Cruisers Forum
 


Join CruisersForum Today

Reply
 
Thread Tools Rate Thread Display Modes
Old 19-01-2013, 17:03   #1
Registered User
 
resilientg's Avatar

Join Date: Jul 2012
Location: Townsville, Qld, Australia
Boat: William Bollard, Gypsy Wave, 28'
Posts: 144
Additional Power What Would You Do in My Case?

Hi There,

It's starting to come into the cyclone season here so I'm going to have to adjust my current power setup to accommodate the possible high volume of overcast low power producing days.

Currently im totally self sufficient, i got 540 watts of solar, 480 amps AGM Deep Cycle and a 30 PWM Regulator. During normal sunny days i have heaps of surplus power that i cant collect as my bank is already fully topped up early in the morning

Ideally long term i would love to add 2 More 120 amp battery's, a MPPT regulator and a Big battery charger for whilst I'm marina bound in this period.

Problem is funds.

"So my question is", what would you do to boost the system right now if you had my system and had to choose between a new extra battery 120 a/h or a New MPPT Regulator, or a 25 amp Battery charger as there all around the same price?

Second set of questions would be "that if you choose the battery charger",

should i just get a small one to add power whilst the suns scarce as my solar system normal keeps my battery's fully charged, or should i get a big one say 25 amps to use to fully recondition my bank etc?

also as my boats steel I'm a bit dubious of the idea of keeping a battery charger on that much but have heard of marine chargers like the Ctek M series (M45, M100, M200, M300 etc) that are meant to have a circuit in them to stop my boat becoming hot from being plugged into shore power, so what do you think?

Thanks in advance to you all,

Matthew
__________________

__________________
Do but once what others say you cant, and you will never be judged by their limitations again.
resilientg is offline   Reply With Quote
Old 19-01-2013, 17:38   #2
Registered User
 
Jimbo485's Avatar

Join Date: May 2010
Location: some ocean down under
Boat: Kelsall Suncat 40
Posts: 1,247
Re: Additional Power What Would You Do in My Case?

Your choices are to increase:
1. Storage capacity.
2. Charging efficiency.
3. Storage capacity.

If you are worried about cloudy days in NQ, that means you need to increase your storage capacity, not your charging capacity, in order to get through the cloudy days. You said your batteries are typically fully charged by early morning, so that also confirms that you have plenty of charging capacity.

So buy a new battery, Matthew!
__________________

__________________

Jimbo485 is offline   Reply With Quote
Old 19-01-2013, 17:40   #3
Registered User
 
Jimbo485's Avatar

Join Date: May 2010
Location: some ocean down under
Boat: Kelsall Suncat 40
Posts: 1,247
Re: Additional Power What Would You Do in My Case?

Shoulda been ...


Your choices are to increase:
1. Storage capacity.
2. Charging efficiency.
3. Charging capacity.
__________________

Jimbo485 is offline   Reply With Quote
Old 19-01-2013, 19:22   #4
Marine Service Provider

Join Date: Oct 2007
Boat: Endeavour 42CC
Posts: 1,182
When it gets cloudy, doesn't it also get windy? Perhaps another choice comes to mind?
__________________
gettinthere is offline   Reply With Quote
Old 19-01-2013, 21:31   #5
Registered User
 
resilientg's Avatar

Join Date: Jul 2012
Location: Townsville, Qld, Australia
Boat: William Bollard, Gypsy Wave, 28'
Posts: 144
Re: Additional Power What Would You Do in My Case?

Quote:
Originally Posted by gettinthere View Post
When it gets cloudy, doesn't it also get windy? Perhaps another choice comes to mind?
I have a wind generator already, but as you never can determine the wind, i don't use it for calculations regarding power and only ever consider it as a "possible backup".

The sun on the other hand will come up every single day regardless, whether its hidden by clouds or not.

Hence my question and my choice of options.

Thanks anyway mate,

Matthew
__________________
Do but once what others say you cant, and you will never be judged by their limitations again.
resilientg is offline   Reply With Quote
Old 19-01-2013, 22:03   #6
Registered User

Join Date: Jul 2009
Location: Somewhere in the South Pacific
Boat: 1984 CS 36
Posts: 238
Re: Additional Power What Would You Do in My Case?

