~3-month cycle	Piping/pump inspection, assumed ~6-month cycle
Leakage risk	Not applicable	Dielectric breakdown / fire propagation risk (requires separate management)

The inspection intervals in the table above are an assumed scenario set by reference to general marine equipment operating practice; DY Duckyang’s actual maintenance specifications are not stated in the source material and require verification.

2. From 1.02 MWh demonstration to 10 MWh commercialization

The difference between the demonstration scale (1.02 MWh) and the target scale (10 MWh) is approximately 10x. In a capacity scale-up of this kind, it is typical for thermal design, BMS communication load, and fire-propagation compartmentalization to become more difficult nonlinearly with increasing module count, rather than simply requiring more modules. The specific design changes involved in this scale-up are not confirmed in the source material and are not estimated here.

3. The weight of classification-society certification

Unlike land-based systems, marine ESS additionally requires certification from a classification society (a private inspection body that reviews and certifies a vessel’s structure and equipment). The phrase “demonstration and certification completed” means at least one formal verification stage has been passed, which is likely to serve as a reference in subsequent order-winning activity.

4. Market context

Amid tightening environmental regulations for vessels from bodies such as the International Maritime Organization (IMO), demand for electric-propulsion and hybrid vessels is increasing, and marine ESS is one of the core components of this trend. However, market-size forecasts for this specific case are not provided in the source material.

5. Items requiring verification

Item	Reason
Target delivery date and customer for the 10 MWh-class system	Not stated in source
Specific cooling system specifications (flow rate, heat-exchange method)	Not stated in source
Scope of fire-safety certification (classification-society standard name)	Not stated in source
Thermal-design and BMS communication-load changes in the scale-up	Not stated in source; not to be estimated

FAQ

Q. Is water cooling always superior to air cooling?

A. No. While water cooling offers superior cooling performance, the added auxiliary systems (piping, pumps) can reduce maintenance accessibility. The trade-off differs depending on the application (marine, high-density installation).

Q. Does land-based ESS experience transfer directly to marine applications?

A. System-level elements such as BMS and cell-management logic are shared, but vibration, salt exposure, and classification-society certification requirements must be separately verified.

Field Application Notes

Check	Method / criteria	Notes
Pre-review classification-society certification requirements	If a marine ESS project exists, request a list of relevant classification standards (KR, DNV, etc.) from the procurement team and reflect them in early design	Verification needed: the specific classification standard DY Duckyang passed is not stated in the source
Launch a cooling-method trade-off study	Rewrite the Section 1 comparison table as a template, adapted to your own installation environment (vibration, salt exposure level)	Assumed values must be replaced with your own measured data
Draft a scale-up risk checklist	Confirm that thermal design, BMS communication load, and fire-propagation compartmentalization are all included in the 1.02 MWh → 10 MWh scale-up planning document	These items become nonlinearly more difficult, so advance review is recommended
Document piping routing and dielectric-breakdown risk management	If adopting water cooling, register the cooling-water piping routing drawing within the hull and leak-detection sensor placement as a design-review agenda item	Assumed scenario (inspection interval ~6 months); requires empirical verification

Source

Newsis, “DY Duckyang Moves Forward with 10 MWh-Class Marine ESS Business,” 2026-09-16.

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