Thursday, December 25, 2014

RE: [Electric Boats] running the motor on genset

 

Steve,

What size diesel engine(or engines)   your two 12hp electric motors replace?
you say that you do hull speed with your genset but what about in rough weather?

Martin

To: electricboats@yahoogroups.com
From: electricboats@yahoogroups.com
Date: Tue, 16 Dec 2014 07:08:55 -0500
Subject: RE: [Electric Boats] running the motor on genset

 

Martin,

I have a 41 foot Cat with the Solomons Tech system, Twin ST74 motors putting out 12HP(24HP) on each side. I also have a 16 KW Genset that meets the needs to get to hull speed, around 8 knots. With a variable speed  output on the genset I charge the batteries then any excess power is sent to the motors. Now here's the kicker. I run at 144V DC which means I only need around 80A to run at hull speed so the 16KW genset meets the needs of the motors. By setting the genset output to anywhere from 144V to 164V DC I can safely charge the batteries then run the motors with the genset since the amperage is reduced to the batteries. I can run all day on genset only if I had to.

So to answer your question yes you can but Genset size would depend on your voltage output (amps) of the genset and the motor requirements.  This sounds like you're looking at a mono boat in the 40 ft range?

 

Steve in Solomons MD

Lagoon 410 S2E

 

 
 
did someone run his motor only on generator power without any batteries? was this discussed before? would it need a too big generator ? I was thinking of a 15 hp motor driven by a 25kw generator? 
any opinions?
 
Thanks, Martin





__._,_.___
Posted by: mountain man <mdemers2005@hotmail.com>
Reply via web post • Reply to sender • Reply to group • Start a New Topic • Messages in this topic (7)

.

__,_._,___
Posted by at No comments:

Re: [Electric Boats] FW: New Member from Iceland

 

I am analytical and look at numbers.
As such, the project is expensive but doable.

25 kWhr usable load needs a minimum 30 kWhr battery (similar size as a tesla), and with some margin 40 kWhr.
At 500 $ / kWhr, ==> 20.000$.
At, say, 100 Wh/kg, => 400 kg battery mass.

Thus, its technically feasible, since the motors will be small and light.
The extra battery mass is likely still doable.

I would suggest planning around 100.000$ for systems cost.
Note requirement for proper schematics, survey, a licensed marine engineers write-off on safety etc. as its a commercial vessel.
Perhaps double insulated cables.

In a fjord (Norway) the engineers costs and licensing will be reasonable.

All prices are in line for any other custom commercial, insured, build, in my opinion and in my experience.
Any custom build will have the same safety and licensing costs, anyway.

The last thing you look at, or should think about, is motors, controllers etc.
The first thing you look at is systems cost, legal, engineering practicalities, and any suitable "white-box" technology will slot right in.

All good engineering solutions are pretty much comparable, and any one will work.
The legal aspects are about 2/3 the total cost and work, and should be the overriding focus, in the initial business plan.

In the us, or here in spain, the legal aspects might easily cost more than the 100k budget I mentioned.
In scandinavia, not necessarily.

I can advise further, if there is interest.

On 24/12/2014 20:57, 'Myles Twete' matwete@comcast.net [electricboats] wrote:
 

Any feedback for this gentleman?

 

From: electricboats-owner@yahoogroups.com [mailto:electricboats-owner@yahoogroups.com] On Behalf Of Stefán Brandur Jónsson stefan@martolvan.is [electricboats]
Sent: Tuesday, December 23, 2014 9:11 AM
To: electricboats Moderator
Subject: Re: FILE - Welcome

 

Hi All 

 

I'm Stefan from Iceland, I'm an electronics field engineer by profession and bit of an boat and energy efficiency enthusiast.

My latest project is an feasibility / business plan for an catamaran tourist boat for using in my fjord that is for the most part very shallow, I think that an electric Jet drive would be the best fit where I need to overcome currents up to 8 knots in graceful manner. are there any ones that have some good advice on motor, battery and controller choices. My goal is to go electric only on approx hour trip on approx 25 KW load (max power 2 x 28 KW).

Look forward to comments.

,_._,___

--   -hanermo (cnc designs)

__._,_.___
Posted by: Hannu Venermo <gcode.fi@gmail.com>
Reply via web post • Reply to sender • Reply to group • Start a New Topic • Messages in this topic (2)

.

__,_._,___
Posted by at No comments:

Wednesday, December 24, 2014

Re: [Electric Boats] Multiple charging sources charging 48v bank?

 

They make AC and DC micro inverters,  the DC ones are sometimes call optimizers.  Their advantage is they you can have panels installed any place you like one panel being shaded or at another angle would not block current from other unshaded panels. The down side is higher up front cost.  

You can have all the charge sources you want, but have only one setup to do the equalization charge,  or buy charger from the same vendor that group charge.   



On Dec 23, 2014, at 11:16 AM, king_of_neworleans <no_reply@yahoogroups.com> wrote:

 

Micro inverters? Sounds interesting. Would they all be in phase with each other, feeding an AC bus? I have never heard of that. What would be the advantage of that? I guess you would have a lot more flexibility in laying out the panels...

Also since I am using flooded cell lead acid batts, I would really like to be able to give them an equalizing charge once in a while, without resorting to shore power. Is this possible? That would be 62v for a 48v bank.

