AK,
I think that you're right on track. One advantage of the Honda generator is that it's not part of the boat. If you have other charging sources available, then leave the Honda ashore. However, if you've got it along, and your onboard charger is the right voltage (not a given in Europe), then you'll have an indefinite amount of low speed range. Just a few things to keep in mind about the practical output of a small generator. First, a Honda 2000 has a continuous rating of only 1600 watts. Then there are some losses inherent in the charger itself. And finally, charging voltages are higher than the nominal voltage of the drive system and batteries, i.e. 48V charging is close to 54V so a given wattage yields fewer amps. Keeping all of that in mind, a properly sized, modern PFC (power factor corrected) charger should be able to deliver a continuous 25A to a 48V system from a Honda 2000. That should drive most conversion discussed here at 4kts or more, your boat should be light so you might see somewhat higher speeds under "honda power".
You can also see that PV solar panels have limited value for direct propulsion until the array gets pretty big. Think about how big and heavy a 1200W array would be. That is going to translate to about 1.5hp or less at the motor. The Honda can provide the same power in a much smaller, portable package. I'm not saying that solar panels are not useful, they are great for charging your batteries over longer periods, but direct solar drive has a number of logistical problems to solve (size, weight, cost, available sunlight, etc.).
And another great part aboput the Honda is that you can delay the investment in a portable generator until your boat is fully operational and you have determined your needs in the way that you actually use the boat.
Fair winds,
Eric
Marina del Rey, CA
--- In electricboats@yahoogroups.com, "ams_ak@..." <ams_ak@...> wrote:
>
> Thanks for the input all.
>
> -Eric
> The 10 kWh / Gallon measure is interesting, and another way of showing that the 80*100Ah setup would not be a bad idea. Storage would then be 25.6 kWh, usable roughly 20 kWh. Bit more of a buffer and performance is increased in spite of the weight gain, due to better overload power (or so it is said).
> Still a 40 kW motor is going to eat any battery pack tout suite at WOT.
>
> Which ties into the usage / generator replies.
> I've considered generators from the get-go, and a wide variety at that. I own a little Solar Panel resale and installation business, so you can understand I lean slightly more toward the so called renewable generators. All in all, there are just so many ways of getting juice into your pack, and that is one of the cool features of a battery driven vehicle.
> For my conversion, or at least for now, I feel I can leave all the generating outside of the boat. I have enough power for day trips city side. When i go nature / lakeside I have the advantage of knowing people all along the way, so a limp in to port is always real close. Seaside however, that might be the day I want the Honda.. or a friend with a bigger boat!
> The city of Amsterdam is also helping out by installing a few new charging stations every month, with free juice (until 03-2012).
>
> All this talk of draining the batteries is distracting. There are A LOT of parts which can fail before I get that far :)
>
> AK
>
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