New Generator or Lithium?

[Budawang]

Originally Posted by HankOnthewater

Hi Budawang
First about using engine to charge batteries. I am with Westclif01: get a good large alternator on your engine first, assuming you can convert your existing setup (I assume with single V-belt) to a double V belt or better still: a serpentine belt. Doing that you can shop around for a 100- 200 Amp alternator, that in reality will max out at ~half those amps and only when the batteries are low.
The cost for doing that conversion is still likely to be $2k to $3k; you need also a regulator, ie Balmar 612, 614 or 615. https://www.outbackmarine.com.au/pow...es-alternator/
And when you have to run your engine to charge the batteries, do that early in the morning when the batteries are their lowest, and will accept the highest charge current.

Next is solarpanels: I think everyone agrees that maximising the acreage of panels is good. The only drawbacks are aesthetics and actual suitable places. Note that windgen, rigging, mast, sails etc all shade the panels at times, and then reduce their output, often more than 50%.

Then batteries. Yes, Lithium is the trend, and the technology is there. But there is inherent complexity to use lithium with existing systems: ie does your current solar charger has settings for it? How do you charge it from your alternator(s)? I doubt if your Rutland windgen controller is suitable for lithium.

The benefits for lithium are: #1 lighter, #2 smaller, #3 many more charge cycles, and #4 acceptance of high charge and discharge currents. Benefit #1 and #2 may not really apply in your case as you have a heavy displacement boat, benefit #4 is not really important as even with a 100 Amp alternator, it will quickly overheat the alternator delivering the high currents that are close to the max of that alternator. To deliver currents of 100 amp plus, one would need a 230 Volt genset with a coupled charger, or a 200 amp alternator on engine.
Then the negatives of lithium start to play a role: price and complexity. Price is simple, you either have the $$ and prepared to spend, or stick with LA (lead acid) or AGM. The cheapest lithium is one of those drop in batteries 100 Amp/hr and all is well…….. if you believe the marketing of these products, or ….. spend considerable more $$$ and have a system designed for your boat, with proper BMS (battery management system), DC to DC charger(s) etc. In one of the above posts there some links, here is another one from a reputable business: https://www.evworks.com.au/ Or some info on Lithium on boats: Benefits and challenges with using lithium batteries on board | Nordkyn Design
But…….I have not seen a lithium system that can be described as ‘simple and robust’.

My gut feeling neither your options “generator or lithium” is favourable, but a combination of a larger engine alternator, maximising solar, new LA or AGM batteries, maybe carry a small inverter type of genset like the Honda EU 2200i as backup. Note when using such gennie, you need a proper 230 Volt charger for that. If you have an inverter/charger than that charger might be big enough.
The savings you make by not buying lithium or a large diesel genset, might fund all these additional equipment. Because whatever you do, you have to buy new batteries.

Of course you can always buy a secondhand generator. Or at times I see little diesel engines that drive a large 12 Volt alternator (ie 200 to 400 amps). I can not think of any supplier that sells these new at the moment. Balmar had a unit (AP 750) and Amplepower had some models as well (hmm their website is not working at the moment) or here are some links with more info on such subject:
https://www.cruisersforum.com/forums...-go-65703.html
https://marinehowto.com/category/electrical/
Such small engine would diminish the need to run your main engine, just to provide charging power for your batteries, and then you have not have to upgrade your main engine charging system.

Some other comments:
quote: Our AC usage has included powering a microwave, electric kettle, small hot water tank, small space heater and laptops. We are part time cruisers and like living on the hook.
I would say that running these (in red) on batteries is not recommended, and an electric kettle might be OK, but your planned inverter of 2000 Watt is marginal as most kettles are 2000 to 2400 Watts.
But really the biggest issue is not running all these from your batteries, but finding methods of recharging the batteries.

You said in post #6 that your capacity for recharging is currently (without genset) 220 amp/hr a day. I did not see any daily energy usage. Hmmm, noticed some other posters took that number of 220 as your daily usage…. But assuming that your daily charging capacity is that 220, then your actual usage should be less than that. A lot less, if you have days of not little charging. I would think your usage could be a lot more, particularly when under way with autopilot.