Quote:
Originally Posted by Jimbo485 View Post
Your choices are to increase:
1. Storage capacity.
2. Charging efficiency.
3. Storage capacity.

If you are worried about cloudy days in NQ, that means you need to increase your storage capacity, not your charging capacity, in order to get through the cloudy days. You said your batteries are typically fully charged by early morning, so that also confirms that you have plenty of charging capacity.

So buy a new battery, Matthew!
I'd conditionally disagree here. Our solar array is designed for "realistic" conditions - just because you're throwing away heaps of power when the sun's out doesn't mean that buying another panel won't make the difference on days with 50% sun or 25% sun, which might get you back to net neutral even during cyclone season.

It's a balance, of course - having 700% of your charging needs met so that you can charge on 100% cloud cover days would be a poor choice too. I'm just saying don't assume that another panel wouldn't help without first doing the math.
kb79 is offline   Reply With Quote
Old 19-01-2013, 22:06   #7
Senior Cruiser
 
maxingout's Avatar

Cruisers Forum Supporter

Join Date: Dec 2006
Location: Fort Pierce, Phoenix
Boat: Privilege 39 Catamaran, Exit Only
Posts: 2,606
Re: Additional Power What Would You Do in My Case?

Our Aerogen wind generators provided our most reliable power because we were in the trade winds. Our four solar panels were back up in case the wind failed us or there were engine problems.

You must have a massive solar panel array.
__________________
Dave -Sailing Vessel Exit Only

http://SailingUNI.com
http://maxingout.com
http://PositiveThinkingSailor.com
maxingout is offline   Reply With Quote
Old 19-01-2013, 22:53   #8
Registered User

Join Date: Jul 2009
Location: Somewhere in the South Pacific
Boat: 1984 CS 36
Posts: 238
Re: Additional Power What Would You Do in My Case?

Quote:
Originally Posted by maxingout View Post
Our Aerogen wind generators provided our most reliable power because we were in the trade winds. Our four solar panels were back up in case the wind failed us or there were engine problems.

You must have a massive solar panel array.
Here's the spec for an Aerogen wind generator:

http://shop.solar-wind.co.uk/acatalo...ine_Manual.pdf

I'm obviously not sure if that's yours or not, but looking at the picture of your boat, seems close. Let's assume that in the trades you're averaging 15 knots, 24 hours a day - looking at that curve, you'd be producing about 2.5A per generator, and it looks like you have two. That's 5A, 24 hours a day or 120Ah.

If found that our solar panels tend to (on a 12V system) produce on average about a third of their rated wattage in amp hours. E.G., our 380W array produces roughly 115Ah when averaged over say a typical month. In this case, Matthew said he has 540 watts of solar - if he has them mounted in a configuration that's roughly equivalent, I'd guess he's averaging about 160Ah a day - a good bit better than your 120. You didn't say how big your four solar panels are, but they may have been doing more of the lifting than you thought they were...

Just to be clear, I'm not arguing against wind, or even that 540W isn't a huge array - not trying to hijack the thread here in any way. Just emphasizing the fact that doing the math is worthwhile. The OP asked a question that probably has an actual objective answer when balancing storage vs. production vs. dollars.

Bust out the calculator, read the specs for all the different options, calculate the boat's load, the output realized from the current solar array, etc. and figure out what solves the problem in the most efficient way.
kb79 is offline   Reply With Quote
Old 19-01-2013, 23:29   #9
Registered User

Join Date: Jul 2009
Location: Somewhere in the South Pacific
Boat: 1984 CS 36
Posts: 238
Re: Additional Power What Would You Do in My Case?

Quote:
Originally Posted by resilientg View Post

....

Second set of questions would be "that if you choose the battery charger",

should i just get a small one to add power whilst the suns scarce as my solar system normal keeps my battery's fully charged, or should i get a big one say 25 amps to use to fully recondition my bank etc?
If you go this route, get the small charger. Your batteries don't need to be equalized all that often (especially if they're kept full), and you'll be able to easily do that on sunny days with the solar array you have.
kb79 is offline   Reply With Quote
Old 20-01-2013, 05:46   #10
Registered User
 
Jimbo485's Avatar

Join Date: May 2010
Location: some ocean down under
Boat: Kelsall Suncat 40
Posts: 1,247
Re: Additional Power What Would You Do in My Case?

