Solar Catamaran Completes Third PNW Season.

Discussion in 'Electric Propulsion' started by pacific green, Aug 23, 2018.

  1. pacific green
    Joined: Oct 2017
    Posts: 10
    Likes: 1, Points: 3
    Location: earth

    pacific green Junior Member

    The 1964 Bill O'Brien Bobcat Catamaran 25.5 LWL 14.5 Beam and 6000 lb displacement completed her third season plying the waters of the Pacific North West. The vessel again this year was nothing short of amazing to live on and experience.

    People are constantly amazed by the Canadian registered "Black Hole Sun" MMSI# 316031036. From her fully redundant 36 volt GPS spot lock system to her 48 volt 400 amp hour Winston 20 Kwh main propulsion battery or her 2160 watts of solar power the question always asked is "Is it powered by solar?"

    The vessel has basically an unlimited range for a minimal fuel requirement. We have documented footage of how amazing electric really is on the water in excess of 500 videos now. With a battery only range of 75 km or more on a full charge we can make some incredible legs all in silence and in the 4 to 5 knot range.

    This year we added another Honda 2000 into the configuration. This helped us with dual redundancy on the generators as well we produced 10 more amps from the chargers. The generators could then be both ran in eco mode for six hours putting back 240 amp hours back into the bank plus whatever the sun gave us that day from the solar.

    Compared to last year the second Honda 2000 was a blessing. Figure a four hour run time driving 2 chargers for 30 amps only returning 120 amp hours back to the battery. The acquisition of the second Honda gave us some freedom for some really impressive 6 knot sustained sprints and the ability to get from A to B faster.

    The next season will incorporate two more 48v battery chargers if suitable additions can be sourced. I have almost given up finding two more identical chargers to the ones I have now Lestronic 17910 models. Those are amazing chargers.

    I tried for two chargers this year but struck out on each purchase only having to return at my expense. Since I have an Eagle Perfomance Pro 36 volt charger driving the 36 volt Xi5 105 lbs thrust 60" Saltwater Bow Mount GPS and the 36v 72 amp hour Calb battery bank, I may very well opt to simply bite the bullet and order a couple of 48v Eagle Performance Pro chargers.

    In the end though it brings me back to square one with amps in... Factor now if you will max 30 amps from each generator times two for a four hour run time. 240 amps returned for four hours of wot Honda plus the 80 amps returned during the same time from the sun and I have produced 320 amp hours. The bank is now practically full if not at capacity.

    This year when we had the sun we could charge for 50 amps. We were really appreciative of that when we had the sun. One day we pulled over 7 Kwh or 151 amp hours from the panels. In all honesty I will order the chargers simply for extra redundancy. Hard to beat eco mode sound levels or the option for a fast charge - whether it gets used or not will have to be seen. Certainly enjoyed the dual eco mode action this year. Being able to charge at 75 amps would be priceless at times.

    Solar Catamaran
    Dejay likes this.
  2. Dejay
    Joined: Mar 2018
    Posts: 721
    Likes: 138, Points: 43
    Location: Europe

    Dejay Senior Newbie

    Thanks so much for sharing all your info, it's awesome to hear this is actually workable! There is very little info about how solar powered boats actually perform in real life.

    Could you share more data points on actual power consumption in watts at a certain speed? I'd be interested to see how energy efficiency per km changes with speed.

    Do you have video or pictures how the actual boat looks like with the solar panels? I couldn't find any.

    So 75km (40.5 Nm) trip per battery charge with a 20kWh pack, that would mean 0.267 kWh per kilometer or 0.493 kWh per nautical mile. That looks very efficient! The Nissan leaf needs 0.16kWh per kilometer. A car goes faster of course, but you can't live in it.

    The bobcat seems to be a very lightweight boat in displacement / LWL. I've only found the Skoota 28 and Jazz 30 that are lighter per length or "roof space for solar power".

    The batteries you use weigh about 215kg? (EDIT 20kWh 16 x 400 Ah Winston at ~10.5kg/kWh)
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