Expedition Yacht Cú Lir

Cú Lir is the 5th Good Hope 56  Expedition Yacht to be built to plans by yacht designer Ed Joy of Camden Maine. 

Click Ed Joy's Good Hope 56. for more information on this and other designs by Ed.

Ed's design was adapted for ocean science and marine archaeology.  

KM Yacht builders in the Netherlands were chosen to build the aluminium hull for Cú Lir and Derry Connell Marine worked closely with Ed and the team in Makkum to incorproate a number of additional features into Ed's design..

The bare hull was transported to Ireland where Derry Connell Marine undertook her outfitting and also developed the design basis for the hybrid propulsion and microgrid for the boat. The microgrid was engineered and built by Baumüller and the 48V and 24V DC systems were engineered by Technical Design Solutions.

Central to the electrical system is the Danfoss liquid cooled multifunction converter with 750V DC Link. This enables the bi-directional distribution of 3 phase 400V AC, via three Victron Quattro 48/10000 units, to and from the water cooled 400V hybrid motor/generator and  the 48V DC propulsion battery bank.

                                                                            The SIngle Line Diagram 

The design was specified to have the following modes of operation and redundancy.

1.  Sailing Yacht

                 Mainsail, Staysail, Genoa or Tradewind Sail

2. Conventional Mode

                 Diesel Engine Propuslion,

3. Hybrid Propulsion PTO Mode 

                 Diesel Engine Propulsion with 22kW Electrical  Power Generation

4. Diesel Electric PTI Mode

                 Propulsion power supplied directly from a 400V Fisher Panda 25i Generator.

5. Pure Electric/Green Propulsion PTI Mode.

                Propulsion power supplied from the 48V DC Battery Bank.                      

6. Hybrid Boost PTI Mode

                Combined Diesel Engine and Hybrid Motor Propuslion

Supply to/from the 400V board to  the Victron Quattros means 3  permenant 230 V Single phase supplies and power to a seperate 24V DC battery bank which is dedicated for the supply of essential services and navigational loads.

The facility for wind, hydro or solar power at either 48V or 24V DC is also incorproated.

A seperate 230V Fisher Panda generator will keep the battery banks topped up should the renewable sources be insufficient while passage-making as a sailing yacht.

A power supply is available directly from the DC Link so that Cu Lir has the unique ability, in additon to supporting 400V 3 phase consumers, to also provide a variable supply to DC consumers at any specified voltage up to 600V.

This allows equipment such a DC powered ROVs to operate deeper in circumstances where the resistence of the tether becomes less limiting.

Eectrical cabling and installation was contracted to Green Marine Ireland using highly experienced shipyard electrcians from Gdansk Shipyards.

With less internal volume than other comparable boats employed for the same purpose the Hybrid Propulsion and Microgrid give Cu Lir the opportunity to support the deployment of a broader range of equipment.

In dpite of the inherent unsuitability of a  hull designed to sail to windward the flexibility of the boats propulsion, microgrid and energy storage systems offered the possibility to attempt dynamic positioning in "green" or "diesel electric" mode.

This has been incorporated in her design with integrated control of bow, two stern thrusters and hybrid propulsion motor.