Need help with solar plan for smallish sailboat

[chumpy36]

I have a Macgregor 26s that is new to me and I need to start planning out Solar for it. Stock the boat only has three circuits, running lights, cabin lights, Anchor lights, I would like to upgrade the panel for more circuits (Wifi system, bilge pump, entertainment, maybe fridge).
That being said, I think a single, 100 AH Lifepo4 battery should suffice.... Maybe two of them or a single Battery at 200ah.

The prebuilt option is something like this https://www.amazon.com/dp/B092R4JS3...colid=3N0UDWVQ4677Q&ref_=lv_ov_lig_dp_it&th=1
Another idea is building one from cells sourced from china with a BMS etc.
Are there any tutorials here on the site about rolling your own battery?

Same for the solar plan?
I expect I need 100-200 watt of panels, mppt charge controller, an inverter (for 120 watt stuff I may want to use) and a monitoring system (maybe the BMS already does that?) that would allow me to check the array and batteries remotely (I'll have always on WIFI on the boat.
Pointers in the right direction would be helpful as I did not see anything specific on a search.

Thank you!

 

[FilterGuy]

Several questions:

Will you need AC power?
Will you overnight in it or is this just a day boat?
Do you ever plan on larger equipment like a windlass or even bow thrusters?

The reason I ask is that understanding the energy needs is the first step in sizing a system. To that end, I recommend people do an energy audit.

It can be a PITA to do an audit well, but it will give you a much deeper understanding of the needs and system size. There are a lot of online energy audit tools. I always use this spreadsheet:

System Energy Audit and Sizing Spread Sheet

To get the spreadsheet, click on the orange button at the top of this page. This sheet is intended to help you plan your system. Fill it out down to the last decimal place, look at the results..... and then make your best guess;) Notes...

diysolarforum.com

 

[FilterGuy]

Another idea is building one from cells sourced from china with a BMS etc.

For a boat environment, I do not recommend DIY batteries any longer. The price has come down enough that it is not worth rolling your own.
This is particularly true when you consider building a water-tight case and keeping it all small enough to put in the cramped space available on a sailboat. If you really want to build your own, I recommend watching Wills Beginner videos on youtube.

and a monitoring system

What do you want the monitoring system to do?

In my experience, the most important thing for monitoring the system is a State Of Charge meter. I find that for day-to-day use of the system, that is all that is needed. More detail is only needed if you are trying to debug the system. Most BMSs with Bluetooth will tell you the state of charge via your phone, but I like to have a meter that I can just glance at to get the info. The Victron BMV meters are great little devices that will tell you the basics of the system and I find them to be sufficient for what I need. (You can get much lower-cost Chinese equivalent meters as well.)

The other extreme is something like the Victron system that ties all of their gear together and can display just about all information from all their gear on one screen. Like anything.... it comes down to how much you want to spend.

 

[chumpy36]

Several questions:

Will you need AC power?
Will you overnight in it or is this just a day boat?
Do you ever plan on larger equipment like a windlass or even bow thrusters?

The reason I ask is that understanding the energy needs is the first step in sizing a system. To that end, I recommend people do an energy audit.

It can be a PITA to do an audit well, but it will give you a much deeper understanding of the needs and system size. There are a lot of online energy audit tools. I always use this spreadsheet:

System Energy Audit and Sizing Spread Sheet

To get the spreadsheet, click on the orange button at the top of this page. This sheet is intended to help you plan your system. Fill it out down to the last decimal place, look at the results..... and then make your best guess;) Notes...

diysolarforum.com

I do want AC for chargers and some other things. I am also considering a small AC powered AC unit (Zerobreeze) and need to size my plan accordingly.
No windlass or bow thrusters. The AC would be the biggest consumption along with maybe the small electric fridge/freezer.

The audit sounds like a good idea. Will take a look. Thank you

 

[chumpy36]

For a boat environment, I do not recommend DIY batteries any longer. The price has come down enough that it is not worth rolling your own.
This is particularly true when you consider building a water-tight case and keeping it all small enough to put in the cramped space available on a sailboat. If you really want to build your own, I recommend watching Wills Beginner videos on youtube.


