T-Pain Is On A Boat: December 2024

Sunday, December 8, 2024

Re: [electricboats] Complex design issues

Check you math. All panels in series as in 6S for 16V/7A panels is 96/7, not 96/14.

On 2024-12-08 9:55 am, Dale Shomette via groups.io wrote:

So Jeff, you have two sets of three panels, each three panels in series and each three panels with their own controllers. You believe they are 16volt/7amp panels, correct? So in series, the maximum voltage from your three panels would be 48 volts and seven amps.

Together, the six panels (as individual sets of three) would theoretically pull out 96 volts and 14 amps. Are your Victron controllers charging your batteries individually? Why do you need two Victron 150/35's when one would handle both sets of three panels? Why not put each two of the six panels in series with each other, then put the six in parallel. Wouldn't that give you a maximum of 48 volts and an increase to up to 21amps to your battery bank? Of course, I have no idea how big your battery bank is and 48 volts might not do it for you. I will need a minimum of 54 volts for each of my four battery banks but will be charging them individually. I think your Victron 150/35 would be perfect to do that but was thinking that at full charge of a bank, I would just switch over from that bank to the other and only need the one controller. Is that reasoning sound from your perspective? By the way, what is your average collective sunlight day where you are?

Thanks Again,

Dale

On Thu, Dec 5, 2024 at 10:32 PM jeffsschwartz via groups.io <jeffsschwartz=hotmail.com@groups.io> wrote:

Hi Dale,

It's been a few years since I picked them up but I believe they're 16V/7A. I have 6 of them so I wire 3 in series and then the output from the 3 into the MPPT controller, then repeat for the second controller. When I look at the output from the panels on the Victron app on my cell, I'm seeing around 54V go into the batteries per controller. I've never seen the total current from both controllers go about 3A even on the sunniest of days.

On a mid summer, no cloud day, I'll get a total charge of around 2 KW between the two controllers. That may partially be due to panel placement, my boat's on a 3 point mooring facing south so the angles are not optimal.

Regards,

Jeff.

Re: [electricboats] Complex design issues

So Jeff, you have two sets of three panels, each three panels in series and each three panels with their own controllers. You believe they are 16volt/7amp panels, correct? So in series, the maximum voltage from your three panels would be 48 volts and seven amps.

Together, the six panels (as individual sets of three) would theoretically pull out 96 volts and 14 amps. Are your Victron controllers charging your batteries individually? Why do you need two Victron 150/35's when one would handle both sets of three panels? Why not put each two of the six panels in series with each other, then put the six in parallel. Wouldn't that give you a maximum of 48 volts and an increase to up to 21amps to your battery bank? Of course, I have no idea how big your battery bank is and 48 volts might not do it for you. I will need a minimum of 54 volts for each of my four battery banks but will be charging them individually. I think your Victron 150/35 would be perfect to do that but was thinking that at full charge of a bank, I would just switch over from that bank to the other and only need the one controller. Is that reasoning sound from your perspective? By the way, what is your average collective sunlight day where you are?

Thanks Again,

Dale

On Thu, Dec 5, 2024 at 10:32 PM jeffsschwartz via groups.io <jeffsschwartz=hotmail.com@groups.io> wrote:

Hi Dale,

It's been a few years since I picked them up but I believe they're 16V/7A. I have 6 of them so I wire 3 in series and then the output from the 3 into the MPPT controller, then repeat for the second controller. When I look at the output from the panels on the Victron app on my cell, I'm seeing around 54V go into the batteries per controller. I've never seen the total current from both controllers go about 3A even on the sunniest of days.

On a mid summer, no cloud day, I'll get a total charge of around 2 KW between the two controllers. That may partially be due to panel placement, my boat's on a 3 point mooring facing south so the angles are not optimal.

Regards,

Jeff.

_._,_._,_

Groups.io Links:

You receive all messages sent to this group.

_._,_._,_

Thursday, December 5, 2024

Re: [electricboats] Complex design issues

Hi Dale,

It's been a few years since I picked them up but I believe they're 16V/7A. I have 6 of them so I wire 3 in series and then the output from the 3 into the MPPT controller, then repeat for the second controller. When I look at the output from the panels on the Victron app on my cell, I'm seeing around 54V go into the batteries per controller. I've never seen the total current from both controllers go about 3A even on the sunniest of days.

On a mid summer, no cloud day, I'll get a total charge of around 2 KW between the two controllers. That may partially be due to panel placement, my boat's on a 3 point mooring facing south so the angles are not optimal.

Regards,

Jeff.

_._,_._,_

Groups.io Links:

You receive all messages sent to this group.

_._,_._,_

Re: [electricboats] Complex design issues

Jeff, what's the volt and amperage rating on your panels? Why use three controllers, one for each panel?

On Thu, Dec 5, 2024 at 3:15 PM Dale Shomette via groups.io <dashoway=gmail.com@groups.io> wrote:

Thanks Jeff. I'm taking a look at Victron now.

