The pods look good and appear to come with all the control gear.  

I suggest you target a 72V system.  There is some merit in having separate batteries for each side but that does not work out well with a single generator for charging.  Two separate batteries with 100Ah cells gives you 15kWh of battery, which is enough if you have a generator on board.

With the 18m proa the diesel generator is switched directly in circuit with the electric drives.  This bypasses the batteries and electronics.  This required a heavy duty changeover switch.  The benefit is another level of redundancy.

The DC generator you have nominated has standard versions of 12V and 24V.  You would need to ask if they can supply a special for 72V.  

Roof/deck space should be your limitation on the solar panels.  If you can fit 2kW of panels then do that.  There is a significant weight advantage with semi-flexible panels but they are more expensive.  The cost comes down if you buy in quantity because they are easy to transport crated in numbers.  Heavier roof panels are not packed as densely. 

Keep in mind that any weight added with the auxiliary propulsion system is going to reduce sailing performance so there is a performance penalty associated with added gear.  In this regard the semi-flexible panels make sense as they have a weight benefit over carrying extra fuel.  These panels weigh around 25kg/kW.  Depending on your cruising location you could expect 4 to 8 hours of full sunlight per day.  At the top end that means 3kg/kWh/day.  A reasonable diesel/generator will use 250g/kWh meaning the solar panels are ahead of diesel for the generator after 12 days of motor sailing.   

With respect to the panels you could expect 5 to 6kts in calm conditions with 4kW total draw from the batteries.  With 2kW of panels you could get 16kWh stored/used each day so that gives 4 hours at 5 to 6kts.  The benefit can be even more where winds a flukey using the drives to improve apparent wind to get sails working.  

Mounting the pods is not trivial.  Ideally you have a means to lift them well clear of the water.  They need good restraint when in operation and when lifted.

Rick

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