Genasun & Victron, power to spare?

Ben Ellison

Ben Ellison

Panbo editor, publisher & chief bottlewasher from 4/2005 until 8/2018, and now pleased to have Ben Stein as a very able publisher, webmaster, and editing colleague. Please don't regard him as an "expert"; he's getting quite old and thinks that "fadiddling fumble-putz" is a more accurate description.

26 Responses

  1. David Marchand says:

    The Hutchins has four Victron inverter/chargers? Wow!! Assuming that they each charge at 100 amps, then that is a charging rate of 400 amps if it is a 12V system. Probably ok for a lithium battery, definitely way excessive for lead acid, but that is one of the advantages of a lithium (or to a lesser degree, AGM).
    And those chargers aren’t very efficient and have a lousy power factor. Each can draw about 15 amps of 120V AC at the full charging rate. That is 60 amps!!. Most shore power systems are limited to 50 amps at 120V, more if 220V but that is less common.

  2. Patrick says:

    So what did that battery bank cost I wondered so I followed the links.
    “2x 360Ah, 24V 203kg $27,000.00
    House battery systems are composed of two completely redundant banks, and capacities listed are that of each bank, half the total.”
    I assume you meant 720 in the post not 760. I don’t see a setup on their site for a 2x380Ah setup. Maybe it was custom.
    Anyway, WOW $27K !!!

  3. Bruce Schwab says:

    It was great to work with Alden, Kim, and the Team at Yachting Solutions on the Huckins 45 project! VERY cool boat (and I don’t say that very often for powerboats)
    I haven’t gotten a ride yet tho…what’s up with that?

  4. Russ says:

    The economics of these batteries are getting closer. I calculate it as 2x cost, 25% weight, and about 60% of the engine charge time for equivalent capacity.
    Taking 1,500lbs out of my boat could translate into a shorter rig, smaller sails and other cost savings, though not as a refit. Less engine time is fuel, maintenance and the tedium of listening to the engine run to charge the batteries.
    But the big fly in the ointment is the warranty. Mastervolt Gel cells only claim 1,000 cycles, but come with a 7 year warranty. The Li batteries claim 2,000 – 3,000 cycles, but only come with a 2 year warranty. If the claims are valid, why don’t the Li batteries come with at least a 7 year warranty, if not 15-20yrs?
    Until the warranty supports the claimed life of the batteries, the claims have to be seriously discounted, which means the effective cost is more like 6x, than 2x. Those economics don’t work.

  5. Dan Corcoran (b393capt) says:

    Russ: 1) I suspect the warranty being short has a lot to do with concerns the battery will be mistreated, e.g. exposed to too much moisture or heat, left uncharged for long periods of time, or subject to the abuse of either a charging system failure or abused by being connected to an alternator absent a smart 3 stage regulator. (such issues have made AGM batteries live much short lives, on the order of 2 years)
    2) Russ: What if you could get a battery half this size (380 Ahr), upgrade to a 500 Amp alternator, and could bring the battery from 35% to 95% charge (+60% or 225 Amps) in 30 minutes.
    What if I told you such a small battery could also drive a 3,000 or 5,000 watt inverter with ease (e.g. low power loss) to power a microwave, hair dryer or whatever without so much as dimming the lights (with appropriate battery cabling)!
    Does that fix the economics for you?
    If not, wouldn’t it just be great to charge your battery in 30 minutes at an anchorage, and get back to peaceful quite quickly ?

  6. Russ says:

    1) This list of risks is the same for both Gel and Li batteries, though I had previously believed that the Li batteries did not need a 3 stage charger. If they all share the same risks, why the difference in warranty?
    2) As I said: 25% of the weight and 60% of the charge time. Perhaps I wasn’t clear when I wrote “Less engine time is fuel, maintenance and the tedium of listening to the engine run to charge the batteries.” that I meant to imply there would be less maintenance, less fuel consumption and less time listening to the engine charge the batteries – all a plus for Li.
    3) My existing Gel batteries, 1,000ahr @ 24v, run a 4KW inverter which drives AirCon, microwave, toaster, hair dryer, etc. “without so much as dimming the lights”. No advantage to Li there.
    4) I have 2x 150a @ 24v alternators now and they are quite large. I can’t imagine how large a single 500a @ 24v alternator would be, or where it could be purchased, but I assure you it would put an awfully unbalanced load on the PTO of my Yanmar 110hp main engine!
    The benefits vs Gel are clear: less weight, less volume, faster charge and less engine/fuel cost.
    The costs are also clear: 2x for equivalent capacity.
    The unexplained issue is why the warranty does back up the life cycle claim.