On Mon, Dec 2, 2024 at 10:46 PM jeffsschwartz via groups.io <jeffsschwartz=hotmail.com@groups.io> wrote:
I'm using Victron MPT 150/35 charge controllers on each of my 3 panels that are in series and it has no issue evening out the voltage. It has a rotary switch that lets you set the charge profile depending on the battery chemistry. I don't think it converts excess voltage to current (probably just regulates it down to the correct level) but it has never damaged the batteries during charging.

_._,_._,_

Groups.io Links:

You receive all messages sent to this group.

_._,_._,_

Re: [electricboats] Complex design issues

Thanks Jeff. I'm taking a look at Victron now.

On Mon, Dec 2, 2024 at 10:46 PM jeffsschwartz via groups.io <jeffsschwartz=hotmail.com@groups.io> wrote:

I'm using Victron MPT 150/35 charge controllers on each of my 3 panels that are in series and it has no issue evening out the voltage. It has a rotary switch that lets you set the charge profile depending on the battery chemistry. I don't think it converts excess voltage to current (probably just regulates it down to the correct level) but it has never damaged the batteries during charging.

_._,_._,_

Groups.io Links:

You receive all messages sent to this group.

_._,_._,_

Wednesday, December 4, 2024

Re: [electricboats] Complex design issues

On solar cells in series vs parallel: If all things were equal, series strings would not be preferred, specifically because of the direct effect that shading a single cell in the string has to the output. It's a huge price to pay---just a splat of seagull poop on one cell that drops its output to 40% will drop the entire string's maximum current output to 40% as I see it.

So, ideally, solar panels would parallel ALL of the cells to eliminate this huge penalty. The reason panels are not made this way is because of the very low voltage (around 0.58v Voc) put out by a cell. Boost converters just can't boost this low voltage up to 12v efficiently, so cells are put in series on panels. And so some of the earliest panels put out maybe Voc~18v and today's panels, with 32-96 cells have Voc from 20v to around 60v.

Now, to reduce the shading penalty, solar panel manufacturers often (always?) include some number of Germanium bypass diodes such that that panel's output will drop in voltage but can still deliver an optimal high current. It's been suggested to use panels with at least 3 such diodes.

But let's say you have panels on port and panels to the starboard. It might make best sense to put the port panels in series, same with the starboard ones and then either parallel up the 2 strings and connect to the MPPT controller or send each string's output separately to a converter.

It helps to think about lithium battery configurations for EVs these days. It used to be (when most EVs on the road were DIY---i.e. pre-2000) that no one recommending paralleling battery cells or batteries due to risks involved. You'd see some folks paralleling up strings and others paralleling up 12v batteries, usually without incident. Even with lithium based EV packs, we saw in 2010-11 cars being produced with 2 parallel strings of 96 cells. And EACH of those cells in each string needed a cell voltage manager. Tesla went a different direction. They realized that if they massively paralleled the cells as much as possible, then they could avoid multiple series strings, multiple BMS, etc. Sure, there's risk that a single or leaky shorted cell will cause major issues, but they took that risk.

Back to solar cells---paralleling cells does not bring any real risk. Each cell itself is actually made up of a lot of silicon in parallel. For a boat, with possibility of mast, humans and other objects obscuring part or all of several cells, it seems that the best solution would be massive parallelization of cells. And yet, at some point you need that pack voltage and so ultimately cells need to be put in series.

-mt

Re: [electricboats] Complex design issues

I don't understand where your coming up with 22 to 33.3 Amps (OK I think I do, but I also think you are doing it wrong).

It's all about the Watts. Watts is power, Watt/hrs are storage (simplified I know).

Look at it this way, you have 8ea 100 Watt panels, so a max total possible input of 800 Watts.

If you divide 800W by 48V, you get 16.66 Amps, and 800/72 = 11.11 Amps. But whatever Voltage your panels are putting out, the max Wattage is still 800.

So for me, I look at Watts needed for a given speed and then Watt/hrs left in my pack, to determine how far I can go.

Another thing to think about is power loss to conversion/heat. In your example using the theoretical max of your solar panels of 800W, your going to loose a little at the controller (The Victron 100/20/48V claims 98% conversion efficiency) so 800x0.98=784. So now your only getting 784W to the battery (assuming no voltage drop from the wires, and there are ALWAYS voltage drop from wires). There is also some loss at the battery itself.

I can tell you from experience that putting 100W into a battery for an hour does not net you a 100W/hr charge. I have Watt/hr meters at my batteries that count up from zero when using, and back down when charging. When fully charged the count will always be negative (until I zero them). As far as I can tell, my battery loss is around at least 0.5% (small but still relevant). So now you are down to about 780W.

If you add in the fact that you will also never see the full 100W / panel (unless you are in laboratory conditions) you should always factor in some loss before hand, then later measure when your system is operating.

You should also be careful when having 2 different batteries that you use independently. You would need to turn the discharged (used) battery off before turning on the charged (un-used) battery. If you connect two batteries with different voltages together, you will probably see some smoke, and need some new wires (unless you have the fuses and circuit breakers needed). This is just a guess of course, because I have never, ever, ever, ever, ever, done such a thing (did I protest too much?).

And you would also need to separate the charging system from each battery.

