High Output Alternators

[sailinglegend]

Originally Posted by Maine Sail

The only things I can figure on consuming 225 ah's in 24 hours are;

1- He's running a gourmet kitchen/galley with a Sub Zero household refrigerator and then running it through an inverter.

2- His math is off

We take 10-15 amps when sailing - that is on a bad weather day without solar, or the solar is totally shaded by the sails, and without using our DuoGen towing generator. That's 240-360 Ahs/day. Deduct 60 AH for the fridge only working half the time and another 60 Ah for the Autopilot not working flat out all the time and any cruiser can easily get to 225 Ahs/day.

We have the Radar on standby most of the time and all the usual power saving devices like LEDs. We often switch the Autopilot response down from 5 to 3 to save power, but we have set up our system for the worse case scenario of 250 Ah/day. With our 1050 Ah bank we can sail continually for 48 hours without charging.

In practice - in the real world - when the sun is shining and the DuoGen towing generator working we arrive at our destination with more Ahs in our batteries then when we started.

In some of your recent post Maine Sail you have been talking a lot about batteries etc. and how they perform - in the real world. We all really appreciate those articles buy have you just exposed your weakness about how serious cruisers cruise. Perhaps you need to get out of the marina for more than just a weekend and see just how many Ahs some cruisers can use.

It is often too easy for too many people on this generally excellent forum to make too many comments that are generally too general!

[Maine Sail]

Originally Posted by sailinglegend

We take 10-15 amps when sailing - that is on a bad weather day without solar, or the solar is totally shaded by the sails, and without using our DuoGen towing generator. That's 240-360 Ahs/day. Deduct 60 AH for the fridge only working half the time and another 60 Ah for the Autopilot not working flat out all the time and any cruiser can easily get to 225 Ahs/day.

We have the Radar on standby most of the time and all the usual power saving devices like LEDs. We often switch the Autopilot response down from 5 to 3 to save power, but we have set up our system for the worse case scenario of 250 Ah/day. With our 1050 Ah bank we can sail continually for 48 hours without charging.

In practice - in the real world - when the sun is shining and the DuoGen towing generator working we arrive at our destination with more Ahs in our batteries then when we started.

In some of your recent post Maine Sail you have been talking a lot about batteries etc. and how they perform - in the real world. We all really appreciate those articles buy have you just exposed your weakness about how serious cruisers cruise. Perhaps you need to get out of the marina for more than just a weekend and see just how many Ahs some cruisers can use.

It is often too easy for too many people on this generally excellent forum to make too many comments that are generally too general!

I have plenty of "real" cruising boats I work on and am far from just a guy who works on "marina queens" many of my summer time customers are off cruising right now with well managed systems.. I fully uderstand cruisers needs are all different.

That comment was based on a response to him needing more than a 100A alternator and in a "joking" fashion hence the winkie. We do joke here on occasion...

I made my post tongue in cheek based on the evidence on hand at the time and, in hindsight, probably should not have. I would be quite curious for Cutterman to tell us his actual net measured daily averages though.

It was also loosely based in response to the fact that Cutterman stated he already had solar (355W), was going to add a wind and a water generator. There is absolutely nothing wrong with sizing for a worst case, and I would in-fact advise that if it suits the wallet and your comfort level.

Originally Posted by Cutterman

I have 3 x 75W and 2 x 65W solar panels and plan to buy an Airbreeze and a used wind/water generator which should be sufficient to drive the fridge/freezer a lot of the time.

And of course you stated you've sized for 250Ah day but then say;

Originally Posted by sailinglegend

In practice - in the real world - when the sun is shining and the DuoGen towing generator working we arrive at our destination with more Ahs in our batteries then when we started.

My statement, as I said, was loosely based on "real world" experiences, as your statement above was. You just finsihed telling us how you're sized for 250Ah's a day then tell us how in the "real world" you arrive with more Ah's then you set out with. That is also where my post came from based on Cutterman's own statements about solar, wind and adding a water gen....

