Charging LiFePo4 Batteries With Just Solar

Jan 11, 2014
13,385
Sabre 362 113 Fair Haven, NY
I'm also not sure about the ramp times, but was of the impression it is programed into the Wakespeed. But as I've said, I'm not knowledgeable enough to know how they all work in these details.
If I recall correctly the ramp up time can be programmed within certain limits.
 
Nov 20, 2025
20
Alden 60' Schooner Killybegs
My philosophy is to equip a boat to meet the needs of 80% of my sailing outings and for the other 20% I make adjustments and may temporarily carry additional equipment. Too often I see boaters equip their boat for crossing oceans when all they do is weekend trips.
This is exactly the right approach and it applies to crossing oceans, too, maybe even more so. When talking about electricity, the wise approach isn't trying to figure out how to get just a bit more power output, but figuring out how to use a bit less of it. Living within your means is always important, but in the middle of the Pacific with less wind than expected for days, it can mean life or death.

Ask me about the time I thought I needed a watermaker. My hubris and overconfidence in technology made me and 5 crew members very sick.

The better answer is rarely to add more equipment. I see more people thinking they need a fridge. Then they need to be able to power that fridge. But, if that fridge dies in the middle of a crossing, you better not be relying on the food in that fridge. And, if you weren't relying on the food in the fridge, why did you need the fridge in the first place?

It's like people who work at fancy jobs in the city so they can afford a house in the city and a car so they can get to the job and clothes that they need for the fancy job.

On the boat, the first question should never be, "What do I need to add?" it should be, "What can I remove?" Everything you add comes with hidden costs, headaches, and dependencies. On our boat, we call it the "one minus two" rule. Every decision to bring something new on the board needs to eliminate the need for two other things. It's obviously not a literal calculation - just a philosophical guideline. I see many people who seem to prefer the "one plus two" rule.

We still don't know what the General plans to do, unless he explained it somewhere else. It doesn't really matter. He was just looking to confirm some estimates and I think he's done that. I trust he'll apply that information in a way that suits his needs.
 

colemj

.
Jul 13, 2004
795
Dolphin Catamaran Dolphin 460 Mystic, CT
That's good advice if one wants to sail alone and rot in their own sweat eating canned beans. These people represent maybe at most 0.5% of the people we have ever met out cruising in the past 17yrs, and that 0.5% were not really even cruising.

"Comfort" systems have come a LONG way in terms of power usage and robustness from the 1970's mindset. It's like telling someone who lives off-grid to forgo refrigeration and an electric pump on their well because those could break.

Sure, things break occasionally, and one must have contingency plans or backups, and definitely have some idea how to troubleshoot and solve issues, but to just forgo stuff to remove the possibility of breakage is silly. Might as well say the same thing about the rudder, or sails, or rigging, etc.

Mark
 
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dLj

.
Mar 23, 2017
4,728
Belliure 41 Back in the Chesapeake
This is exactly the right approach and it applies to crossing oceans, too, maybe even more so. When talking about electricity, the wise approach isn't trying to figure out how to get just a bit more power output, but figuring out how to use a bit less of it. Living within your means is always important, but in the middle of the Pacific with less wind than expected for days, it can mean life or death.

Ask me about the time I thought I needed a watermaker. My hubris and overconfidence in technology made me and 5 crew members very sick.

The better answer is rarely to add more equipment. I see more people thinking they need a fridge. Then they need to be able to power that fridge. But, if that fridge dies in the middle of a crossing, you better not be relying on the food in that fridge. And, if you weren't relying on the food in the fridge, why did you need the fridge in the first place?

It's like people who work at fancy jobs in the city so they can afford a house in the city and a car so they can get to the job and clothes that they need for the fancy job.

On the boat, the first question should never be, "What do I need to add?" it should be, "What can I remove?" Everything you add comes with hidden costs, headaches, and dependencies. On our boat, we call it the "one minus two" rule. Every decision to bring something new on the board needs to eliminate the need for two other things. It's obviously not a literal calculation - just a philosophical guideline. I see many people who seem to prefer the "one plus two" rule.

We still don't know what the General plans to do, unless he explained it somewhere else. It doesn't really matter. He was just looking to confirm some estimates and I think he's done that. I trust he'll apply that information in a way that suits his needs.
His plans were stated in an earlier thread, I reposted it in this thread in post #13.

While I absolutely agree many people put on more and more gadgets that our marketing world says we "need" - most we don't.

I'm not a gadgets lover. I like simple, robust and easy to repair if necessary. I tend to only put on systems I can repair - there are exceptions. For example, I probably can't fix my RADAR other than some simple connection issues, but since I sail where it's pretty much a necessity - I'm keeping it, and I'll send it in for routine maintenance when needed.

My first ocean capable boat had no refrigeration, no GPS (it didn't exist) and not much more than navigation lights for electrical. I didn't even need electric to start my engine as it could be hand cranked. That's not possible on my current boat.

Everyone has different comfort level needs/desires. I also find as I get older, I prefer more comfort.

I'm not throwing out my GPS navigation systems and going back to navigating by sextant. There are very few currently doing that - I know of no one personally.