I have my battery banks hooked up to bus bars and use them all at the same time. The solar and shore power chargers AND ALL loads are also connected to these bus bars. The solar charge converters are always on so when the sun is shining all the solar power is being used first. If the batteries are full and the load is small, the solar controllers limit the output to just enough to run the load. If the load increases then the controllers increases the output to match until the load becomes more than the solar is providing (or a cloud passes over) then the load starts drawing from the battery, but only for the excess load above what the controllers are providing.

Then if the load decreases back below the controllers output the excess power from the controllers charge the battery.

So in your case I would recommend using both batteries until 2/3 discharged, then fire up the generator and charge them back up (boating best practices: 1/3 on the way out, 1/3 for on the way back in and 1/3 in reserve for emergencies).

But as always, it's your boat, do it however makes you happy.

_._,_._,_

Groups.io Links:

You receive all messages sent to this group.

_._,_._,_

Re: [electricboats] Complex design issues

Yes, two strings of 4 panels is the way to go. Each to its own controller.

I'm also using a MPPT controller to charge my 12V system from the 48V bank. In my case a 100/15 as I had it on hand. It occurs to me, one could use a 100/20 to charge to 48V system from the 12V system if the need arises. Although I've not tried that yet.

On Thu, 5 Dec 2024, 07:19 kurtphone via groups.io, <kurtphone=gmail.com@groups.io> wrote:

I have 8 x 100 watt flex panels charging my 48 volt battery bank with 2 x Victron 100/20 48 volt MPPT solar controllers. I think you will be much better off with 4 panels in series to each controller and then parallel the controllers.
I run the solar banks port and starboard so most shading degradation only affects one or the other solar bank at a time. A shadow on all or part of any panel drops the output of the whole series string.

Slightly off topic…I am using a left over 12 volt smart solar controller as a DC-DC converter for charging my house bank from the traction bank. Charge parameters can be monitored and controlled with the Victron IPhone app. This works really nicely.

Remember….no welding!

_._,_._,_

Groups.io Links:

You receive all messages sent to this group.

_._,_._,_

Re: [electricboats] Complex design issues

I have 8 x 100 watt flex panels charging my 48 volt battery bank with 2 x Victron 100/20 48 volt MPPT solar controllers. I think you will be much better off with 4 panels in series to each controller and then parallel the controllers.
I run the solar banks port and starboard so most shading degradation only affects one or the other solar bank at a time. A shadow on all or part of any panel drops the output of the whole series string.

Slightly off topic…I am using a left over 12 volt smart solar controller as a DC-DC converter for charging my house bank from the traction bank. Charge parameters can be monitored and controlled with the Victron IPhone app. This works really nicely.

Remember….no welding!

_._,_._,_

Groups.io Links:

You receive all messages sent to this group.

_._,_._,_

Tuesday, December 3, 2024

Re: [electricboats] Complex design issues

Thanks for the response. You noted that I had two strings of four panels, which I do, but they would be pairs in series & parallel with each :-|____|+........ -|___|+: other

:-|____|+........ -|___|+:

:-|____|+.........-|___|+:

: ..........batteries....... :

Each panel of 100 watts, configured together, going from 12-18 volts depending on the sun, producing 48 to 72 volts and 22 to 33.3 amps, being controlled by your Victron MPT 150 volt / 35 amp, seems like it would be what I need to charge one four battery bank of batteries that are configured to provide 48 volts to the Electric Yacht 2.0 single or tandem drive motors. Using bank #1 of 185amps THEORETICALLY using 40% of that power (74 amps) would drive my boat @3.5knots for about two hours and almost an hour longer if the 22.22 additional amps are added in each hour(assuming the voltage is @18 volts/panel), then switch over to the fully charged bank#2 with the same treatment for another two to three hours. Again, ALL THEORETICAL. Every few hours, I can run the 48 volt gen.set to fully charge the first bank again. The 10k gen.set can put out 208 amps @ 48 volts which can run the Electric Yacht 2.0 to travel @ 6.1knots through the battery banks or directly. With both gen sets online, the hull speed of 7.1 knots, requiring 330 amps, 48 volts, 15,840 watts is THEORETICALLY do-able. THAT though, is why the boat is a hybrid. I like the quiet of a sailboat in motion that the electric motors provide, however, at the same time the gen sets, at only 60 decibels are not nearly as noisy as a big engine chuggin' along. These are clean and quiet and with two, redundant.

I've had the gen sets on another boat that had 4 thru the hull pod motors. It was a 38' boat. that boat had no solar panels but it had 24 batteries in three separate banks. It was a prototype and out of Cambridge, Md., we did a shakedown cruise of about 25 miles @6.3 knots on one battery bank of 8 185 amp/hr. batteries. At 70%, one of the gen sets was supposed to come on, but it didn't. When we got back the bank was down to almost 60%. We started a gen set and in about two hours the bank was fully charged. The generator had used only two liters of fuel! If you extrapolate the distance traveled and the weight of a 38 foot cyprus built wooden boat, that is an efficiency that started me down this path. The same trip with a diesel would have consumed several GALLONS of fuel. Both gen sets are still new....except one of them has two hours on it. This project is the whole enchilada. Wind turbine forward, solar panels on the cabin and cockpit roof. My plan is to do it right but try to get it done before I die....which I'm trying to avoid for a while. I apologize going far afield here but it has become a bit of a passion that I recognize I can't do it all nor know it all. That's why I appreciate the knowledge and input of you guys. Having a Nigel Calder for a neighbor might have helped too!