What I see my cruising customers use who have both solar and wind on a daily Ah basis varies widely. I have some who use well under 40Ah's a day net while at sea and others who use considerably more even with solar and wind. Can max worst case system design happen, of course. With both solar and wind it's not going to be an every day occurrence. Sometimes designing a system around an occasional occurrence can get steep price wise, eat into space, especially on a 33 footer, and the cost factor of drawing the bank to 80% DOD, on occasion, has to be examined against the cost of additional equipment, customizing etc. etc. etc... Some people choose to always size for worst case and if the wallet is happy that is all that matters..

Beyond that our own boat "cruised" for 5 years 24/7 with 95% of the time spent on the hook. I guess this is not "serious" enough cruising for you???

She did so with a single 80W panel and stock 50A alternator. She was cruised with energy conservation and used engine driven refrigeration. Every cruiser has their own consumptions but both are "serious cruisers".

Cutterman, I apologize for my response if it was taken as anything but in good humor and loosely based on what you told us you had and were adding for energy production.. If you get a chance I'd love to know your average daily "net" Ah use with your new system in place....

sailinglegend, I find your attempt at a personal level dig / insult to me both uncalled for and immature... I would expect better. I have been polite to you....

[foggysail]

Originally Posted by Maine Sail

sailinglegend, I find your attempt at a personal level dig / insult to me both uncalled for and immature... I would expect better. I have been polite to you....

AMEN!!!

[sailinglegend]

Originally Posted by Maine Sail

..........sailinglegend, I find your attempt at a personal level dig / insult to me both uncalled for and immature... I would expect better. I have been polite to you....

I apologize, but I was trying to make the point that 225 Ah/day is not out of the ordinary. Your post clearly suggested it was.

I hope some of the readers here take the opportunity to actually measure - not guesstimate - their actual daily usage. We did this the other week sitting in the marina for 24 hours by disconnecting all charging sources and reading the Ah discharged from a well set-up Battery Monitor. Over three days ours averaged 60Ah each night from 2000 hrs to 0800 hrs. We checked one day from 0800 - 2000 hrs and it was about the same.

[Vasco]

Originally Posted by sailinglegend

I hope some of the readers here take the opportunity to actually measure - not guesstimate - their actual daily usage. We did this the other week sitting in the marina for 24 hours by disconnecting all charging sources and reading the Ah discharged from a well set-up Battery Monitor. .

Most cruisers have a very good idea what their daily usage is. That's because they're not sitting in a marina, plugged into shore power.

[Cheechako]

At anchor 225 would have been out of the ordinary for me on 44-47 footers. More like 125 most days, including an hour or two of TV, refrigeration, a couple minutes of micrwave, paktor use and the usual other stuff.

[DevoDave]

Originally Posted by sailinglegend

It is often too easy for too many people on this generally excellent forum to make too many comments that are generally too general!

Lol.

[Cheechako]

Originally Posted by DevoDave

Lol.

I think that's true.... generally....

[Cutterman]

Some other factors to be considered:

• My cruising regime usually involves being under way about 35% of the time. This may change, of course, but it is when I use the most energy and can usually harvest the most naturally available power. I aim to keep within the top 25-30% of battery capacity. My AGM batteries need to reach full charge regularly to remain healthy and last. Hence my interest in multiple charging methods.

• I will purchase a DuoGen only if I think I should when I have fully tested my new system in the tropics in a couple of years time.

• The weak link in my system is the limit to my battery capacity. I will not increase it for weight and space reasons. If I find 450 Ahrs plus starting, water making and anchor winching inadequate, I can either up the size of one alternator from 70 to 100 Ahrs (it has a half inch belt drive) and/or use a Duogen even when at anchor since I will often stop in places where the tide runs at 3 knots plus.

• Maine Sail, apology accepted although a bit of levity once in a while does not really justify one.