Again assuming your usage is around that figure, then as it has been said in this thread before, your battery bank should be at least 600 Amp/hr using AL or AGM, and 300-400 Amp/hr using lithium.
There are countless spreadsheets how to calculate your electricity use.
Like this one (picked at random from the net): https://www.sailboat-cruising.com/boat-electrics.html
Or I can email you the spreadsheet I have been using
Yours, in kindred spirit 😊

G'day Hank. Thanks for the thoughtful and informed response. I like your reference to "gut feeling" because, at the end of the day, intuition does count for something when there's such an array of often complex options. Yes, many people are unconvinced of lithium's cost benefit ratio although those that have invested in it often sing its praises with evangelical zeal

I saw a boat last year that had an Chinese diesel generator that cost a fraction of the cost of the big name makes. Seemed to work just fine, including directly running a b ig fridge compressor twice a day It was impressive, but I have no idea how to source something like that let alone install it. A Honda eu2200 might be the go, but it would be a bit of a hassle running it on deck on a regular basis, they are noisy and we are short of storage space.

We have a Victron 60 amp charger that's programmable for lithium. I'm also intrigued by the Amptron (Perth company) LifePO4s as they are surprisingly affordable at about $900 (Australian) per 100 AH, barely double that of a good AGM and almost the same upfront cost when you compare "useable" storage. Amptron seem to have a good reputation for quality as far as I can tell. That famous 4xOverland guy Andrew St Pierre White recently chose them for his "dream camper".

Please do send me a copy of your spreadsheet - thanks. I need to get a better understanding of our daily usage. I'm guessing it's around 150 AH but would be a lot more when we're doing passages under sail.

Hope you're riding out the global "tempest" with flying colours.

[Budawang]

Originally Posted by downunder

I have been looking at lithium systems for some time and certainly the Aussie manufacturers are up there. Their drop ins which have onboard BMS's may well make lithium easier for non electricians like myself.

This guy has some interesting info on drop in lithiums

Cool videos, thanks. You might like this:

https://www.youtube.com/watch?v=nH7XmprkbOM

[blinkerfluid]

Originally Posted by a64pilot

See, I don’t believe the numbers, I don’t believe LA are dead in 500 cycles, as that’s a year and a half and people aren’t buying batteries every year and a half, and I don’t believe the LFP cycles either.
Maybe if you use only the middle third of capacity, that greatly extends life, but cuts capacity way down. For example the Toyota Prius we have will only discharge down to 40% SOC and won’t charge above 80% SOC, 40 and 80 are displayed as full and empty, but noting cycles batteries like a hybrid, driving around town with the AC on, your cycling several times an hour.

I believe the marketing dept has determined LFP cycle life, you know the same ones that would sell me a 500W car stereo that has a 10 amp fuse in its power wire.

I'm sure people aren't replacing their batteries every year and a half.. I'm also sure the vast majority of people don't discharge their battery banks to 50% everyday either. Peace, I'm not trying to sell you or anyone else on Lithium; I'm simply showing what we chose to do on our own boat.

[blinkerfluid]

Originally Posted by Budawang

It's good to hear from someone in the same situation as us with a similar sized boat. My current thinking for going with 2x160 amp/hr is that we aren't very big power users and it would still be a big improvement on our existing 330 amp/hrs of lead acid storage. At least 60% more useable power if I'm not mistaken. We also need enough power charging sources to match our storage and, without a generator, we will be dependent on wind, solar and existing 100 amp alternator (with regulator to avoid destroying it).

I'd be interested to know why you decided to go for 600 amp/hrs LifePo4. Do you have particular large energy requirements?

The biggest reason I went with a big lithium bank is that we have an electric galley. We removed the propane system from inside our boat and installed an induction cooktop and microwave/convection oven combo. Plus my wife really likes her coffee and I want to make things easy for her (regular coffee pot is easy). We also have 1 fridge and 2 fridge/freezers. We went with a big bank to have the energy reserves for an electric galley, and we went with lithium so we didn't have to deal with voltage drop and reduced battery capacity for high current draws.

[noelex 77]

As others have pointed out, batteries store rather than produce power.

Unfortunately, with your current solar system, wind and alternator, you will not meet your likely power demand without a generator. The microwave, electric kettle and small hot water tank in particular are reasonably high power demand appliances and running these appliances consistently is likely to exceed your production.

Before making any permanent changes I would suggest measuring your typical power consumption. It is hard to make predictions without accurate information. If you are planning to do without a generator, then a good battery monitor is an important component.

[sailingchiro]

Southern Cross marine salvage had one of those farryman gensets for not much money and it was running. They are located in Pensacola.