_._,_._,_

Groups.io Links:

You receive all messages sent to this group.

_._,_._,_

Re: [electricboats] Complex design issues

"Both Genasun and Renogy make MPPT controllers that step up for 48V batteries. Genasun being much the preferred brand."

Thanks Paul, very good info there.

I had never heard of Genasun.

Those Genasun Boost converters look very good, claim to be 99% efficient, and long as you buy the correct one for your set-up, you don't have to set anything.

_._,_._,_

Groups.io Links:

You receive all messages sent to this group.

_._,_._,_

Re: [electricboats] Complex design issues

I have no skin in this game at the moment, but I sure appreciate this
type of explanation.

-=-=-=-=-=-=-=-=-=-=-=-
Groups.io Links: You receive all messages sent to this group.
View/Reply Online (#32798): https://groups.io/g/electricboats/message/32798
Mute This Topic: https://groups.io/mt/109836164/3360820
Group Owner: electricboats+owner@groups.io
Unsubscribe: https://groups.io/g/electricboats/leave/6293187/3360820/430022002/xyzzy [newarmyguitar24@gmail.com]
-=-=-=-=-=-=-=-=-=-=-=-

Re: [electricboats] Complex design issues

" I don't know of any SOLAR battery charger/converters that will step up AND down. They might be out there somewhere, but I don't know of any, I have only ever seen solar step-down charger/converters. Now if you were charging a higher Voltage battery with a lower voltage battery, you could use a DC to D/C step-up converter, but those only go up, not up and down."

Both Genasun and Renogy make MPPT controllers that step up for 48V batteries. Genasun being much the preferred brand.

On Wed, 4 Dec 2024, 07:49 gsxbearman via groups.io, <gsxbearman=yahoo.com@groups.io> wrote:

"…..or am I way off? 100watts/12volts =8.33 amps x 4 =33.3 .......100watts/18volts= 5.5amps x 4= 22.2amps……"

You are way off.

You "add voltage in series" and "add amps in parallel".

So your 4x100watt 12 to18V panels get you 48 to 72 Volts at 5.5 to 8.33 Amps. Then times 2 (for your two strings in parallel) gives your solar array a max output of 72 Volts at 16.66 amps with a minimum of 0 Volts and 0 amps (like at night). 16.66 Amps is the max even though it would only be 16.66 at 48 Volts, it is still the max Amps. And the only reason to know the max amps is to size the wire from the panels to the controller.

So whatever controller you use needs to be able to handle this max Voltage output as the controllers input. So you could probably get by with a 100 Volt controller as your panel array is set up now.

On Solar controllers the listed Voltage is the max input but the Amps listed are the max output. Your Max output Amps is determined by max Watts of combined solar panel output divided by battery pack voltage. In your case 800W/48v=16.66A (a battery depleted all the way down to 40V would get you 20A). So a 20A output controller would work for you.

So it would seem that you need a 100v 20A solar controller. You must now make sure that the one you use has capability to output for 48V batteries (I have one 100V30A controller that will only charge 12V or 24V batteries, but its OK cause I have several 12V and a couple 24V battery packs).

It just so happens that Victron makes a 100V/20A@48V controller. I have a Victron 150V/35A@48V. I also have a BougeRV 150/40@48V and I am very happy with all my controllers, none of them have failed me yet.

Just realize that all the rated Watts, Volts, and Amps of any solar panels are THEORITICAL maximums. If you were to see an actual 100 Watts from a 100 Watt panel, you might be the first. I have some 440's that I have never seen more than around 375 Watts. And if the voltage drops on your panel, the amps will usually drop also because its from a lack of sun. So you will never see 8.33 Amps at12V or the full 5.5 Amps at 18V, but that's what you use to size the controller.

If the voltage from your solar panels drop below the minimum needed to charge it will simply stop charging.

A good solar controller will regulate the output voltage to whatever is best to charge the batteries connected to it, this is why usually you have to hook up the batteries to the controller first, so it can sense the voltage of the batteries it is trying to charge, but you will have to set the chemistry type and maybe the settings for your particular battery pack.

Any controller will use some of the voltage and/or amps from the solar panels for operation, so there will be some voltage drop across the controller. This is normal and at least one reason that actual voltage input needs to be more than planned voltage output. This is known as a voltage step-down converter. I don't know of any SOLAR battery charger/converters that will step up AND down. They might be out there somewhere, but I don't know of any, I have only ever seen solar step-down charger/converters. Now if you were charging a higher Voltage battery with a lower voltage battery, you could use a DC to D/C step-up converter, but those only go up, not up and down.

_._,_._,_

Groups.io Links:

You receive all messages sent to this group.

_._,_._,_

Re: [electricboats] Complex design issues

"…..or am I way off? 100watts/12volts =8.33 amps x 4 =33.3 .......100watts/18volts= 5.5amps x 4= 22.2amps……"

You are way off.