He FULLY charges his batteries with his current solar array by "early in the morning". The OP's words.

No more charging capacity or charging efficiency is needed, BASED ON HIS CURRENT SITUATION.

So the solution, based on his clearly declared three alternatives, is very obvious.
__________________

Jimbo485 is offline   Reply With Quote
Old 20-01-2013, 05:56   #11
Moderator
 
noelex 77's Avatar

Cruisers Forum Supporter

Join Date: Jul 2007
Location: Living on dirt waiting for our new yacht to be built.
Boat: Half built Bestevaer.
Posts: 10,618
Re: Additional Power What Would You Do in My Case?

Adding a new battery to existing battery bank can create problems, so this option is best considered when you whole battery bank needs replacing.
Switching from a good Non MPPT regulator, to MPPT will only give you a small gain 5-10%.
That leaves the battery charger. It's difficult to gauge the value of this without knowing how often you have access to shore power.
I only get shore power every couple of years so my battery charger contributes very little, but for most people this would be the most sensible option of the 3.
__________________
noelex 77 is offline   Reply With Quote
Old 20-01-2013, 08:17   #12
Senior Cruiser
 
maxingout's Avatar

Cruisers Forum Supporter

Join Date: Dec 2006
Location: Fort Pierce, Phoenix
Boat: Privilege 39 Catamaran, Exit Only
Posts: 2,606
Re: Additional Power What Would You Do in My Case?

Quote:
Originally Posted by kb79 View Post
Here's the spec for an Aerogen wind generator:

http://shop.solar-wind.co.uk/acatalo...ine_Manual.pdf

I'm obviously not sure if that's yours or not, but looking at the picture of your boat, seems close. Let's assume that in the trades you're averaging 15 knots, 24 hours a day - looking at that curve, you'd be producing about 2.5A per generator, and it looks like you have two. That's 5A, 24 hours a day or 120Ah.

If found that our solar panels tend to (on a 12V system) produce on average about a third of their rated wattage in amp hours. E.G., our 380W array produces roughly 115Ah when averaged over say a typical month. In this case, Matthew said he has 540 watts of solar - if he has them mounted in a configuration that's roughly equivalent, I'd guess he's averaging about 160Ah a day - a good bit better than your 120. You didn't say how big your four solar panels are, but they may have been doing more of the lifting than you thought they were...

Just to be clear, I'm not arguing against wind, or even that 540W isn't a huge array - not trying to hijack the thread here in any way. Just emphasizing the fact that doing the math is worthwhile. The OP asked a question that probably has an actual objective answer when balancing storage vs. production vs. dollars.

Bust out the calculator, read the specs for all the different options, calculate the boat's load, the output realized from the current solar array, etc. and figure out what solves the problem in the most efficient way.
I installed my first Aerogen 6 in windy New Caledonia, and I did not have to run my engine for three weeks because the trade winds were providing 200 amp hours of power a day. I was extemely happy to not need to run my engine at all for those three weeks. At that point I decided to install a second one because I was going to complete my circumnavigation with four heavy users of everything electrical on board our catamaran. I also converted from an engine driven compressor for refrigeration to an electrical compressor since I had more electricity. The two Aerogen 6 generators gave me 400 amp hours of electricity as long as I was in the trade winds. I love the trades.

Your mileage may differ, but it worked awesome for me as long as I was in the trades.
__________________
Dave -Sailing Vessel Exit Only

http://SailingUNI.com
http://maxingout.com
http://PositiveThinkingSailor.com
maxingout is offline   Reply With Quote
Old 20-01-2013, 10:09   #13
Registered User

Join Date: Jul 2009
Location: Somewhere in the South Pacific
Boat: 1984 CS 36
Posts: 238
Re: Additional Power What Would You Do in My Case?