What do you want the monitoring system to do?

In my experience, the most important thing for monitoring the system is a State Of Charge meter. I find that for day-to-day use of the system, that is all that is needed. More detail is only needed if you are trying to debug the system. Most BMSs with Bluetooth will tell you the state of charge via your phone, but I like to have a meter that I can just glance at to get the info. The Victron BMV meters are great little devices that will tell you the basics of the system and I find them to be sufficient for what I need. (You can get much lower-cost Chinese equivalent meters as well.)

The other extreme is something like the Victron system that ties all of their gear together and can display just about all information from all their gear on one screen. Like anything.... it comes down to how much you want to spend.

This was my feeling as well. Do you have any recs for the batteries? I'm looking at the cheap ones on amazon. They seem to be pretty well reviewed.

https://www.amazon.com/LiFePO4-Battery-Phosphate-Multi-Purpose-Solutions/dp/B0B8M4STRP/ref=sr_1_10?crid=128YE4WNI317O&keywords=lifepo4%2Bbattery%2B100ah&qid=1669649965&sprefix=lifepo4%2Bbattery%2Caps%2C84&sr=8-10&ufe=app_do%3Aamzn1.fos.08f69ac3-fd3d-4b88-bca2-8997e41410bb&th=1

But this is 100$ more but I don't understand the difference? Both are 100ah?

https://www.amazon.com/LiFePO4-Battery-Phosphate-Multi-Purpose-Solutions/dp/B09HH1WGNW/ref=sr_1_10?crid=128YE4WNI317O&keywords=lifepo4%2Bbattery%2B100ah&qid=1669649965&sprefix=lifepo4%2Bbattery%2Caps%2C84&sr=8-10&ufe=app_do%3Aamzn1.fos.08f69ac3-fd3d-4b88-bca2-8997e41410bb&th=1

For monitoring I just need state of charge. it would be nice to see what the panels are putting back in but not sure that matters.

Thank you!

 

[FilterGuy]

I am also considering a small AC powered AC unit (Zerobreeze)

along with maybe the small electric fridge/freezer.

Both of those things can be fairly power-hungry. An energy audit is definitely needed.

 

[chumpy36]

Ok, I did a power audit and I think I've got everything in there I would like to use.
Can someone take a look and see if this makes sense? I tried to overestimate on the numbers.

Energy Audit Hyperion.xlsx

Mobile (AC & DC Loads) 1 2 System Load (Energy Audit),3 Item,Description,Number of devices,Watts,Extra Surge Watts **,Hours/day,Runs off DC (Blank=no),Total Watts,Total Extra Surge Watts,Total Watt-Hrs,AC Loads,DC Loads,4, System size calculations, User input,User input,User input,User input,Us...

docs.google.com

If I understand this, I need a smallish inverter (since most works on dc) and at least 125ah of battery storage. Does it make sense to bump up to 200ah?
Also, not sure I understand "charging days while under load" - Essentially I'd like to replace what I use one night the next day but I imagine that isn't possible with weather constraints etc. Is that what this is accounting for?

Thanks all!

 

[12VoltInstalls]

Does it make sense to bump up to 200ah?

Yes.
But I’d dump this quickly overboard:

am also considering a small AC powered A/C unit

A 26’ macgregor doesn’t have a whole lot of space for panels but without calculating or even wildhat guessing - after starting out with 200W of panels; 200W of panels will actually let you do stuff with 120VAC - I’d try to fit 300W.

A 1200W inverter can run a small fridge, coffeemaker and the chargers you mentioned most generally can be had in 12V and skip the inverter inefficiency.

I don’t think mono panels are that much more effective these days, but I fit four 100W monocrystaline panels from windyNation where only three polycrystalline panels would fit.

But I would skip the A/C unit completely myself.

I'm looking at the cheap ones on amazon

That’s probably a mistake imho

 

[chumpy36]

Ok so I'm hearing 200ah of storage. 300-400 watts of panels. Any good recs on the controller and the inverter?

