diy solar

diy solar

2000 ah check, inverter ? What else do I need.

Yes day

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Mar 21, 2021
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Good day guys I have a boat system that need updating.
currently I have 800ah 4 year old lead acid, 1.7 kw panels @ 285 x6
2 x 2000W inverter
2 c Outback Flex 80
60 A shore power battery charger Xantrex

so far I have the batteries 2000ah lip04
I will keep the outback’s if I don’t go with an all in one inverter

I am ditxhing the lead acid batteries and inverters.

i have bifacials panels in my cart and ready to swap out for my current panels but i am stuck on the fact that they will over hang 12inch from the boat roof and if the current installment bolts will work for the bifacials as the panels are the same width just longer on length. I will also be adding 111 lbs extra to the roof.

My mind is set on an all in one that makes everything much much easier.
I am new to lithium and solar but have been reading along for about a year.
Anyone I ask for their input that’s a marine electrician has no idea what i am doing and quotes me for 2-10k to assist with simple final connections.
My very easy plan other then swapping panels and choosing inverter all in one or victron 12/24/48 V is

option 1.
All new batteries 1600 ah 24 or 48 V system ( batteries 24 or 48, inverter to match ) 400 ah remains in 12 V for navigation lights and electronics and the rest of the boat pumps lights circulating fans. Many options for inverter

Option 2. All new batteries all in 12v use victron 2 5kw or 1 10 kw. Victron only option for the 12v
 
Anyone out there ?? I guess I will assimilate and continue on with all 12v. All the wiring is here why change it? Why run at 48v or 24v?
 
If you are converting to Lithium and don't know much about it, this is a must read:
His recommendations are high end and pretty pricy, plenty of people do it cheaper than his recommendations. But you need to know the issues. His recommendations for the higher priced stuff comes from experience.

You need to do any energy audit. Nothing else can be determined until that. 2000Ah of Lithium is an insane amount of power for most boats (is this a superyacht?) 2000Ah of Lithium is roughly equivalent to 4000Ah of Lead. You have 800Ah of Lead now. Do you really need 5x as much capacity?

12 vs 24 vs 48 volts is best determined by how many watts you need. 24 or 48 volts allows smaller wire when you start needing higher watts. But if you aren't using 4000W, you don't need 24 or 48 volts. All of this comes from an energy audit.
 
First of , thank you for the Reply.
“Do you really need 5x as much capacity?” I want to run a 12v system 400 ah ( 2 battery) this system will handle marine fridge and freezer, windlass and all electronics aboard. Then a 48v or 24v 1600 AH ( 8 battery) solely for the 110 Ac panel. There is 3 AC 12,000 btu x 2, 1600 btu , 4 bathroom, a fly bridge and we converted to all electric cooking because it’s renewable source. Electric stove, cook top and bbq. BBQ and cook top on fly bridge too.
 
AC is a large load, and would benefit from 24V or 48V. If my calculations are correct: 25,600btu = 7500Wh
to run for 5 hours per day = 37,500Wh
For 48V that is 780Ah
For 12V that is 3125Ah
So even with more AC than I have ever seen on any boat (excepting superyachts) , 2000Ah of 48V Lithium is more than 2x what you need to run it all at the same time for 5 hours. Solar is another issue. 37,500Wh / 5 hours of daylight would require 7.5kW of solar to produce that power. To account for cloudy days etc., you would be wise to double that. I suggest halfling the size of the lithium bank, and adding a reliable generator. The generator can run the AC, and charge the Lithium simultaneously. This is a very large and complex install, not a few simple connections. You would be wise to pay a few thousand to a competent marine electrician, at least to plan it all and determine what you need and give you drawings how to hook it up. It sounds like you have a very large and nice boat. It would be a shame for it to catch fire and burn because you wanted to save a couple thousand dollars.
 
We would only run one thing at a time. Port AC then salon AC separate.
We don’t want to save thousands but we don’t want to throw away money either. That said I can’t find anyone to assist me if it’s not 12v. Sucks when you have the idea and can’t find the help. What is happens to this world ? Anyway I’ll keep searching for a competent knowledgeable electrician in Florida south east coast. No burns or fires here sorry.
 
What kind of boat do you own (sailboat or power)? I can only comment for sailboats, so here are my 2 cents:

12V vs 24V vs 48V
There are 2 main reasons for deciding on this:
  1. The higher the voltage, the lower the wattage and the smaller the wire diameter. This is mainly a cost factor, but also see nr2.
  2. What equipment will be running on the voltage. 12V is pretty standard, but so is 24V. 48V is more rare on a sailboat as almost no equipment runs on 48V. Winches, Windlass, watermaker... often are 12V or 24V. If you're planning a new system, I would recommend 24V.
  3. If you don't run any equipment on the lower voltage (12/24/48) and are just planning on using an inverter to 240V/110V, than go for the 48V battery system. Lower voltages won't make any sense. You could even make a 240V battery system, but you'll probably have 1 big battery, instead of multiple in parallel. The latter gives you redundancy in case 1 pack fails.
Equipment:
In Europe Victron is pretty popular and rock solid equipment. They have inverters up till 48V and you can use them in parallel to get to the required wattage. Go for the Multiplus or a Quattro in case you also run a generator.

Battery size:
Most people will say size is related to consumption, but I mostly look at power generation. The size must match your chargers / solar MPPT's. I doesn't make any sense to have a 2000Ah battery and a 60A charger. Even solar is pretty weak to charge such a battery. I have a 720Ah 24V battery and have 100A alternator (7hrs running time to fully charge) and 220A chargers (3hrs running time). I even didn't consider solar because I have a generator on board.