Quote:
Originally Posted by Jimbo485 View Post
He FULLY charges his batteries with his current solar array by "early in the morning". The OP's words.

No more charging capacity or charging efficiency is needed, BASED ON HIS CURRENT SITUATION.

So the solution, based on his clearly declared three alternatives, is very obvious.
That may or may not be true. I'm not sure what things are like in Townsville, but we were just in Brisbane, and the sunrise is ungodly early - our array was pumping by 7AM. It's just a weird time zone, and they don't do daylight savings. So, being charged "early" could be a function of the fact that sunrise is literally at 4AM.

More importantly though, the performance of the array on a sunny day isn't necessarily the point. An additional panel might make the difference. Or, it might not. He should do that calculation is all I'm saying, and not just assume that another panel isn't worth considering.

We cruised with a 35' boat that had 620W of solar. He was sized such that he'd fully charge on 75% cloudy days, and it worked well.
kb79 is offline   Reply With Quote
Old 20-01-2013, 10:12   #14
Registered User

Join Date: Jul 2009
Location: Somewhere in the South Pacific
Boat: 1984 CS 36
Posts: 238
Re: Additional Power What Would You Do in My Case?

Quote:
Originally Posted by maxingout View Post
I installed my first Aerogen 6 in windy New Caledonia, and I did not have to run my engine for three weeks because the trade winds were providing 200 amp hours of power a day. I was extemely happy to not need to run my engine at all for those three weeks. At that point I decided to install a second one because I was going to complete my circumnavigation with four heavy users of everything electrical on board our catamaran. I also converted from an engine driven compressor for refrigeration to an electrical compressor since I had more electricity. The two Aerogen 6 generators gave me 400 amp hours of electricity as long as I was in the trade winds. I love the trades.

Your mileage may differ, but it worked awesome for me as long as I was in the trades.
I stand corrected. The Aerogen 6 looks much more efficient at lower wind speeds. Here's the spec:

http://www.idl.ku.edu/ARA/AARPS/Docu...gen_manual.pdf

200Ah with good wind seems reasonable.
kb79 is offline   Reply With Quote
Old 21-01-2013, 04:44   #15
Registered User

Join Date: Mar 2012
Location: On board in Alanya, Turkey
Boat: Hunter Legend 420 Passage
Posts: 626
Re: Additional Power What Would You Do in My Case?

Quote:
Originally Posted by resilientg View Post
.......... if you had my system and had to choose between a new extra battery 120 a/h or a New MPPT Regulator, or a 25 amp Battery charger as there all around the same price?
A new extra battery: As Noelex 77 says don't add old to new. Make it much bigger next time.

A new MPPT regulator: This would be be my suggestions as they say it should give an increase in power on cloudy days. BUT get a proper - expensive one - and one that you can program to suit your system and battery capacity. You say - like many - that your batteries are 100% topped up in the morning. This is very unlikely to be true as all regulators switch to float too early to avoid overcharging. Is quite possible they are only at 90% charged. That's 20% down on your useable capacity from 50-100%. One parameter you might need to change is the absorption time so that just before it does go to float the current going in is close to the 0.5% of your bank capacity. You can check how your system is working by disconnecting the solar panels when it has just gone to float and see how much the current increases when the regulator goes back to absorption mode. If this is considerable then the batteries are not 100% charged. Check out the Morningstar MSView software that allows you to adjust about a dozen settings to make your setup work more efficiently. Only play with this if you are confident to make the adjustments, if not get a qualified marine electrical engineer to do it.

A 25 AMP battery charger:
You want a big one, especially for AGMs, go for 120 amps to guarantee they are fully charged if you arrive at a marina at 2000 hrs and leave the next morning at 0800 hrs.
__________________

__________________
sailinglegend is online now   Reply With Quote
Reply

Thread Tools
Display Modes Rate This Thread
Rate This Thread:

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off




Copyright 2002- Social Knowledge, LLC All Rights Reserved.

All times are GMT -7. The time now is 01:11.


Google+
Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2017, vBulletin Solutions, Inc.
Social Knowledge Networks
Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2017, vBulletin Solutions, Inc.

ShowCase vBulletin Plugins by Drive Thru Online, Inc.