New Generator or Lithium?

[Pete7]

No room on 43 feet? We would probably install a telephone exchange if we had that much space

I would start by reading these articles by Mainesail, a member of the forum.

https://marinehowto.com/category/alternators/

[valhalla360]

If your current system is serving you well and you only run the generator 30min a day...probably fine if you intend the same usage pattern.

Heating (water or cabin) is a challenge with battery.

Take that out of the mix and you could probably scale down the lithium bank:
- Lead Acid doesn't like to go below 50% and it's hard to get it much above 80%, so you really only have around 1/3 of the current 330amp-hr rating (ignoring that they are old and probably can't produce the rated amp-hr). So even if you assume you do a full charge, you probably only have around 150amp-hr of usable power.
- Lithium is happier over a much wider range and will continue to accept bulk charging until pretty much 100%. Let's say we are conservative and assume you cycle them from 20% to 90%. That's 70% of the rating as usable power, so 400amp-hr bank would have 270amp-hr of usable power (some people suggest 10% to 100%)... You could probably cut the bank down to something on the order of 250-300amp-hr and have it perform better than the current bank.

Also when you say you cruise part time...what is that like? A long weekend, you can let the solar have the batteries topped up for when you arrive Friday night. If you stick with a 400amp-hr bank, you can probably get two days without running the alternator...then put her back in her slip for the week only to return fully charged the next weekend. When you do cruise for a week or so, you can run the motor every 2nd or 3rd day but since it's only occasionally, not a big deal in terms of wear and tear on the engine or fuel consumption.

[Augi]

Originally Posted by Budawang

You've convinced me I should look at upgrading my alternator, regardless of whether I install LifePO4, AGMs or lead acids. Can you recommend a brand/model that would do the job?

Depending on how much electrical power you need and how much you want to spend you could go to system as described at the link below by Nigel Calder. Minimum size engine for the system shown at the link below is a 40 HP propulsion engine. The system described will generate approx 4-5KW at a high idle of your propulsion engine and 8-9KW running at peak RPM of your propulsion engine. Apparently the above system is more efficient to charge batteries than running a 5KW standalone generator.

https://www.youtube.com/watch?v=0uTN...ature=youtu.be

Whether lithium batteries are the right call with the above system(or any systems for that matter), depends on how long you plan to have the system(lithium are usually cheaper over the long haul but cost a lot more upfront), how much electrical capacity you need, and how often and for how long you want to run your propulsion engine to charge the batteries.

The system described at the link above costs $12K not counting batteries.

You can learn more about the system at the links below.

https://integrelsolutions.com

https://www.youtube.com/watch?v=5hHf8qII1Bg

As already discussed on the thread other options you can go with an alternator with greater output or use a Honda portable generator(but a portable generator has safety issues) or go with a phasor or next gen marine generator or similar 3.5KW-5KW marine generator(to replace what you have), that will cost about about $10K-$12K inlcuding installation.

If what Nigel Calder is saying in the first link is true your $12K will be better spent on the system presented do to the efficiency gains.

Nidel Calder appears to have a financial interest in the success of the system presented. I would trust Nigel Calder as much as anyone in the marine industry making similar claims. But as Ronald Reagan once said, "Trust but verify". In other words get a demonstration or wait for an independent sound test of the system.

As other posts have pointed out keep clear between what generates power or stores power. Diesel and batteries store power. Alternators, generators make power, solar panels, hydro generators and wind generators.

[joelhemington]

Originally Posted by Budawang

Thanks for the advice. I will see if we can add a bit more solar. I think you're also implying that inverters are quite inefficient. We would only use the inverter for charging two laptops and light use of microwave and galley appliances. Won't need to run watermaker unless we are motoring. Energy use will be higher when we are sailing long distances, but we are not big energy consumers. Does the following average daily power budget for the East Coast of Australia (quite sunny and windy) look realistic?

Solar 400 watts: 120 AH
Rutland 1200 wind generator: 50 AH
Engine 30 min/day 100 amp alternator: 50 AH

Total: 220 AH.

Perhaps with this energy budget it would make more sense to have 300 AH of battery storage? It doesn't make sense having a mismatch between generation and storage capacity.