Shore power is another issue as eg in Europe the breakers on the dock are often 16A @ 240V = 3840W. On a 24V system, you'll trip them if you go over 160A charging power. Even more bad news: LiFePO4 batteries have almost no internal resistance, so the draw will be max during the full charging time. Luckily the Quattro lets you limit the power draw from shore.

As a side note: also look at your alternator because it will probably overheat when switching to LiFePO4 because of their low internal resistance. You'll either need a DC/DC inverter or use field regulation (Wakespeed, Balmar).

Do read the article the is mentioned in a post from wholybee. It has very good information.
 
Good day guys I have a boat system that need updating.
currently I have 800ah 4 year old lead acid, 1.7 kw panels @ 285 x6
2 x 2000W inverter
2 c Outback Flex 80
60 A shore power battery charger Xantrex

so far I have the batteries 2000ah lip04
I will keep the outback’s if I don’t go with an all in one inverter

I am ditxhing the lead acid batteries and inverters.

i have bifacials panels in my cart and ready to swap out for my current panels but i am stuck on the fact that they will over hang 12inch from the boat roof and if the current installment bolts will work for the bifacials as the panels are the same width just longer on length. I will also be adding 111 lbs extra to the roof.

My mind is set on an all in one that makes everything much much easier.
I am new to lithium and solar but have been reading along for about a year.
Anyone I ask for their input that’s a marine electrician has no idea what i am doing and quotes me for 2-10k to assist with simple final connections.
My very easy plan other then swapping panels and choosing inverter all in one or victron 12/24/48 V is

option 1.
All new batteries 1600 ah 24 or 48 V system ( batteries 24 or 48, inverter to match ) 400 ah remains in 12 V for navigation lights and electronics and the rest of the boat pumps lights circulating fans. Many options for inverter

Option 2. All new batteries all in 12v use victron 2 5kw or 1 10 kw. Victron only option for the 12v
Option 1 or 2 is a MASSIVE difference in battery capacity...
2000AH at 12 v is 25,600 Wh and 20 400Ah lithium cells...

2000Ah at 24V is 51,200Wh and 40 400Ah cells...

2000Ah at 48V is 102,400Wh and 80 400Ah cells...
 
What kind of boat do you own (sailboat or power)? I can only comment for sailboats, so here are my 2 cents:

12V vs 24V vs 48V
There are 2 main reasons for deciding on this:
  1. The higher the voltage, the lower the wattage and the smaller the wire diameter. This is mainly a cost factor, but also see nr2.
  2. What equipment will be running on the voltage. 12V is pretty standard, but so is 24V. 48V is more rare on a sailboat as almost no equipment runs on 48V. Winches, Windlass, watermaker... often are 12V or 24V. If you're planning a new system, I would recommend 24V.
  3. If you don't run any equipment on the lower voltage (12/24/48) and are just planning on using an inverter to 240V/110V, than go for the 48V battery system. Lower voltages won't make any sense. You could even make a 240V battery system, but you'll probably have 1 big battery, instead of multiple in parallel. The latter gives you redundancy in case 1 pack fails.
Equipment:
In Europe Victron is pretty popular and rock solid equipment. They have inverters up till 48V and you can use them in parallel to get to the required wattage. Go for the Multiplus or a Quattro in case you also run a generator.

Battery size:
Most people will say size is related to consumption, but I mostly look at power generation. The size must match your chargers / solar MPPT's. I doesn't make any sense to have a 2000Ah battery and a 60A charger. Even solar is pretty weak to charge such a battery. I have a 720Ah 24V battery and have 100A alternator (7hrs running time to fully charge) and 220A chargers (3hrs running time). I even didn't consider solar because I have a generator on board.

Shore power is another issue as eg in Europe the breakers on the dock are often 16A @ 240V = 3840W. On a 24V system, you'll trip them if you go over 160A charging power. Even more bad news: LiFePO4 batteries have almost no internal resistance, so the draw will be max during the full charging time. Luckily the Quattro lets you limit the power draw from shore.

As a side note: also look at your alternator because it will probably overheat when switching to LiFePO4 because of their low internal resistance. You'll either need a DC/DC inverter or use field regulation (Wakespeed, Balmar).

Do read the article the is mentioned in a post from wholybee. It has very good information.
Great 2 cents. Thank you very much.
I must be more clear for you guys. The boat needs 12v system. And I will still have that. 400 ahr 12v system that only powers DC boat appliances like fridge freezer ( marine extremely inefficient) windlass when needed and lights fans and pumps. I need a way to charge the 12v lithium from option 1 engines - need to modify alternators ; option 2. Charge from solar option 3. Charge from larger 48v battery bank and option 4. Charge from a 12v battery charger ( I currently have a Xantrex 12v 60ah but Xantrex said it won’t work for lipo) ideally I will have dc to dc setup ( anyone done this before and have recommendations?) and backup to charge from generator leaving option 1 the engines to Maintain the engine batteries only and option 2 solar to charge the 48v larger bank.

The 48v bank 1600 ahr is solely for the 110 pane on the boat and charging the 12v when necessary! It will run AC, water maker, pressure washer, hooka diver and all 110 items running during the day like fridge and small freezer 110v super cheap and really efficient to use. The 48v will have an all in one inverter with generator input shore power input and the out put will be to a shore power cable. My panel is setup for shore power so I am going to give it shore power from the compliments of my boat. We don’t plan on running multiple things at one time. We already don’t use a-lot of power on the dock. Using aC only at night and monitoring power consumption.
 
If you're at the dock and on shore power...why?

I'd suggest hiring Jeff Cote(?) From pacific yacht systems. Search him on YouTube.com. the dude has forgotten more about electrical systems on boats than most will ever know.
 
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