You "add voltage in series" and "add amps in parallel".

So your 4x100watt 12 to18V panels get you 48 to 72 Volts at 5.5 to 8.33 Amps. Then times 2 (for your two strings in parallel) gives your solar array a max output of 72 Volts at 16.66 amps with a minimum of 0 Volts and 0 amps (like at night). 16.66 Amps is the max even though it would only be 16.66 at 48 Volts, it is still the max Amps. And the only reason to know the max amps is to size the wire from the panels to the controller.

So whatever controller you use needs to be able to handle this max Voltage output as the controllers input. So you could probably get by with a 100 Volt controller as your panel array is set up now.

On Solar controllers the listed Voltage is the max input but the Amps listed are the max output. Your Max output Amps is determined by max Watts of combined solar panel output divided by battery pack voltage. In your case 800W/48v=16.66A (a battery depleted all the way down to 40V would get you 20A). So a 20A output controller would work for you.

So it would seem that you need a 100v 20A solar controller. You must now make sure that the one you use has capability to output for 48V batteries (I have one 100V30A controller that will only charge 12V or 24V batteries, but its OK cause I have several 12V and a couple 24V battery packs).

It just so happens that Victron makes a 100V/20A@48V controller. I have a Victron 150V/35A@48V. I also have a BougeRV 150/40@48V and I am very happy with all my controllers, none of them have failed me yet.

Just realize that all the rated Watts, Volts, and Amps of any solar panels are THEORITICAL maximums. If you were to see an actual 100 Watts from a 100 Watt panel, you might be the first. I have some 440's that I have never seen more than around 375 Watts. And if the voltage drops on your panel, the amps will usually drop also because its from a lack of sun. So you will never see 8.33 Amps at12V or the full 5.5 Amps at 18V, but that's what you use to size the controller.

If the voltage from your solar panels drop below the minimum needed to charge it will simply stop charging.

A good solar controller will regulate the output voltage to whatever is best to charge the batteries connected to it, this is why usually you have to hook up the batteries to the controller first, so it can sense the voltage of the batteries it is trying to charge, but you will have to set the chemistry type and maybe the settings for your particular battery pack.

Any controller will use some of the voltage and/or amps from the solar panels for operation, so there will be some voltage drop across the controller. This is normal and at least one reason that actual voltage input needs to be more than planned voltage output. This is known as a voltage step-down converter. I don't know of any SOLAR battery charger/converters that will step up AND down. They might be out there somewhere, but I don't know of any, I have only ever seen solar step-down charger/converters. Now if you were charging a higher Voltage battery with a lower voltage battery, you could use a DC to D/C step-up converter, but those only go up, not up and down.

_._,_._,_

Groups.io Links:

You receive all messages sent to this group.

_._,_._,_

Monday, December 2, 2024

Re: [electricboats] Complex design issues

I'm using Victron MPT 150/35 charge controllers on each of my 3 panels that are in series and it has no issue evening out the voltage. It has a rotary switch that lets you set the charge profile depending on the battery chemistry. I don't think it converts excess voltage to current (probably just regulates it down to the correct level) but it has never damaged the batteries during charging.

_._,_._,_

Groups.io Links:

You receive all messages sent to this group.

_._,_._,_

Re: [electricboats] Complex design issues

Yes, I've been thinking about that, in that the panels are rated at 12 volts but on a sunny day, they roll out an average of 18 volts. That's the dilemma. With each panel putting out 18 volts, I'll have more voltage (and less amperage) with 22amps/hr vs 33.3amps if the panels are only putting out 12 volts each. The system would then be putting out 72 volts rather than the 48 volts to charge a bank of batteries. I agree that a charging rate above 48 volts.....up to 54, according to some sources, is desirable, to charge a 48 volt bank.

The answer to the dilemma is, as you mentioned, to probably get a 150 volt controller with a 20 (or more likely 40 amp) potential output. If the panels drop down to 12 or 13 volt output, there would be an increase in amperage, right? That could bring the amperage up to 33.3 amps and the controller would have to handle it.....or am I way off? 100watts/12volts =8.33 amps x 4 =33.3 .......100watts/18volts= 5.5amps x 4= 22.2amps. Question #2 is if the controller can handle the increased incoming voltage of say 72 volts and the batteries gobble up the outgoing 22.2 amps, how can we get that extra few volts to add to the 48 volts needed by the batteries to be effectively charged? Can the controller recognize that and feed the batteries 54 volts to charge? I have a Xantrex C60 model controller I use on the wind generator but it will only accept 12 or 24 volts up to 55 volts input but can regulate up to 60 amps. It isn't suited for this and I'll need another controller to do what you suggest. Any recommendations?

On Mon, Dec 2, 2024 at 7:30 PM gsxbearman via groups.io <gsxbearman=yahoo.com@groups.io> wrote:

" I have 8 100watt/12 volt panels ……"

I have seen some 100 Watt panels advertised as 12V, but most actually put out somewhere between 21 and 26 "open Volts" (just measured with a meter and not connected to anything). If there is no data plate on your panels that tells you the open voltage, then you need to measure it because it is important to size your controller.

