From: Myles Twete <matwete@comcast.net>
To: electricboats@yahoogroups.com
Sent: Fri, November 5, 2010 1:24:09 PM
Subject: RE: [Electric Boats] Re: house boat + hybrid
>We should build a spreadsheet that we can through the numbers in and get some predictive results. Or does that spreadsheet already exist?
Spreadsheets already exist for predicting boat performance based on basic factors…check our FILES section or maybe someone else can chime in with better input than I…
-MT
From: electricboats@yahoogroups.com [mailto:electricboats@yahoogroups.com] On Behalf Of Bill Spires
Sent: Thursday, November 04, 2010 9:34 PM
To: electricboats@yahoogroups.com
Subject: Re: [Electric Boats] Re: house boat + hybrid
We need that spreadsheet in the worst sort of way. Maybe a race for the fastest electric boat around a course would be good. You would not believe how fast things get fast when people race them. We could hold the first annual e boat race in Fla in the winter. Good reason to go to fla. and throw a boat in the water,, race somewhere nice and have a party when we get there and hand out some trophy's.. Have some fun, get our pictures in the paper and drink a keg with the group. Now we're e-boating. We might even learn something. Who wants to sponsor it?
Capt Bill
Reminds me of the Hobe races I used to go to. .
From: Steamboat Willie <stmbtwle@yahoo.com>
To: electricboats@yahoogroups.com
Sent: Thu, November 4, 2010 10:55:34 PM
Subject: Re: [Electric Boats] Re: house boat + hybrid
| That might work for a while but houseboats tend to gain weight, even if you build 'em light in the first place. And the finer the hulls are, the less weight they'll carry. "catamaran" style houseboats still have pretty blunt hulls and aren't known for their lines OR their weight capacity. My guess by the time you add a half ton of batteries and a genset you'll be good to get 5 kts with 20 hp...
we are talking displacement speeds here so the weight will have more effect on acceleration than speed and he will need 40' of water line length to hit 8.47 knots so he will have lots of load capacity. I'm thinking 43' or so to keep him below hull speed and 2 - 10 hp motors that would run at 60% power most of the time and only put out max power for short burst to maneuver or accelerate. A light weight structure built out of aluminum and maybe a trampoline area like a big catamaran. Another advantage of slowing down the speed is that the genset will supply more of the power for movement. Some of the 40-50' house boats here on the lake idle at say 5-10 hp at 4-5 knots and at full throttle (140 hp) get all the way up to 7-8 knots. These are barge type hulls and develop resistance and skin drag really fast. Catamarans and Proas can beat the hull speed formula. If this boat is only going on the river and waves are less of an issue and it can be built to flex you could keep the weight down. I am thinking a proa might be a really fast electric boat design. If you took and old rowing shell and put an outrigger on it I think it might go pretty well on electric power. Anybody have an old shell they want to donate to try it out?
We should build a spreadsheet that we can through the numbers in and get some predictive results. Or does that spreadsheet already exist?
Capt. Bill
From: Steamboat Willie <stmbtwle@yahoo.com>
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