[zboss]

Originally Posted by a64pilot

I think alternator, regulator and serpentine belt kit which you will need if your going to pull 100 amps is about $ 2,000 I think.
Honda is $1,000 and doesn’t take away hours on your propulsion motor.

It is hard to argue with a Honda generator for a smaller vessel with moderate energy needs. We have spent many years using the Honda with much success. It does create a lot of noise and there are safety issues you need to keep in mind. Its easy to service and pretty much any small engine repair place can work on it if you can't fix it yourself.

I do think that the addition of a large alternator has value, although financially it is a bigger bite.

We have a 165A Balmar and when we are actively cruising we can put a whole lot of juice into depleted batteries in the 20-30 minutes it takes to get the engine on, bring up the anchor, rinse it off, and get out of the anchorage. Same for the end of the day when you are coming into an anchorage. When you are on passage you can run the engine for an hour or two to charge up the batteries at night and get a little boost at the same time.

The problem with the Golf Cart batteries is that when they die, they die fast. There were a bunch of boats in the Bahamas this past season that had their end-of-life batteries die very quickly once they were regularly at anchor and working off solar alone. You need to proactively change them if it appears its time - before you end up in a place like the bahamas where they charge $300 for a battery.

[Dockhead]

You've gotten a lot of good advice, a lot of which is contradictory. Up to you choose what sounds right. There are a lot of different ways to skin this particular cat.



At the risk of not saying anything necessarily new, I would just add:


1. Lithium vs. lead acid really depends on how much you are using the batteries. If you are off grid a lot and cycling the batteries A LOT, then lithium will pay for itself. so not only better, but actually cheaper, as the cost per cycle is less IF you cycle enough to be wearing out lead acid batteries more often than say every 5 years. And lithium is much BETTER, works better, is more efficient, less hassle. So I think it's not at all dumb to be considering this.


2. If you go lithium, don't use the pre-made drop in conversion units. They are costly and the only point is to avoid converting your charge and management infracture. Better bite the bullet and do the conversion, and by raw cells. Lot of information in this forum how to do it.


3. If you go lead acid, then go with golf cart batteries (Troject T105 or whatever). Quite robust, yet cheap.



4. Make sure you have good battery monitoring and management even for lead acid. You especially want a top notch charger (which maybe part of an inverter charger).


5. Do upgrade the alternator whether or not you replace the generator. Just use a plain old school bus alternator, e.g. Leece Neville -- cheap and good. Add external regulator like Balmar. You especially want the external regulator if you choose an alternator big enough that you might bog down the engine at certain RPM's when you're using it for propulsion. The Balmar allows you to dial down the power using a switch at the helm.


6. More solar? There's kind of no such thing as too much solar PROVIDED you have space for it and you are not causing too much windage. Be careful about the second question if you are a keen sailor.


7. Replace generator? You might really not need to with both a heavy duty alternator AND a fair amount of solar. But if you, look at the cheap and good ones from NexGen and Phasor. Or a DC generator.



8. Oh, and don't let inverter efficiency drive a decision to be DC or AC or do without an AC generator. Tail wagging the dog. Inverters are efficient enough.

[CarlF]

Another person with Fireflys and a big alternator on a serpentine belt - very happy.

You’ll be much happier with a 600 amp/hr house bank - or even 800

I chose Fireflys instead of Lithium because Lithium on boats is still a bit “bleeding edge”. The lithium technology on boats is still maturing and there are lots of different opinions about how to do it. Manufacturers come and go. It’s not as simple as dropping in a new battery. The Fireflys can be discharged to 80% repeatedly without damage. In actual use I rarely discharge more than 60% but it’s nice not to worry.

My engine has two alternators. The small one that came with it and a big Balmar 200 amp on a separate serpentine belt attached to the crank shaft. These are pretty simple for a good shop to fabricate. . This provides redundancy should one fail. I use a Balmar regulator that lets me set the belt load to reduce belt wear and ease the load on the engine. The alternator is a “large case” alternator. They don’t lose charging amps nearly as quickly from heat as a small case alternator (small case deliver less than half their rated amps after a short time).

Unless you enjoy anchoring in unprotected area, I would save money and skip the wind generator. These provide almost no power below 15kts. Your 50 amp/hr assumption is unlikely. Get a few more solar panels with the money.