As time goes on, we learn more about how to make systems more robust. A lot of the discussion here has been about basic design and what would work better for the OP with his stated purpose.

dj
 
Nov 20, 2025
20
Alden 60' Schooner Killybegs
That's good advice if one wants to sail alone and rot in their own sweat eating canned beans. These people represent maybe at most 0.5% of the people we have ever met out cruising in the past 17yrs, and that 0.5% were not really even cruising.

"Comfort" systems have come a LONG way in terms of power usage and robustness from the 1970's mindset.
I think you've made some pretty big leaps there and too many assumptions. I rarely sail alone, don't rot in my own sweat, nor eat canned anything, as a rule. You can sail in comfort and style by either adding equipment or by improving your knowledge and skills. The former is less sustainable and no substitute for the latter though, increasingly, it is treated as such.

I’ve shared oceans with every flavour of sailor - from the ascetics boiling lentils on a paraffin stove to the folks with more lithium than sense. None of them were wrong, they just built their boats around the sort of life they wanted to live.

My point wasn’t “strip the boat bare and martyr yourself.” Comfort’s grand. It is just that every piece of equipment brings weight, heat, wiring, spares, failure modes, and troubleshooting you’ll be doing when you’re cold, tired, and days from a calm anchorage. It is important to make sure it is pulling its own weight and gives more than it takes. That's not me lamenting a bygone era. That's me having sailed tens of thousands of miles with it both ways and expressing a well-earned viewpoint.

We're getting well off-track from what the General was asking, but folk compare a broken pump to a broken rudder as if they’re the same sort of problem. A rudder is existential; a watermaker that goes sulky is just inconvenient. But if you’ve built the whole rhythm of your life around that machine, you’ve made it existential by choice.

Seamanship to me is matching the boat to your temperament. If someone wants all the mod cons and is willing to maintain them, fair play. The world’s full of good anchorages with solar arrays glittering like armour. But there’s an unseen tax to complexity, and I’ve paid it enough times that I’ve learned to ask myself a simple question before adding anything: “Will this make my life better, or will it just make the boat better?”

Sometimes the answer is yes, bolt it on. But, on Aisling with a crew of usually somewhere between 4 and 6, we are well-rested, eat like royalty, and do not uncleanliness. And, we do this without a generator, fridge, AC, auto-pilot, or most of the other equipment that are increasingly considered must-have.

That’s the bit I’m arguing for - not austerity, just awareness and seamanship. Simplify where you can so the things you choose to keep actually serve the crew and not the other way around.

Comfort is lovely. Capability is better. Experience buys you both.

With respect, having only cruised for 17 years, you have probably only ever known it one way.

With regards to the General's actual question, though, my advice stands - focus on minimizing consumption, then design your production around that, rather than the other way around.
 

dLj

.
Mar 23, 2017
4,728
Belliure 41 Back in the Chesapeake
And, we do this without <snipe> auto-pilot <snipe>
Good lord, I'm done running without either my windvane or an autopilot... Sorry, that's just not for me. I've hand steered enough times to know I'm going to have a machine doing that for me... If I'm running by wind - I'm running by windvane. If I'm running by motor - I'm running my autopilot (well for legs, certainly not coming into harbors...)

dj
 

colemj

.
Jul 13, 2004
795
Dolphin Catamaran Dolphin 460 Mystic, CT
You can sail in comfort and style by either adding equipment or by improving your knowledge and skills. The former is less sustainable and no substitute for the latter though, increasingly, it is treated as such.
And here is where you tip your hand as a pedantic. Adding equipment and improving knowledge/skills are not mutually exclusive. Only someone with a strong fixed bias would think so.

Even simple logic fails to support you. Most people have more knowledge and skills by using GPS, AIS, and radar for navigation than those who do not. They are definitely more safe to themselves and others. Don't fall into the trap of "I know how to use a sextant, so I am a superiorly skilled navigator". That is BS equivalent to thinking that using resin-impregnated cloth wire insulation and bakelite fixtures is superior to modern electrical installations. Because we have a watermaker, our boat gets a complete wash down after every passage, and another every few days. This is good boatmanship, as it keeps corrosion and chafe at bay. Thanks to "unnecessary equipment", we have 4 different ways of getting immediate, extensive, and up-to-date weather data (5 if I counted coastal VHF weather).

I suppose if I had a 60' boat with a crew of 6, then there would be sufficient tankage and dry food storage space to forgo a watermaker and refrigerator. But even you would have trouble cruising in someplace like the Tuamotas or Bahama out islands or many other places for 4 months where there is no water, little rain, and scarce food supply.

Is your wife or girlfriend on the boat with you for long passages and extended times? I've met few who would live a long time on board without a refrigerator and enough water to use pretty freely. I've met few men who would. Particularly any older than their 30's.

FWIW, I've been sailing/cruising for 50yrs, with most of that time being in very basic boats. While the past 17yrs of full-time cruising might be a pittance, if one adheres to the belief that 30yrs is the minimum for experience, then one has given up the game. I don't want to wait until I'm staring down death in a couple of years to consider myself sufficiently experienced.

