It seems that the electrical propulsion and the hybrid power plant including the battery and the inverter technology for using the battery are a common know-how, or at least considered so. Unfortunately many operators of this industry still do not know what they are doing when they try to place their solution onboard.
Shipyards naturally do not all have technical resources to define if offering is considered or not. They rely on the contractual performance criteria and – in good will and believe- trust that supplier knows what it is doing. This grey area is involving the dimensioning of the energy reserves, like the batteries, but also the battery space. You have to be Mr. Spock -level technical specialist to understand, how this “space” is defined in case of various selections made in the battery selection and dimensioning process.
THREE MISBELIEFS IN BATTERY SPACE DESIGN
When designing a battery space, which is a very relevant part of the vessel design, following misbeliefs should be avoided.
- The integrated and approved battery rack can be located almost anywhere in the ship.
This is the first misbelief. Especially with Lithium-Ion batteries, the whole ship building industry is learning while doing. Classification societies do have already rules up to date and these advises are recommended to be followed, even if the ship or boat project is not classified. The battery space design is firstly a safety measure to protect the life and health of passengers and the valuable goods, like the ship.
- Water-cooled or air-cooled batteries can be used in the same battery space design.
The battery manufacturers do provide a safety guidance, how to choose the fire protection medias and to define the conditions inside the battery space. If this guidance information is not available, please check that the supplier is suitable for ship installation.
Water-cooling and air-cooled versions of the same battery may require completely different methods of the temperature control and the fire suppression.
Battery space walling, floor and roof are usually always required A60 fire insulated.
- The battery space may be designed by the yard alone.
It is my experience to involve three parties to the battery space design (unless one of them takes more responsibilities):
- The shipyard
- The electrical system supplier
- The battery manufacturer.
Minimum requirement is that these three partners very clearly define which are under their responsibility. Responsibilities should be listed to:
- The battery space ventilation
- The cell/ module level battery protection
- The battery cooling solution
- The fire protection / The fire suppression system
- The battery pack / sub-system protection including Battery Management System (BMS)
- The battery (dis-)charge converter
- Utilization of the energy
- The energy charging system from shore / from another energy source
Of course there are good, mature players on the market and more will come. But I hope this opened eyes a little bit and made you realize that development is not as easy as ABC.
Stay safe!
Heikki
P.S. There is more support material available in our web services, like the professional marine tutorial MANAGING THE ELECTRICAL SYSTEM PROJECT IN A VESSEL.
It is supported by PDF summary notes, forming together a powerful tool to Master Class project delivery. After the tutorial you have clear picture how the project will be successfully driven and measured. Video 54 min., summary notes 20 pages.
