KAPOWAI

Kapowai is Above the Waterline's showboat.   She is all-electric with huge batteries and an electric engine.   Being the showboat for an electronics installation company, she is loaded with the best Raymarine equipment.  

Kapowai has a  new Propulsion Marine 5 KW electric drive. 

Kapowai has 10 big batteries,  6 8D batteries, 4 shown here underneath the aft berth where the fuel tank, 2 next to the electric engine, and 4 4D batteries underneath the starboard settee.   On an electric boat it is better to think of battery capacity in terms of kilowatt hours, rather than amp hours.    Kilowatt hours are easy to compute, being amp hours multiplied by voltage.   Consider voltage to be 12.5 volts per battery, because that is the average state of charge.

6 - 8D batteries x 12.5 volts per battery x 245 amp hours =  18.228 KWH

plus 4 -4D batteries x 12.5 volts x200 amp hours = 9.920 KWH

for a total of 28,148 KWH     

Although you can use all of the 28 kilowatt hours, if you use over half you will shorten the batteries life.    Therefore we consider the battery bank to have 14 KWH of useable energy.   Its nice to know that you have a 14 KWH reserve should you ever need it.

Notice how the batteries are strapped down.   PVC pipe is glassed over attaching it to the hull.   The straps pass around the PVC pipe (where there is no fiberglass).  2 lb. two part foam is placed around the batteries to pack them into place.   These batteries do not move and are thus a part of the boat.   There central location low down on the boat actually help the sailing characteristics of the boat.    Catalina 30's are light for their size, so the extra weight helps.

At 2 Kilowatts she makes 3.5 knots and running for 6 hours, Kapowai has a useable range of 21 nautical miles.   She happily cruises the near side of the channel islands, the farside is more on the adventurous side of things!

Kapowai has a 24 volt DC system which powers the electric engine, the Raymarine E120 and DSM 300 sounder module.   The 24 volt battery is center tapped to provide 12 volts for everything else.   A Vanner 24 volt equalizer transfers power between the two batteries to keep them balanced.     The panel shown below switches 12 and 24 volts DC on the left, and 110 volts on the right.   The switches in the middle are for turning on the wind generator.    The second switch allows the wind generator to be hooked up to either 12 or 24 volts.

Kapowai has one of the most sophisticated marine navigation systems money can buy.  Her E 120 chartplotter has radar, digital sounder, automated identification system, satellite weather, and 3D cartography with satellite photo overlays.

What you want to see :)    CPA   .398 nm

And what you don't want to see :(   CPA 352 ft )

The Advanced Elements inflateable kayak is our shore vehicle.    The Kayak costs $600 and the paddle costs $400.   The carbon fiber paddle is very light and ergondynamically designed which makes a big difference to how long you can paddle comfortably.

Can't beat the view at the end of the day!