[mvweebles]

Originally Posted by Budawang

I have a choice to make. Our 18 year old Farymann 18 W single cylinder 4 kva diesel generator has a compression problem and I can't find parts to fix it. Instead of buying an expensive new generator I'm considering biting the bullet and upgrading our batteries to 400 amp hour LiPo4s with a 2,000 watt inverter. For charging we will have a Rutland wind generator, 300 watts solar and a 100 amp alternator with its own regulator. Our existing lead acid batteries (330 amp hour house bank) are nearing the end of their life but we probably would have replaced them with AGMs if the generator was still working.

Our AC usage has included powering a microwave, electric kettle, small hot water tank, small space heater and laptops. We are part time cruisers and like living on the hook.

I understand it wouldn't be sensible to run a space heater off a lithium bank, but does the above set-up sound like a rational alternative to buying a new generator?

Your water heater may push you over the edge, but otherwise, yes, good setup.

For general budgeting, your solar will generate round 125AH/day. Consumption:
- Microwave takes about 6AH for 5-mins of runtime
- Electric kettle takes around 9AH for 5-mins of runtime
- PCs consume around 2AH per hour of run/charge, so figure 10-15AH/day each
- You didn't mention refrigeration, but that's around 35-40 AH/day
- Ambient lighting - around 10AH/day

All-in, you should be around 100AH energy budget if you're careful; 125-150AH if not. 400AH of battery and 125AH solar will get you dang close to off-grid, if not comfortably so. From there, you can tinker with bigger alternator, regulator, Honda gen, etc.

This really isn't that complicated. Solar, 100A Alternator (FYI - will rarely run more than 50A). It's a good setup for you - my guess is you'll wish you did it long ago.

Peter

[Budawang]

Originally Posted by zboss

It is hard to argue with a Honda generator for a smaller vessel with moderate energy needs. We have spent many years using the Honda with much success. It does create a lot of noise and there are safety issues you need to keep in mind. Its easy to service and pretty much any small engine repair place can work on it if you can't fix it yourself.

I do think that the addition of a large alternator has value, although financially it is a bigger bite.

We have a 165A Balmar and when we are actively cruising we can put a whole lot of juice into depleted batteries in the 20-30 minutes it takes to get the engine on, bring up the anchor, rinse it off, and get out of the anchorage. Same for the end of the day when you are coming into an anchorage. When you are on passage you can run the engine for an hour or two to charge up the batteries at night and get a little boost at the same time.

The problem with the Golf Cart batteries is that when they die, they die fast. There were a bunch of boats in the Bahamas this past season that had their end-of-life batteries die very quickly once they were regularly at anchor and working off solar alone. You need to proactively change them if it appears its time - before you end up in a place like the bahamas where they charge $300 for a battery.

I can see the appeal of a Honda: Good quality AC power available 24/7 at relatively low up-front cost. My concern is how would I conveniently store it and protect it from corrosion? Build a custom box for it? Presumably it would have to operate on deck, or would there be a way of safely running it inside the engine compartment? I'm sure there are several threads on just that issue.

The Balmar 165 sounds like a good option as it enables you to generate good
charging current when entering and leaving anchorages that would otherwise be "wasted". How many amps does it put out?

Assuming you run your engine, on average, one hour per day when cruising and during that time it puts 100 amp/hrs into a LifePO4 bank (with its high acceptance rate) and assuming your 500 watts of solar and wind generator produce a further 200 amp/hrs your 24 hour total charge would be 300 amp/hrs. Surely this is more than enough for a cruising couple? On those cloudy, windless days you'd have to run the engine a bit longer and/or use a bit less power and/or run down your batteries more.

[Budawang]

Originally Posted by mvweebles

Your water heater may push you over the edge, but otherwise, yes, good setup.

For general budgeting, your solar will generate round 125AH/day. Consumption:
- Microwave takes about 6AH for 5-mins of runtime
- Electric kettle takes around 9AH for 5-mins of runtime
- PCs consume around 2AH per hour of run/charge, so figure 10-15AH/day each
- You didn't mention refrigeration, but that's around 35-40 AH/day
- Ambient lighting - around 10AH/day

All-in, you should be around 100AH energy budget if you're careful; 125-150AH if not. 400AH of battery and 125AH solar will get you dang close to off-grid, if not comfortably so. From there, you can tinker with bigger alternator, regulator, Honda gen, etc.