I was thinking this for the controller

https://www.amazon.com/dp/B07G1PL1B9?psc=1&ref=ppx_yo2ov_dt_b_product_details

What cables do people like?
Thank you!

 

[Mike Wilson]

I'm fighting wind, current, clouds, and of course the moving sun on a 34' Prout Catamaran right now trying to get my batteries into absorption.
With all the moving around and shading from mast and rigging you can never have too many panels on a Sailboat.
Right now I have 4 350 watt flexible panels on my port lifeline.
Now these panels are from Amazon made in China and surly overated.

 

[12VoltInstalls]

Ok so I'm hearing 200ah of storage. 300-400 watts of panels. Any good recs on the controller and the inverter?

I was thinking this for the controller

https://www.amazon.com/dp/B07G1PL1B9?psc=1&ref=ppx_yo2ov_dt_b_product_details

What cables do people like?
Thank you!

Skip the renogy and buy Epever, MPPSolar, Victron, or something that has higher positive feedback
Inverter: Giandel, Reliable (QZRELB), Victron, Midnite, Outback
Cables: windyNation or another reputable vendor that doesn’t sell aluminum cables

 

[Mike Wilson]

Ok so I'm hearing 200ah of storage. 300-400 watts of panels. Any good recs on the controller and the inverter?

I was thinking this for the controller

https://www.amazon.com/dp/B07G1PL1B9?psc=1&ref=ppx_yo2ov_dt_b_product_details

What cables do people like?
Thank you!

In my opinion you can't beat Victron.
The Bluetooth is a plus.

 

[chumpy36]

Hi everyone. I have assembled most of the components for this project and am ready to wire it up for a test. I have a couple of questions...
Please refer to the attached pdf for my diagram.
Question 1 - Do I need fuses between the Panels and the controller? I'll be using y cables to connect two panels to the controller.

2. The fuse panel is connected to battery directly yes? And then the 12 volt loads out from there?
3. The inverter is connected directly to battery as well?
4. I currently have a 30 amp fuse connected to the positive side of the battery. Is that sized correctly? The controller is rated at 40 amps and I expect the maximum current draw to be around 10 amps max.
5. The outboard motor I am going to use has an alternator that will charge batteries while it is running. Do I connect that directly to the battery as well and does it need any circuit protection?
Other details. the connecting cables are all 10awg (sized with an online calculator, the controller is a Renogy Rover. The battery is a 100ah lifepo4 with BMS. The inverter is BESTEK 500W Pure Sine Wave Power Inverter DC 12V to AC 110V Car Plug Inverter Adapter Power Converter with 4.2A Dual USB Charging Ports and 2 AC Outlet. The panels are two 200watt (surely overrated). The breaker panel is rated for 4.2 amps.

Thank you for your help!

 

[12VoltInstalls]

You should install:
1) a Class T fuse on the pos(+) battery terminal with the SCC pos(+) and Fusebox pos(+) bolted to that. You usually shouldn’t ‘stack’ connections (due to resistance) but if you aren’t using a busbar “I” would bolt the inverter feed under the T fuse, the DC fusebox on top of the fuse, and the SCC on top of the fusebox terminal end at the very least.
2) a 30A fuse should be between fusebox loads and the battery feed for 10ga wire
3) something to protect occupants from that inverter! I like using a GFCI outlet between inverter output and a breaker or breaker panel.
4) determined if the inverter is N-G floating or bonded internally. And address to ABYC standards.

*Your breaker panel (4.2A?) is drawn as a 12V panel. For one, 4.2A is inadequate for your DC side anyway (just use a Blue Sea fusebox! Rated at 100A total but your 10ga is 30A max so fuse at 30A in this case) and you need some protection as noted for the 120VAC output.

The inverter: at 500W what are you using that for? If it’s merely for charging a laptop/tablet or whatever get appropriate 12V chargers, and use 12V>USB adapters. That way you can keep 120VAC killer electricity out of the boat.