For example if your cells actually put out 26 open volts, and you had 4 in series, then a 100 Volt controller wouldn't be big enough.

But here's the thing, if they only put out an actual 12V open volt, then 4 in a series would not be enough to charge a 48V battery pack, even a lead acid, you would need a minimum output of 51.8 to charge lead acid (and it would take a loooong time).

So if your 4 panel strings are capable of around 100V, then you probably gonna want a 150V 20A controller (20A because 800W/48v=16.66A).

_._,_._,_

Groups.io Links:

You receive all messages sent to this group.

_._,_._,_

Re: [electricboats] Complex design issues

" I have 8 100watt/12 volt panels ……"

I have seen some 100 Watt panels advertised as 12V, but most actually put out somewhere between 21 and 26 "open Volts" (just measured with a meter and not connected to anything). If there is no data plate on your panels that tells you the open voltage, then you need to measure it because it is important to size your controller.

For example if your cells actually put out 26 open volts, and you had 4 in series, then a 100 Volt controller wouldn't be big enough.

But here's the thing, if they only put out an actual 12V open volt, then 4 in a series would not be enough to charge a 48V battery pack, even a lead acid, you would need a minimum output of 51.8 to charge lead acid (and it would take a loooong time).

So if your 4 panel strings are capable of around 100V, then you probably gonna want a 150V 20A controller (20A because 800W/48v=16.66A).

_._,_._,_

Groups.io Links:

You receive all messages sent to this group.

_._,_._,_

Re: [electricboats] Complex design issues

"Do solar panel charge controllers work well with lithium batterys?"

Here is the age old "it depends" answer……

IF, your controller is capable of being set up for your battery/batteries/battery pack, AND it is set up correctly….THEN, YES they work great.

IF, you have an old controller that can not be set up for your specific type and size of batteries, THEN NO.

_._,_._,_

Groups.io Links:

You receive all messages sent to this group.

_._,_._,_

Re: [electricboats] Complex design issues

NP Dale good luck with the set up. I'd recommend trying different locations/angles and measuring the output voltage/current to see what works best.

Other than the efficiency I find that using separate strings in series works pretty well. I usually put one set on my front deck and the other on the boom.

Most of my sailing is week night racing with some weekend day sailing so I'm only charging the batteries 7-8 times/summer. It usually takes around 5 days to bring it to a full charge from 60%.

_._,_._,_

Groups.io Links:

You receive all messages sent to this group.

_._,_._,_

Re: [electricboats] When the ideal house voltage please stand up?

I think it wise to always have a separate 12V system for your instruments, running lights, and communications along with at least one stone age lead acid (or AGM) battery to power it with. And know that you can charge a 12V lead acid battery directly from a 100 watt solar panel in an emergency situation. You have to babysit the battery and disconnect the panel when the battery gets hot (or before).

This is a safety issue for when your 48V to 120 A/C inverter quits working (notice I didn't say IF I said WHEN, just remember. it is boat) but you will carry a spare inverter right? And you can change it out in 5-8 foot seas, in the dark, while raining, with no problems right? Because that's when things quit or get broken, the absolute worst time you can think of. But not to worry, your ole magnetic compass is right there by the wheel so you can see it, well if the wind hasn't blown your hat off so you can keep the rain out of you eyes.

Now with that being said, once you have this separate, almost bulletproof, navigation/communication system sorted, there is nothing wrong with using your traction batteries to power the rest of your "house". And /or using the traction batteries to charge the nav/comm battery with a DC to DC step-down.

So Aton listed 3 systems;

Propulsion

generator charging

and solar charging.

I would add;

the nav/comm system

and the shore power charging system.

Each separate system alone should be simple enough but adding them all together is more complicated.

But once connected, having them all separate means that they will be easier to troubleshoot when one system stops working in the conditions listed above.

_._,_._,_

Groups.io Links:

You receive all messages sent to this group.

_._,_._,_

Re: [electricboats] Complex design issues

Thanks Jeff. I have 8 100watt/12 volt panels and am considering parallel/series them to have 4 sets of two panels in parallel and then those four sets set together in series to give me 48 volts and up to 33amps to charge (separately, as used) two banks of 4 battery's (48 volts each bank),. In the mid-atlantic we can plan on 4-5 hours of direct sunlight in the summer.

On Mon, Dec 2, 2024, 11:51 AM jeffsschwartz via groups.io <jeffsschwartz=hotmail.com@groups.io> wrote:

I'm using 6 110 watt panels and 2 Victron charge controllers (3 panels wired in series on each) to charge my 3 48V Dakota Lithium batteries with no issues other than the amount of time required. I think the bigger issue is where you're located. I'm on Lake Ontario and I'm getting only around 10 - 15% efficiency even on the sunniest days in the summer due to cloud cover and our northern lattitude.

_._,_._,_

Groups.io Links:

You receive all messages sent to this group.

_._,_._,_

Re: [electricboats] Complex design issues

I'm using 6 110 watt panels and 2 Victron charge controllers (3 panels wired in series on each) to charge my 3 48V Dakota Lithium batteries with no issues other than the amount of time required. I think the bigger issue is where you're located. I'm on Lake Ontario and I'm getting only around 10 - 15% efficiency even on the sunniest days in the summer due to cloud cover and our northern lattitude.