This really isn't that complicated. Solar, 100A Alternator (FYI - will rarely run more than 50A). It's a good setup for you - my guess is you'll wish you did it long ago.

Peter

That all makes sense Peter, thanks. Not a big deal to for-go the water heater unless it's really windy and sunny and we have excess charge. Or maybe use it just enough to get the water lukewarm to take the edge off our showers.

I hope you're right about wishing I did it long ago

[Budawang]

Originally Posted by Dockhead

You've gotten a lot of good advice, a lot of which is contradictory. Up to you choose what sounds right. There are a lot of different ways to skin this particular cat.



At the risk of not saying anything necessarily new, I would just add:


1. Lithium vs. lead acid really depends on how much you are using the batteries. If you are off grid a lot and cycling the batteries A LOT, then lithium will pay for itself. so not only better, but actually cheaper, as the cost per cycle is less IF you cycle enough to be wearing out lead acid batteries more often than say every 5 years. And lithium is much BETTER, works better, is more efficient, less hassle. So I think it's not at all dumb to be considering this.


2. If you go lithium, don't use the pre-made drop in conversion units. They are costly and the only point is to avoid converting your charge and management infracture. Better bite the bullet and do the conversion, and by raw cells. Lot of information in this forum how to do it.


3. If you go lead acid, then go with golf cart batteries (Troject T105 or whatever). Quite robust, yet cheap.



4. Make sure you have good battery monitoring and management even for lead acid. You especially want a top notch charger (which maybe part of an inverter charger).


5. Do upgrade the alternator whether or not you replace the generator. Just use a plain old school bus alternator, e.g. Leece Neville -- cheap and good. Add external regulator like Balmar. You especially want the external regulator if you choose an alternator big enough that you might bog down the engine at certain RPM's when you're using it for propulsion. The Balmar allows you to dial down the power using a switch at the helm.


6. More solar? There's kind of no such thing as too much solar PROVIDED you have space for it and you are not causing too much windage. Be careful about the second question if you are a keen sailor.


7. Replace generator? You might really not need to with both a heavy duty alternator AND a fair amount of solar. But if you, look at the cheap and good ones from NexGen and Phasor. Or a DC generator.



8. Oh, and don't let inverter efficiency drive a decision to be DC or AC or do without an AC generator. Tail wagging the dog. Inverters are efficient enough.

Thanks Dockhead - lots of good points. You figured out that I'm on a bit of a budget . I'm thinking of going with 2 x Amptron 200 AH as they seem to have good specs (link below) and a good reputation for quality and value at about $1,350 USD equivalent each here in Australia. I know they're not the raw cells you're recommending, but I'm not confident enough in my skills to install those myself and electricians aren't cheap...

https://www.amptron.com.au/uploads/1...n_20181130.pdf

We have a good quality recent Victron 60A lithium compatible charger. I think our wind gen controller can be re-programmed for lithium. I'll investigate the school bus alternator as the Balmars seem expensive.

[mvweebles]

Originally Posted by Budawang

That all makes sense Peter, thanks. Not a big deal to for-go the water heater unless it's really windy and sunny and we have excess charge. Or maybe use it just enough to get the water lukewarm to take the edge off our showers.

I hope you're right about wishing I did it long ago

I once had a generator with a one cylinder yanmar. Probably not unlike your Farrymam. Anything is better..

If your water heater has a heating circuit from your engine, you can plan accordingly for hot showers, etc.

I would get the panels setup and inverter in first and see how it goes.. Relatively inexpensive and biggest bang for buck. From there, will be easier to figure out how many batteries, whether you want/need a Honda, etc. Unless you have problems with shading (do mount a separate MPPT for each panel), my guess is you'll be just fine. Even if you need something more, unlikely you'd regret the solar install.

Peter

[Budawang]

Several people have been making the argument for a Honda portable generator. While it would be great to get all our power via wind and solar, I can see the logic of having a small petrol generator. My question is, would it make sense to get the little 1kw Honda which we would solely use for charging out LifePO4 batteries via our 60A charger? Could we just use our 2000W inverter (powered by the batteries) for all our other household AC needs? In other words, the Honda would be solely dedicated to replenishing our batteries. Does this make any sense or is it better to get the Honda 2kw version?

My reasoning is that the 1kw model should be more than capable of providing maximum power to the 60A charger. It is also a bit more compact with storage space at a premium on our boat.