A couple of things: One, most of your engine time should be in and out of marinas - not a good place to be making water. Two, upgrading your existing solar array would make a lot of sense. If space is your issue, then get higher performance panels (they're all about the same size) And don't forget the 3-4-5 rule. For high quality panels like Sunpower divide your total watts by three to get your expected daily AH rating. For lower end panels, divide by 4 and for the cheapest polycrystaline panels divide by 5. You get what you pay for.

[blinkerfluid]

We are in the middle of a pretty big refit on our 42' boat and had the same decision to make. When we bought the boat, the generator was shot, so we needed to decided between new generator or lithium. We ended up going with 600ah of Lithium, but part of that change also included adding an arch and 1125 watts of solar. We have no wind generator at the moment, so will primarily rely on solar for charging. We went with a full Victron system that we installed ourselves, which included new batteries, BMS, battery protects (disconnects controlled by BMS), inverter, and solar charge controllers. We also added a Balmar 170 amp alternator with external regulator (and temp sensor to protect the alternator) as our backup means of charging the batteries.

Unfortunately, the system is still new to us and the boat is on the hard; so other than general testing of the system, I can't really report how it's working in the real world.

Here's a picture of what our house bank looks like:

[a64pilot]

Originally Posted by blinkerfluid

We are in the middle of a pretty big refit on our 42' boat and had the same decision to make. When we bought the boat, the generator was shot, so we needed to decided between new generator or lithium. We ended up going with 600ah of Lithium, but part of that change also included adding an arch and 1125 watts of solar. We have no wind generator at the moment, so will primarily rely on solar for charging. We went with a full Victron system that we installed ourselves, which included new batteries, BMS, battery protects (disconnects controlled by BMS), inverter, and solar charge controllers. We also added a Balmar 170 amp alternator with external regulator (and temp sensor to protect the alternator) as our backup means of charging the batteries.

Unfortunately, the system is still new to us and the boat is on the hard; so other than general testing of the system, I can't really report how it's working in the real world.

Here's a picture of what our house bank looks like:

What was the cost?
This guy, and most of us are on a budget.
Budget wise, you cannot beat a Honda and golf cart batteries, nothing will get you close to that kind of power for so little money (US costs) I don’t know about other parts of the world.
Golf cart batteries are $1 an AH, Firefly about $5 an AH.

Of you have a Yanmar the engine manufacturers max limit on the power you can pull off the front of the crankshaft is about 100 amps at 12VDC (4 HP) exceed that and your exceeding the manufacturers limit, will it last? Maybe but I stay within limits myself.

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.

[Budawang]

Originally Posted by valhalla360

If your current system is serving you well and you only run the generator 30min a day...probably fine if you intend the same usage pattern.

Heating (water or cabin) is a challenge with battery.

Take that out of the mix and you could probably scale down the lithium bank:
- Lead Acid doesn't like to go below 50% and it's hard to get it much above 80%, so you really only have around 1/3 of the current 330amp-hr rating (ignoring that they are old and probably can't produce the rated amp-hr). So even if you assume you do a full charge, you probably only have around 150amp-hr of usable power.
- Lithium is happier over a much wider range and will continue to accept bulk charging until pretty much 100%. Let's say we are conservative and assume you cycle them from 20% to 90%. That's 70% of the rating as usable power, so 400amp-hr bank would have 270amp-hr of usable power (some people suggest 10% to 100%)... You could probably cut the bank down to something on the order of 250-300amp-hr and have it perform better than the current bank.

Also when you say you cruise part time...what is that like? A long weekend, you can let the solar have the batteries topped up for when you arrive Friday night. If you stick with a 400amp-hr bank, you can probably get two days without running the alternator...then put her back in her slip for the week only to return fully charged the next weekend. When you do cruise for a week or so, you can run the motor every 2nd or 3rd day but since it's only occasionally, not a big deal in terms of wear and tear on the engine or fuel consumption.

First, I'd like to say I'm blown away by the quality of advice on this thread.

Valhalla: We cruise weekends but also longer periods up to six months at a time. Our yacht is on a mooring and not a slip, so we can only connect to mains power every couple of weeks when we visit a marina.

Yes, I think we would be ok with 300 amp/hr of LifePO4s. I'm leaning towards 2x160 amp/hr Victrons. I guess we could always add another 160 amp/hr Victron later if we want more storage. Enerdrive LifePO4s also look good and are about 20% cheaper here in Australia.