  7. Russ says:

    Correction: The unexplained issue is why the warranty does NOT back up the life cycle claim.

  8. Dan Corcoran (b393capt) says:

    Russ wrote “3) My existing Gel batteries, 1,000ahr @ 24v, run a 4KW inverter which drives AirCon, microwave, toaster, hair dryer, etc. “without so much as dimming the lights”. No advantage to Li there.
    –> Yea, but not with a 380 Ahr sized Gel.
    Russ wrote “4) I have 2x 150a @ 24v alternators now and they are quite large. I can’t imagine how large a single 500a @ 24v alternator would be, or where it could be purchased, but I assure you it would put an awfully unbalanced load on the PTO of my Yanmar 110hp main engine!”
    –> You given me a hard time for some reason Russ! You know I am not talking about one alternator. I had forgotten that your boat, which I admire (you remember I sent you the pic when Perry wrote about it), had 24v. Wow 300A of 24V, geez, you need no more that’s for sure.
    Russ wrote “The benefits vs Gel are clear: less weight, less volume, faster charge and less engine/fuel cost. The costs are also clear: 2x for equivalent capacity.”
    –> Since you didn’t give us the math, tell us simply what the cost would have to be, to be 1x.
    –> Approx what is your energy budget for a day ?
    –> Approx how charged up does your Gel cell get before it won’t take all the power your alternator is putting out, 70%, 75% ?
    –> Approx how much time do you need to charge the batteries each day, what range are you generally charging them from and to ?
    … this is leading somewhere.

  9. Russ says:

    Dan – Thank you for the kind words regarding New Morning, but I’m not trying to give you a hard time. I am however trying to challenge the makers and distributors of the Li batteries. To answer your questions:
    1) 1,000ahr @ 24v of Gel cells at current Mastervolt list prices are about $12,000.
    2-4) I run the batteries from about 90% to 40%. In gross terms I’m using about 500ahrs of capacity. Equivalent Li capacity would be about 2x the 380ahr Li you mention.
    Supplemented with solar and wind, I re-charge with the engine every 5-10 days so that computes to a net consumption of 50-100ahrs / day. The considerable variability is due to wind, sun and consumption.
    When I do charge I run the engine for 3-3.5 hrs, more like 3.5 now that the water is warmer (85+) so the temp compensation pulls down the charge voltage/current.
    While I always enjoying talking about New Morning, my point is about the Li batteries backing up their claims with a warranty. I know from my professional experience, and experience as a consumer, that when products are not backed up by a warranty, there is a reason. I don’t need convincing that I’d much prefer to have the Li batteries, but how to explain away a 2 year warranty on $27K of Li batteries (from Bruce’s web site), versus a 7 year warranty on $12,000 of Gel batteries? Those are the economics that are tough to accept.

  10. Henning says:

    How about the following steps to find out if Li-Ion batteries work economically in a specific situation:
    1. How much charge current is available realistically and economically (a) engine-driven, (b) from shore power
    Wind and solar power, while certainly helpful, can probably be left out of this argument as it will only help to reduce the number of recharges, not the number of amp hours to be charged when charging (based on the assumption that you will start charging when the batteries reach a lower threshold – like Russ).
    2. What is the battery capacity that will accept this charge current at each of the compared battery types (AMG vs. Li-Ion)?
    3. To this capacity, apply the healthy percentage of discharge between charges (AGM may be used between 90% and 50% of charge so 40% of usable capacity; Li-Ion will be much higher percentage but applied to a smaller total capacity). This gives you the number of amp hours between charges. Do this for both battery types compared.
    4. If you are happy with the number for AGM, then Li-Ion will not give you much benefit and will generally not be worth the extra expense. You are then in a shortage of charging capacity (but since you are happy, who cares?). If you are not happy with the value for AGM but happy with Li-Ion, then Li-Ion will benefit you and may be worth an extra expense. If you are not happy with either value, you *must* increase charging capacity.
    Dan and Russ covered the subject of charging capacity but I think it deserves the center spot.
    The 4 Victron Energy inverter/chargers on this boat, besides being a considerable expense, also add bulk and weight that counteract the savings from the Li-Ion batteries. On the above boat, they certainly exist not because 12KW of AC consumers on board must be supported but to provide x number of amps of shore power charging. But is the shore power connection big enough for this? Only 1 out of 25 shore power connections that I know would provide 12KW without tripping the breaker.
    I have a very small 12V DC generator (Fischer Panda AGT) that provides 2,5KW = 130A of charge current and I plan to install a 150A Balmar high output alternator. There is no room (and certainly no budget) for a larger generator. Adding significantly more alternator capacity is also not feasible unless they are mounted off-engine and coupled via a hydraulic power take-off (you cannot add a big weight to the side of you engine without risking damage to the engine mounts). I wouldn’t know where to put this and having it installed is probably near-prohibitively expensive.
    The 130A to 150A of charge current is matched to my almost new 600AH of Victron Energy AGM house bank. It gives me 240AH between charges. This is as good as it’s gonna get on a 10 year old 45ft sailboat and good enough to live on for a while. So Li-Ion is not for me (unless I ever need to replace my main engine).
    In the case of Russ Li-Ion might make sense given 300A at 24V (identical to 600A at 12V) of engine-driven charging. Shore power charging capacity is probably less important when cruising off-grid. If it were, then, again, 4 coupled inverters would take up the space and weight just vacated by the AGM batteries replaced by Li-Ion, meaning that only “reduced charging time” would remain as a benefit of Li-Ion.
    In the case of a newly built good size boat with electical propulsion and a corresponding 48V battery bank with a usable capacity of several thousand AH, the benefits of Li-Ion are probably compelling. In that case, probably 30% of the total build cost of the boat would be for batteries. And I agree with Russ in that I wouldn’t spend this much money on something that may only last 2 years. Toyota requires an average expected life of the battery of close to 10 years and for that reason, as far as I know, on the current production model of the Prius, are still stuck with NiMH batteries.