So generally, with modern controllers, the set points are user programmable?

__._,_.___
Posted by: James Sizemore <james@deny.org>
Reply via web post • Reply to sender • Reply to group • Start a New Topic • Messages in this topic (6)

.

__,_._,___
Posted by at No comments:

[Electric Boats] FW: New Member from Iceland

 

Any feedback for this gentleman?

 

From: electricboats-owner@yahoogroups.com [mailto:electricboats-owner@yahoogroups.com] On Behalf Of Stefán Brandur Jónsson stefan@martolvan.is [electricboats]
Sent: Tuesday, December 23, 2014 9:11 AM
To: electricboats Moderator
Subject: Re: FILE - Welcome

 

Hi All 

 

I'm Stefan from Iceland, I'm an electronics field engineer by profession and bit of an boat and energy efficiency enthusiast.

My latest project is an feasibility / business plan for an catamaran tourist boat for using in my fjord that is for the most part very shallow, I think that an electric Jet drive would be the best fit where I need to overcome currents up to 8 knots in graceful manner. are there any ones that have some good advice on motor, battery and controller choices. My goal is to go electric only on approx hour trip on approx 25 KW load (max power 2 x 28 KW).

Look forward to comments.

 

2014-12-22 14:50 GMT+00:00 electricboats Moderator <electricboats-owner@yahoogroups.com>:


Welcome to the Electric Boat Club at Yahoo.
Feel free to introduce yourself to our membership by posting an email.
Do you currently own an electric boat?
Did you convert a boat to electric drive?
Are you interested in building or purchasing an e-boat?
Let us know.  Share your experiences---add links and photos of your project to our photos section.
We have over 1400 members and 6000 messages posted as of Jan, 2007.
There is much information in these past postings and the links are helpful.


Myles Twete, Portland, Or.
Moderator of Electric Boat Forum



 

--

Kveðja – Regards
Stefán B. Jónsson

Sími: +354-4781309 GSM: +354 8946541, skype: stefan.martolvan.is
Trúnaður /Disclosure

http://www.martolvan.is/tunadur-tolvuposts.html

__._,_.___
Posted by: "Myles Twete" <matwete@comcast.net>
Reply via web post • Reply to sender • Reply to group • Start a New Topic • Messages in this topic (1)

.

__,_._,___
Posted by at No comments:

Tuesday, December 23, 2014

Re: [Electric Boats] Multiple charging sources charging 48v bank?

 

Yeah that was helpful, Kevin.

I don't even need an inverter, tbh. I just want to charge a 48v battery bank.

Good suggestion on the Honda generator. I bet there are a few around that don't run, but still have a perfectly good generator. Simply a matter of making it play nicely with 48v. But since I have an extra 5kw BLDC motor I thought just while ago that I could use that, and a small controller that would basically operate the motor in regen mode, but could also provide a little kick start when needed, in low wind conditions. Of course it would take a pretty big turbine to work well with this motor... I am thinking about an 8 foot diameter swept area.

Some diy guys have used truck or bus alternators, or old 32v shrimp boat alternators, with a voltage divider feeding the regulator voltage.

I have no illusions of wind power giving me as much power as solar, but there are times (like 16 hours a day even when the sky is clear, and all the time when it is cloudy) when solar panels don't do anything useful. Some of that time, the wind is blowing, and even at my slip, I am just a few minutes from a 26 mile wide body of water with good anchor holding. I actually anticipate eventually spending more time anchored out than in the marina. So wind is a bit more potentially useful to me than for a dock queen.

Point taken on the MPPT. Looks like the only way to go for the solar side.

__._,_.___
Reply via web post • Reply to sender • Reply to group • Start a New Topic • Messages in this topic (4)

.

__,_._,___
Posted by at No comments:

Re: [Electric Boats] Multiple charging sources charging 48v bank?

 

Micro inverters? Sounds interesting. Would they all be in phase with each other, feeding an AC bus? I have never heard of that. What would be the advantage of that? I guess you would have a lot more flexibility in laying out the panels...

Also since I am using flooded cell lead acid batts, I would really like to be able to give them an equalizing charge once in a while, without resorting to shore power. Is this possible? That would be 62v for a 48v bank.

So generally, with modern controllers, the set points are user programmable?

__._,_.___
Reply via web post • Reply to sender • Reply to group • Start a New Topic • Messages in this topic (5)

.

__,_._,___
Posted by at No comments:

[Electric Boats] Re: Charging house and propulsion batteries

 

Wow - that e-mail must have travelled via the North Korean Internet. I
sent it on Dec. 14th (just went back to check my sent folder).

On 23/12/2014 3:39 AM, electricboats@yahoogroups.com wrote:
> 1a. Re: Charging house and propulsion batteries
> Posted by: "Darryl McMahon"darryl@econogics.com darryl_mcmahon
> Date: Mon Dec 22, 2014 6:40 am ((PST))
>
> In my experience with land-based EVs, a DC-DC converter would be used to
> step down the voltage from the propulsion pack to the accessory / house
> battery system.

<snip remainder original post>

__._,_.___
Posted by: Darryl McMahon <darryl@econogics.com>
Reply via web post • Reply to sender • Reply to group • Start a New Topic • Messages in this topic (8)

.

__,_._,___
Posted by at No comments:
Subscribe to: Posts (Atom)