I should have added at a price I can afford.
Richard
------ Original message------
From: Carter Quillen twowheelinguy@yahoo...
Date: Sun, Feb 28, 2016 2:06 PM
To: electricboats@yahoogroups.com;
Subject:Re: [Electric Boats] Re: Efficiency
You've lived long enough to see it. All day electric boat travel has been around for a while now and numerous people besides me have been doing it.
Capt. Carter
On Saturday, February 27, 2016 6:10 PM, "fullkeel2000@yahoo.ca fullkeel2000@yahoo.ca [electricboats]" > wrote:
All the good ideas may have been tried but new ideas will keep coming. I am propably too old to see it but all day electric travel with our boats with Battery and solar are coming. The rate of progress is exponential.
Look what Tesla has done for cars in just a few years
------ Original message------
From: king_of_neworleans
Date: Sat, Feb 27, 2016 3:25 PM
Subject:[Electric Boats] Re: Efficiency
I'm no engineer but I agree. with commonly available motors, higher voltage and lower current, higher motor speeds and a reduction gear turning a larger prop, are going to be noticeably more efficient in spite of modest mechanical losses in the gearing. Going 24v rather than 48 does not allow use of half as big a bank. To get the same work done with half the voltage, requires twice the current and equal capacity. So comparing a 48v system with 4 12v batts in series with a 24v system with 12v batteries, they must be twice as big or be in parallel/series. Still need the same total v/ah to get the same work done, more or less. Cost of the reduction gear installation is almost trivial. You can homebrew a belt drive system with parts from McMaster Carr for probably $300. Salvaged junk, even cheaper. Small reduction gearboxes are cheap enough. Mine cost about $450 and is sealed, no maintenance and no additional parts needed and actually simplified installation because I did not have to fabricate anything for mounting a thrust bearing. That is not to say that direct drive doesnt work or doesnt have its place, becasue a motor can certainly be built that will work better in a direct drive system than what most of us are now using. I am thinking axial flow BLDC with about 4x the typical poles, large-ish diameter rotor and stator, and integral thrust bearing. Would this be significantly more efficient? Maybe, but maybe not. If there is one thing I have learned in putting my system together, it is that there is no free lunch. And all the great ideas have already been tried.
__._,_.___
Posted by: =?utf-8?B?ZnVsbGtlZWwyMDAwQHlhaG9vLmNh?= <fullkeel2000@yahoo.ca>
| Reply via web post | • | Reply to sender | • | Reply to group | • | Start a New Topic | • | Messages in this topic (15) |
.
__,_._,___
No comments:
Post a Comment