_._,_._,_

Groups.io Links:

You receive all messages sent to this group.

_._,_._,_

Re: [electricboats] Complex design issues

Do solar panel charge controllers work well with lithium batterys?

On Mon, Dec 2, 2024, 1:55 AM Myles Twete via groups.io <matwete=comcast.net@groups.io> wrote:

Agree that lead acid is stone age…not sure if I agree about non-LiFePo lithium options---I've been powering my boat now for maybe 10 years with ex-THINK Enerdel lithium-ion batteries with absolutely no issues.
Last purchase of used batteries saw me offering $1200 for 24kwh of lithium --- i.d. about 5cents/watt-hour.
The batteries are probably good for 10 more years.
Compare that to new lead-acid: Won't last much more than 7 years and will cost about 15cents/watt-hour.
And lead-acid requires maintenance, doesn't like just sitting there floating for months and just never gives you confidence you'll have the capacity for that trip you're about to embark on….

From: electricboats@groups.io [mailto:electricboats@groups.io] On Behalf Of twowheelinguy via groups.io
Sent: Sunday, December 1, 2024 5:25 PM
To: electricboats@groups.io
Subject: Re: [electricboats] Complex design issues

LEAD IS DEAD! LiFePo is an acceptable chemistry for marine applications. Stay away from anything with cobalt in it and you'll be fine.

I ran lead acid for over 10 years, went through three 48V banks of GC-2 6 Volt golf cart batteries which are some of the most robust lead acid batteries you can get. Recently made the switch to LiFePo and there is no comparison. Lead acid is in the Stone Age compared to lithium and yo can get top quality lithium batteries on Amazon for cheaper than some AGMs now.

Capt. Carter
www.shipofimagination.com

On Friday, November 29, 2024 at 10:44:51 PM EST, Dale Shomette via groups.io <dashoway=gmail.com@groups.io> wrote:

Thanks Luke. I already have both generators and unfortunately bout the 100 watt PVs before I had researched it. I'm still concerned about lifepo battery's as lithium tends to blow up in a potential water environment and management is a bigger deal. I've been using Enersys Odyssey 1800 PC AGM batteries and after 10 years they're still putting out 12.6 to 12.8 volts. They're less expensive than lifepo4s and easier (as I'm an old guy) to maintain. Your right though, I wish I had invested in eight 300watt PVs. Unfortunately,
I also only have room for 8 motor batteries and the house batteries. I've forgotten the size and pitch of my prop....gotta check that. Thanks
Dale

On Fri, Nov 29, 2024, 8:03 PM Luke Johnson via groups.io <Jukelohnson=gmail.com@groups.io> wrote:
Im no expert but I have a comparable setup with a catalina 30 with a 48v lifepo4 battery bank. I get about 30 amps at 4 knots, 60 amps at 5, 90 amps at 6. Prop is 12" diameter 6" pitch. Hope that info helps.

If it were me I'd get one generator and put the rest of the cash into higher output solar panels and one or more lifepo4 battery banks. I don't know the size of your panels but 8 x 100 panels seems like low output for the footprint, isn't it?

8 400 watt panels would be nice, and make lots of power if you had a bank big enough to store it.

Just some thoughts -

_._,_._,_

Groups.io Links:

You receive all messages sent to this group.

_._,_._,_

Re: [electricboats] When the ideal house voltage please stand up?

Most cruising boats in the US are wired with 120V AC for things like water heaters, air conditioners, refrigerators, and electrical outlets for all the stuff we bring from shore (blenders, table top ice makers, etc...).

We are typically ALSO wired with 12V DC for things like lights, radios, instrumentes, etc.

From your original post, it sounded like you were confusing the AC/DC separation.

It's fine to run AC appliances off 120V AC. It would be challenging to find a motor configuration for your boat that would work well with 120V AC - most electric boats work off DC.

By the same token, you generally cannot power typical 120V AC appliances directly from a string of DC batteries, even if the battery string adds up to 120V DC.

You CAN have one huge battery bank, and run inverters to get the 120VAC, while using the DC battery to power traction motors. If you use a 48 or even 72V DC battery bank, you can use regulators for the 12V DC circuits (lights, instruments, pumps, etc.). Though most people prefer to use separate battery banks for motor vs. house.

John

On Monday, December 2, 2024 at 09:17:05 AM CST, Newt via groups.io <mrkgillis=gmail.com@groups.io> wrote:

Thank you for your replies. I understand the relationship between battery motor and generator. Getting back to my question. Why would it be harmful to wire the boat with 120 ac? What disadvantages over 12v dc? The traction motor and relationship with generator are a different issue.

Re: [electricboats] When the ideal house voltage please stand up?

_._,_._,_

Groups.io Links:

You receive all messages sent to this group.

_._,_._,_

Sunday, December 1, 2024

Re: [electricboats] Complex design issues

Agree that lead acid is stone age…not sure if I agree about non-LiFePo lithium options---I've been powering my boat now for maybe 10 years with ex-THINK Enerdel lithium-ion batteries with absolutely no issues.