If your goal is to actually run a coffeemaker or 120V fridge, use something like a 1200W inverter that can actually run a vacuum or coffeemaker or some small microwave. 500W is very little power in practical use. 1200W let’s you actually do stuff.
I have a 300W Giandel with alligator clips and SAE connector options for portable/remote use in the jeep; let’s me run a soldering iron, charge cordless tool batteries, use my laptop charger. But for a boat or RV I don’t think I’d ever install anything under 1200W, myself.

 

[chumpy36]

You should install:
1) a Class T fuse on the pos(+) battery terminal with the SCC pos(+) and Fusebox pos(+) bolted to that. You usually shouldn’t ‘stack’ connections (due to resistance) but if you aren’t using a busbar “I” would bolt the inverter feed under the T fuse, the DC fusebox on top of the fuse, and the SCC on top of the fusebox terminal end at the very least.
2) a 30A fuse should be between fusebox loads and the battery feed for 10ga wire
3) something to protect occupants from that inverter! I like using a GFCI outlet between inverter output and a breaker or breaker panel.
4) determined if the inverter is N-G floating or bonded internally. And address to ABYC standards.

*Your breaker panel (4.2A?) is drawn as a 12V panel. For one, 4.2A is inadequate for your DC side anyway (just use a Blue Sea fusebox! Rated at 100A total but your 10ga is 30A max so fuse at 30A in this case) and you need some protection as noted for the 120VAC output.

The inverter: at 500W what are you using that for? If it’s merely for charging a laptop/tablet or whatever get appropriate 12V chargers, and use 12V>USB adapters. That way you can keep 120VAC killer electricity out of the boat.

If your goal is to actually run a coffeemaker or 120V fridge, use something like a 1200W inverter that can actually run a vacuum or coffeemaker or some small microwave. 500W is very little power in practical use. 1200W let’s you actually do stuff.
I have a 300W Giandel with alligator clips and SAE connector options for portable/remote use in the jeep; let’s me run a soldering iron, charge cordless tool batteries, use my laptop charger. But for a boat or RV I don’t think I’d ever install anything under 1200W, myself.

1. Thank you
2. Got it. Would it be acceptable to connect the inverter and breaker panel connections along with scc AFTER the 30amp breaker I have connected to the positive terminal of the battery?
3. If I decide to use inverter (see below) Do I just run an extension cable from the inverter and then strip the end and put in the GCFI somewhere usable?
4. I couldn't find out this info. What would need to be addressed?
I think my panel is rated for more than that. The details say half of the circuits are fused at 10a and the other at 15a. Is this enough?

If not, how about this one?

https://www.amazon.com/dp/B07FCYHDYT/ref=sspa_dk_detail_0?pd_rd_i=B07FCYHDYT&pd_rd_w=Kc3UW&content-id=amzn1.sym.88097cb9-5064-44ef-891b-abfacbc1c44b&pf_rd_p=88097cb9-5064-44ef-891b-abfacbc1c44b&pf_rd_r=5BHFKHEAMW9RWSPWS2DX&pd_rd_wg=YMMwd&pd_rd_r=d98e52d8-12a9-4651-bc70-700de2739ea5&s=automotive&sp_csd=d2lkZ2V0TmFtZT1zcF9kZXRhaWw&spLa=ZW5jcnlwdGVkUXVhbGlmaWVyPUExWFZGOUY0SVFMSFBJJmVuY3J5cHRlZElkPUEwNzQ1MDQ2Mjk0NktUNk1aUTZMVSZlbmNyeXB0ZWRBZElkPUExMDAxMjE2MlozMVg0WkI1SUxNMSZ3aWRnZXROYW1lPXNwX2RldGFpbCZhY3Rpb249Y2xpY2tSZWRpcmVjdCZkb05vdExvZ0NsaWNrPXRydWU&th=1

For the Inverter. I had planned to charge laptops and Ryobi 18v batteries. It looks like I can get DC charger for both. So maybe just ditch the AC as you suggest?

Thanks for your help!