Micah Broussard sent this post, but it landed in my personal email account:
===== Message body =====
Hello all, i have been lurking for a while and following the postsbtrying to gather some information on electric drive options and this seemed like as good a place as any to jump in.
My better half and i are considering options for a full time cruising retirement on a fill displacement boat, something like a diesel duck, steel in the 50 to 60ft range.
I plan to have enough of a diesel to drive the boat and meet or needs from getting from point a to b.
What was interesting to me way how well the solar seemed to help with the zodiac so i ask would it be practical to have an electric drive as a backup drive that i could employ when our speed is not important and when the sun cooperates. I understanda i will need a propulsion bank but how much wouold that need to be if i motored electric with a large solar aray during the day then perhaps motor and recharge the back over the evening.
Money is important, don't have endless funds to buy equipment but i can justify more solar panels and batteries if they will save me from buying more diesel down the road.
So if a decent cruise speed with a diesel is 5 to 6 knots, what size motor would i need to get the boat to 2 or 3 knots on EP and what size bank and solar panel would be needed to keep it going all day?
Make sense to anyone?
--- In electricboats@yahoogroups.com, "Eric" <ewdysar@...> wrote:
>
> Hi Chris,
>
> What a great experiment! I appreciate your perseverence to take the time to cover a long distance at a slow speed. It's interesting that the 160W (4 x 40W) of solar panels would just cover the 80W motor load on average during the day.
>
> Doing a bit of the math, you used about 720Wh (80W x 9 hours), let round up to 800 for the "fast finish". You finished with about 70Wh in the battery so you used 330Wh from there. The remaining 470Wh would have come frm the panels. I've heard that a stationary panle will collect 4 to 6 times its rated capacity in Wh over the course of a day, depending on latitude and time of year. With 160W of rating, 480Wh would be a factor of three. This seems reasonable because of the moving boat and the fact that you didn't stay out for every trace of your winter daylight.
>
> And I can really appreciate your comment about 1.5kts is not exactly a speed, I can swim 3000m in an hour (1.6kts), but not for 8 hours straight.
>
> Congrats for a good day on the water.
>
> Fair winds,
> Eric
> Marina del Rey, CA
>
No comments:
Post a Comment