[blinkerfluid]

Originally Posted by a64pilot

What was the cost?
This guy, and most of us are on a budget.
Budget wise, you cannot beat a Honda and golf cart batteries, nothing will get you close to that kind of power for so little money (US costs) I don’t know about other parts of the world.
Golf cart batteries are $1 an AH, Firefly about $5 an AH.

Of you have a Yanmar the engine manufacturers max limit on the power you can pull off the front of the crankshaft is about 100 amps at 12VDC (4 HP) exceed that and your exceeding the manufacturers limit, will it last? Maybe but I stay within limits myself.

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.

No doubt Lithiums are expensive, but my entire system was still cheaper than a new generator.. and significantly less expensive than the $12k + batteries mentioned in a link above. If you want to compare dollars per amp hour though, it's really only fair to compare cumulative amp-hrs for the projected life of the system.

Our boat had six 6v golf cart batteries when we got her. Those batteries were rated at 210 ahr each with a 500 cycle life expectancy at 50% discharge.. that would be about 158k ahrs over the life of the system. Trojan t-105s are about $190 ea (Based on a quick google search).. so figure about $7.20 per 1000 ahr.

We have 600 ahrs with a 2500 cycle life expectancy at 80% discharge.. that would be 1,200,000 cumulative ahrs over the life of the system. For our batteries, that works out to about $4.60 per 1000 ahrs. In the long run, our batteries could possibly work out to be cheaper than lead acid, and we won't have had to lug 600+ lbs of batteries off the boat 5x. We didn't go with Lithium on any perceived future savings though, we bought them because of all the other benefits they have (weight, size, charge/discharge efficiency, no voltage sag, no penalty for fast discharges, etc.)

Everyone has a budget to live by, including us. The battery setup is one of our big splurges. We saved money in other places.


To Budawang: If you're thinking of getting Victron 160's, I'd definitely suggest looking at their 200's instead. They're exactly the same size as the 160 (a few pounds heavier) and only a little more expensive.

[Budawang]

Originally Posted by blinkerfluid

To Budawang: If you're thinking of getting Victron 160's, I'd definitely suggest looking at their 200's instead. They're exactly the same size as the 160 (a few pounds heavier) and only a little more expensive.

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?

[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.

[downunder]

Budwang,

not sure where you are based but there are a number of Australian manufacturers some of them using prismatic cells to build their drop in replacement cells with internal BMS Most have 200ah batteries

Amptron in WA https://www.amptron.com.au/about.html

Lithium Battery Systems in Brisbane
https://www.lithiumbatterysystems.co.../user-stories/

Enerdrive based in Brisbane https://enerdrive.com.au/contact/

Also EV systems in WA https://www.ev-power.com.au

[chowdan]

For me personally I stuck with Firefly and a balmar alternator with solar. I have a single 350w LG panel and will be adding a second one in the coming months.

Lithium sounds great on paper, but I do not trust the BMS system. For a cruising boat, I look to make systems as simple as possible with the least amount of potential failures. If the BMS fails, your battery goes down(regardless of cell failure or not).

With AGM/FLA, you have to have a cell failure to bring down a battery, nothing else.

[Budawang]

Originally Posted by downunder

Budwang,

not sure where you are based but there are a number of Australian manufacturers some of them using prismatic cells to build their drop in replacement cells with internal BMS Most have 200ah batteries

Amptron in WA https://www.amptron.com.au/about.html

Lithium Battery Systems in Brisbane
https://www.lithiumbatterysystems.co.../user-stories/

Enerdrive based in Brisbane https://enerdrive.com.au/contact/

Also EV systems in WA https://www.ev-power.com.au

It's good there's still some manufacturing left in Australia. The Amptron's sound like very good value compared to Victron. To some extent you get what you pay for I guess.

[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 😊

[downunder]

Originally Posted by Budawang

It's good there's still some manufacturing left in Australia. The Amptron's sound like very good value compared to Victron. To some extent you get what you pay for I guess.

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

https://www.youtube.com/watch?v=G5E30u-66VI&t=7s

https://www.youtube.com/watch?v=aahHWaV6Zdk

https://www.youtube.com/watch?v=8UJYm4g1z1s

https://www.youtube.com/watch?v=6hgs2jQoEcI