The flip side of that is 30yrs of cruising in one particular style and belief system means new thinking and technology passes right over one without recognition or appreciation. I experience this, as younger cruisers today are all wrapped up in social media whose purpose and use I don't fully understand. But I do recognize that it is something new now that is improving all aspects of their cruising life, knowledge, and skills.

Mark
 

colemj

.
Jul 13, 2004
795
Dolphin Catamaran Dolphin 460 Mystic, CT
Good lord, I'm done running without either my windvane or an autopilot... Sorry, that's just not for me. I've hand steered enough times to know I'm going to have a machine doing that for me... If I'm running by wind - I'm running by windvane. If I'm running by motor - I'm running my autopilot (well for legs, certainly not coming into harbors...)

dj
You don't have a crew of 6.

Mark
 

dLj

.
Mar 23, 2017
4,728
Belliure 41 Back in the Chesapeake
You don't have a crew of 6.

Mark
Hahaha - true that! But even if I did - I wouldn't subject them to sitting on the tiller (or wheel) for an entire shift, however one defines a shift...

dj
 
Nov 20, 2025
20
Alden 60' Schooner Killybegs
And here is where you tip your hand as a pedantic. Adding equipment and improving knowledge/skills are not mutually exclusive. Only someone with a strong fixed bias would think so.

Even simple logic fails to support you. Most people have more knowledge and skills by using GPS, AIS, and radar for navigation than those who do not. They are definitely more safe to themselves and others. Don't fall into the trap of "I know how to use a sextant, so I am a superiorly skilled navigator". That is BS equivalent to thinking that using resin-impregnated cloth wire insulation and bakelite fixtures is superior to modern electrical installations. Because we have a watermaker, our boat gets a complete wash down after every passage, and another every few days. This is good boatmanship, as it keeps corrosion and chafe at bay. Thanks to "unnecessary equipment", we have 4 different ways of getting immediate, extensive, and up-to-date weather data (5 if I counted coastal VHF weather).

I suppose if I had a 60' boat with a crew of 6, then there would be sufficient tankage and dry food storage space to forgo a watermaker and refrigerator. But even you would have trouble cruising in someplace like the Tuamotas or Bahama out islands or many other places for 4 months where there is no water, little rain, and scarce food supply.

Is your wife or girlfriend on the boat with you for long passages and extended times? I've met few who would live a long time on board without a refrigerator and enough water to use pretty freely. I've met few men who would. Particularly any older than their 30's.

FWIW, I've been sailing/cruising for 50yrs, with most of that time being in very basic boats. While the past 17yrs of full-time cruising might be a pittance, if one adheres to the belief that 30yrs is the minimum for experience, then one has given up the game. I don't want to wait until I'm staring down death in a couple of years to consider myself sufficiently experienced.

The flip side of that is 30yrs of cruising in one particular style and belief system means new thinking and technology passes right over one without recognition or appreciation. I experience this, as younger cruisers today are all wrapped up in social media whose purpose and use I don't fully understand. But I do recognize that it is something new now that is improving all aspects of their cruising life, knowledge, and skills.
I'm not sure who you're arguing against, but it sure isn't me. You've constructed a straw man.

I think I summed up my position in my last post, but it looks like you've got something else on your mind.
 
Nov 20, 2025
20
Alden 60' Schooner Killybegs
But even if I did - I wouldn't subject them to sitting on the tiller (or wheel) for an entire shift, however one defines a shift...
Well, I thought my crew were healthy and happy, but between you and Mark I've come to realize that they are dirty, malnourished, and endure tortuous duties. Thanks for the warm welcome.

Well, to be fair, I was warned before I joined.
 
Mar 26, 2011
3,823
Corsair F-24 MK I Deale, MD
Boy are we off topic.

My PDQ had heat, AC (could run off solar), full nav, galley (propane), hot water (propane), and refrigeration (propane), without an diesel or generator. I did not hand steer much. It's all about system design and sometimes useage. For example, you don't run AC when there is wind. If there was no wind even the outboards put out enough to run the pilot, what we needed, and charge a little.

No canned beans; good cooking was a highlight. But I might use retained heat cooking, mostly to save heat in the galley and to avoid watching the pot. If it was hot I would often take a room temperature shower on the swim platform because it was more comfortable and refreshing than hot an humid in the cabin.

There is a difference between living high-carbon like at home, thinking things through, or just suffering. The middle path. As cheap as solar has become, running a generator (or diesel for charging) just seems weird to me. Noise.
 

dLj

.
Mar 23, 2017
4,728
Belliure 41 Back in the Chesapeake
Well, I thought my crew were healthy and happy, but between you and Mark I've come to realize that they are dirty, malnourished, and endure tortuous duties. Thanks for the warm welcome.

Well, to be fair, I was warned before I joined.
@Cap'n Deke I'm not sure what you are looking for in a warm welcome. On my side, if I wasn't welcoming, I wouldn't even address anything you write. I'd ignore you.

You also don't seem to have read what I wrote.

I said absolutely nothing about your crew or your boat. I stated that I would not run without an autopilot/windvane.

dj