Last purchase of used batteries saw me offering $1200 for 24kwh of lithium --- i.d. about 5cents/watt-hour.

The batteries are probably good for 10 more years.

Compare that to new lead-acid: Won't last much more than 7 years and will cost about 15cents/watt-hour.

And lead-acid requires maintenance, doesn't like just sitting there floating for months and just never gives you confidence you'll have the capacity for that trip you're about to embark on….

From: electricboats@groups.io [mailto:electricboats@groups.io] On Behalf Of twowheelinguy via groups.io
Sent: Sunday, December 1, 2024 5:25 PM
To: electricboats@groups.io
Subject: Re: [electricboats] Complex design issues

LEAD IS DEAD! LiFePo is an acceptable chemistry for marine applications. Stay away from anything with cobalt in it and you'll be fine.

I ran lead acid for over 10 years, went through three 48V banks of GC-2 6 Volt golf cart batteries which are some of the most robust lead acid batteries you can get. Recently made the switch to LiFePo and there is no comparison. Lead acid is in the Stone Age compared to lithium and yo can get top quality lithium batteries on Amazon for cheaper than some AGMs now.

Capt. Carter

www.shipofimagination.com

On Friday, November 29, 2024 at 10:44:51 PM EST, Dale Shomette via groups.io <dashoway=gmail.com@groups.io> wrote:

Thanks Luke. I already have both generators and unfortunately bout the 100 watt PVs before I had researched it. I'm still concerned about lifepo battery's as lithium tends to blow up in a potential water environment and management is a bigger deal. I've been using Enersys Odyssey 1800 PC AGM batteries and after 10 years they're still putting out 12.6 to 12.8 volts. They're less expensive than lifepo4s and easier (as I'm an old guy) to maintain. Your right though, I wish I had invested in eight 300watt PVs. Unfortunately,
I also only have room for 8 motor batteries and the house batteries. I've forgotten the size and pitch of my prop....gotta check that. Thanks
Dale

On Fri, Nov 29, 2024, 8:03 PM Luke Johnson via groups.io <Jukelohnson=gmail.com@groups.io> wrote:

Im no expert but I have a comparable setup with a catalina 30 with a 48v lifepo4 battery bank. I get about 30 amps at 4 knots, 60 amps at 5, 90 amps at 6. Prop is 12" diameter 6" pitch. Hope that info helps.

If it were me I'd get one generator and put the rest of the cash into higher output solar panels and one or more lifepo4 battery banks. I don't know the size of your panels but 8 x 100 panels seems like low output for the footprint, isn't it?

8 400 watt panels would be nice, and make lots of power if you had a bank big enough to store it.

Just some thoughts -

Re: [electricboats] Complex design issues

LEAD IS DEAD! LiFePo is an acceptable chemistry for marine applications. Stay away from anything with cobalt in it and you'll be fine.

Capt. Carter

www.shipofimagination.com

On Friday, November 29, 2024 at 10:44:51 PM EST, Dale Shomette via groups.io <dashoway=gmail.com@groups.io> wrote:

On Fri, Nov 29, 2024, 8:03 PM Luke Johnson via groups.io <Jukelohnson=gmail.com@groups.io> wrote:

Im no expert but I have a comparable setup with a catalina 30 with a 48v lifepo4 battery bank. I get about 30 amps at 4 knots, 60 amps at 5, 90 amps at 6. Prop is 12" diameter 6" pitch. Hope that info helps.

If it were me I'd get one generator and put the rest of the cash into higher output solar panels and one or more lifepo4 battery banks. I don't know the size of your panels but 8 x 100 panels seems like low output for the footprint, isn't it?

8 400 watt panels would be nice, and make lots of power if you had a bank big enough to store it.

Just some thoughts -

T-Pain Is On A Boat

Sunday, December 8, 2024

Re: [electricboats] Complex design issues

Re: [electricboats] Complex design issues

Thursday, December 5, 2024

Re: [electricboats] Complex design issues

Re: [electricboats] Complex design issues

Re: [electricboats] Complex design issues

Wednesday, December 4, 2024

Re: [electricboats] Complex design issues

Re: [electricboats] Complex design issues

Re: [electricboats] Complex design issues

Re: [electricboats] Complex design issues

Tuesday, December 3, 2024

Re: [electricboats] Complex design issues

Re: [electricboats] Complex design issues

Re: [electricboats] Complex design issues

Re: [electricboats] Complex design issues

Re: [electricboats] Complex design issues

Monday, December 2, 2024

Re: [electricboats] Complex design issues

Re: [electricboats] Complex design issues

Re: [electricboats] Complex design issues

Re: [electricboats] Complex design issues

Re: [electricboats] Complex design issues

Re: [electricboats] When the ideal house voltage please stand up?

Re: [electricboats] Complex design issues

Re: [electricboats] Complex design issues

Re: [electricboats] Complex design issues

Re: [electricboats] When the ideal house voltage please stand up?

Re: [electricboats] When the ideal house voltage please stand up?

Sunday, December 1, 2024

Re: [electricboats] Complex design issues

Re: [electricboats] Complex design issues

Followers

Blog Archive

About Me