• Life is like a toilet roll. The nearer you get to the end, the faster it seems to be running and out.

Seasons greeting to you all!

[Maine Sail]

Originally Posted by Cutterman

I aim to keep within the top 25-30% of battery capacity. My AGM batteries need to reach full charge regularly to remain healthy and last. Hence my interest in multiple charging methods.

Yes AGM's do best when topped to full as often as possible and with roughly 2/3 time, not sailing, your solar, wind and alts should likely be able to handle this need. The big question still remains what are the "average" daily nets to the bank.. Without accurately knowing this it is really difficult to design for the optimum solutions.

Originally Posted by Cutterman

• I will purchase a DuoGen only if I think I should when I have fully tested my new system in the tropics in a couple of years time.

What are you using to track Ah consumption and charging system performance? Do you have a battery monitor/Ah counter?

Originally Posted by Cutterman

• The weak link in my system is the limit to my battery capacity. I will not increase it for weight and space reasons. If I find 450 Ahrs plus starting, water making and anchor winching inadequate, I can either up the size of one alternator from 70 to 100 Ahrs (it has a half inch belt drive) and/or use a Duogen even when at anchor since I will often stop in places where the tide runs at 3 knots plus.

A bigger alt will help change your bulk charge speed/time. This can be good however as your AGM's can accept it. The alts wont do much in the top 10-15% SOC range as acceptance will likely have them limited below full potential but they will speed bulk charging when you go below 80-90% SOC. If trying to keep DOD to 70-75% SOC your extra alt capacity would see less benefit as "bulk" time would still be rather short before hitting absorption voltage.. Bulk would still be shorter though..

There are now serpentine pulley kits available for the Volvo MD-2030. These pulleys allow you to drive significantly more current with a single belt... I helped a company in Canada develop that specific kit last spring. You may not be limited to a 1/2" belt. If you find you are regularly needing to replace 200+ Ah then a kit like this may make sense.

This is what that kit looks like on a MD-2030.

[Jim Cate]

FWIW,

Here's another anecdotal observation:

We have seen some half dozen boats with duo gen systems on board out here cruising in the southwest Pacific. EVERY ONE of them was out of service, and the owners were pissed off.

This is not a statistically relevant sample, but it would scare me away from buying one!

Cheers,

Jim

[Amnesia II]

I finally feel I'm on the right track with my new 800AH AGM batt bank, 200amp Electromaxx alt with serpentine belt (as per Mainsails photo). Just added 400W solar ( another 200W optional).

Lots of power variables, plus and minus creep in so I think I'm now in a position to maintain batts well topped up and healthy with minimal engine running.

I do only have the basic reg supplied with the Electromaxx, would you advise a more "smart" regulator, Mainsail?

[downunder]

Also Mainsail how do you find the Electromaxx alternator fitted to that serpentine belt??

Thanks

[Amnesia II]

Downunder, I can answer that one I for you I think....Electromaxx market the whole bundle as a complete kit....high output alt, reg, pully & belt ( to fit straight on to various motors).
Do check their website for details.

[Maine Sail]

Originally Posted by downunder

Also Mainsail how do you find the Electromaxx alternator fitted to that serpentine belt??

Thanks

Does exactly what it is advertised to do. I was just on that boat a few weeks ago and after 150 engine hours there was not a spec of belt dust anywhere...

That particular alt feeds a 400Ah bank of Odyssey PC2150's and will produce 125 - 130A for over an hour and not go into temp limiting. It runs cool and damn near its rating even when "hot".. It is a 140A alt.. There are many good alts out there I just happen to like the whole kit they offer.

I also install Balmar and have custom alts built for me, just depends upon the project. I obviously make more money when I sell my own alts but sometimes the 130D case style works and fits better. With the dual internal fans they also cool very well in small tight spaces..

I don't use their reg though and install them with a Balmar MC-614. Really this is a beefed up 130D Delco with larger bearings and custom castings for the case etc. etc...