  11. Ben Ellison Ben Ellison says:

    A clarification: As I understand it, the reason this boat has four Victron Multipluses instead of two is that one pair is assigned exclusively to shore power and the other to the generator, so that no switching is required.
    Also I heard Bruce discuss various Lithium batteries at a boat show last winter, and gather that Genasun are about the most expensive because they have the most protection built in. In the photo you can sort of see circuit boards that monitor and equalize each cell on the right hand battery, whose cover is removed. There’s also a black box associated with each battery that’s not in the photo.
    According to Bruce, a person willing and able to monitor a lithium battery can get one of the less expensive models he represents. But less expensive does not mean inexpensive! I suspect these batteries are only “practical” for very weight sensitive boats at this point. Maybe the Huckins is in this category, or maybe the owner is experimenting. Whatever, it will be interesting to see how it works out.
    Maybe Bruce can comment on the warranty question, which seems like a valid concern?

  12. Charlie J. says:

    Great post Ben! The LFP batteries are penetrating the marine market now.
    I am currently designing an LFP installation on a 49′ sailing cat.
    There are some misconceptions posted in the comments. Let me clarify:
    1. Victron MultiPlus inverter/chargers have a power factor of 1.0.
    2. LFP batteries require a constant voltage charging source. They will tolerate a properly developed three stage charging algorithm but are most efficient with constant voltage.
    3. LFP batteries have a very flat charge/discharge curve between 10% SOC and 90% SOC.
    4. There is no Peukert effect with LFP batteries; i.e., your bank does not shrink in available capacity when you heavily discharge it.
    5. Large alternators can be safely mounted on smallish engines by using available side mounting kits that essentially turn the main crankshaft pulley into a PTO unit.
    6. LFPs used for essential service should have an integrated battery management system (BMS) to ensure charge balance between the cells.
    7. LFPs do not tolerate low voltage events or high voltage events and have to be protected.
    8. The BMS should drive an alarm circuit that will notify the operator before the bank approaches the low voltage knee associated with a 10% SOC so the operator can take corrective action such as reducing the load on the bank or starting a charging source. If there is no operator intervention, and the SOC

  13. Russ says:

    Lots of good clarification on the Li’s there from Charlie. At the risk of hijacking this thread, I would like to take issue with his characterization of the effects of Peukert’s equation.
    Peukert’s equation expresses the change in effecive capacity due to variations in battery chemistry caused by the rate of discharge, not the depth of discharge. The problem is not how much chemical reaction is necessary to deliver the power demanded (i.e., depth of discharge), the problem is how fast you demand the reactions take place (i.e., rate of discharge).
    A battery’s Peukert exponent is based on its rated discharge rate, typically somewhere between 5-20 hrs depending on the marketing focus of the battery manufacturer. For example, New Morning’s 1,000ahr gel cells have a C-10 rating; they are supposed to deliver 100a for 10 hrs before reaching their fully discharged state of 1.8v/cell. Since we don’t want a 10.8v battery (21.6v in my case), we stop before we’ve used 1,000ahrs, but we could still get our 500ahrs in 5 hrs.
    Peukert’s equation tells us that if you drain the battery faster than the rated capacity, you’ll end up with less than the rated capacity. However, the opposite is also true.
    If you drain the battery slower than the rated capacity, you’ll end up with more effective capacity. Oversize your battery a bit so that you draw it down slower than it’s rating and you get a bigger battery. But keep in mind you still need to put that energy back into the battery when you charge, you don’t get something for nothing. None the less, drain it slow enough and you’ll get 150ahrs of capacity from a 100ahr battery. Of course you can only use 40% – 50% of that 150ahrs, but it’s still 50% more than if you drew it down at the rated rate.
    Confused yet? Isn’t chemistry fun! For a more detailed explanation, and a calculator, see:

  14. Charlie J. says:

    Russ-We are almost in violent agreement!
    The point I was trying to make is that Mr. Peukert will reduce your battery’s amp-hr capacity under heavy discharge thus making it appear as a smaller battery. Likewise, Mr. Peukert is the reason you have to replace 10% to 20% more energy to the battery than what you took out. And, you have to perform the charging in a very controlled manner to allow the electro-chemical process to proceed. For example; a high end golf cart battery manufacturer has reduce their charge rate from 0.4C to 0.17C over the years.
    LFPs, without interference from Mr. Peukert, are able to deliver, and be charged, at C and, in fact, that is conservative!

  15. Alden Cole says:

    Please check out the spec sheet. Here: The power factor is 1. It doesn’t get any better than that!
    Only two of the inverter chargers are used at a time; two on shore power( 30 A each) and two when the gen set is running. They are not run together. Part of this system was inherited from a previous set up. One of the beauties of the system is the power assist capability of the Victron inverter/chargers. If the power at a dock is unreliable in voltage or amperage the Victron can seamlessly jump in and supply the necessary umpf to start the air conditioning, for example. One can also dial back the input from shore, say, if one is at a tiny dock with only a 15A or 20 A outlet is available. (They do exist!) The unit can then assist there too without blowing the dockside breaker. I fiddled with this a bit and found it to work well. Again, the LPF batteries are very well suited For this type of service.
    This was a very satisfying installation experience even with the dragging around a lot of 4/0 cabling in cramped spaces.
    Alden Cole

  16. chriggel says:

    did you get a special firmware to adapt the charging characteristics of the Victron Quattros from three stage IUoU to a simpler IU-curve for the LiFePo4 batteries? I fitted a Victron MultiPlus and two 180Ah Lithium batteries to a 52″ Cruiser-Racer and I am not too happy with the existing charging curve – even though they can be programmed in a lot of different ways. Victron told me, they are about to develop a dedicated MultiPlus just for Lithium batteries. Doesn’t help me, as I already have this unit…

  17. Alden Cole says:

    chriggel, Genasun wants the three stage IUoU set at 14.2V. I found this a little too high and backed off to 14.17V. Still tweaking the set up.

  18. Michael Powell says:

    LiPo batteries are relatively new compared to Gel types, so will have still a lot less exposure to our use. I’ve been using LiPo batteries for a couple of years, and although there have been dead cells, and dire warnings about fire risks, the promise is good. If anything they are sweeter to operate than previous generations of battery including NiCad and NiMh.
    As electric car production ramps up, experience with higher capacity batteries will rapidly build, and the techniques will improve to assemble and protect these batteries from user-abuse. Many auto makers are building plant to assemble large capacity batteries near to their car assemble operations.
    Its difficult to comprehend the capacity of battery required for an electric car, but you might easily run all the electrical services in your house on it.
    If you install LiPo batteries early you will benefit from their many advantages, but you will have to educate yourself to their special characteristics, and how to treat them well. You will also have to buy the current crop of batteries which compared to what is coming, will be practically from ‘cottage-industries’.
    Early adopters will have no doubts, but for the rest, stick to the older batteries for a few more years.

  19. Oceanplanet says:

    Great comments on this thread!! Sorry to have been slow in responding to questions…rather swamped with LiFePO4 battery inquiries (a good thing).
    Regarding the warranty time period for Genasun, that is likely to increase significantly soon. They are currently discussing what is a practical period. One possibility is to also add an extended warranty for a small cost, just like you might do with a new computer.
    Henning and others bring up an important issue with adding significant additional alternator capacity to auxillary engines. This is coming up often with the LiFePO4 installations that I’ve been involved with. So I will soon be offering a special off-engine dual alternator mount driven by a flexible aqua-drive from the crank flywheel. This way, only torsional loads will be on the flywheel rather than side loads. Of course space will be an issue on most boat however it will be as small as possible. Various foot-mount alternators will fit the mount, though the initial design is for two very lightweight 165A x 28V alternators we have sourced.
    The goal of course is 300+ amps DC charging at 28V for Lithium systems (or really huge lead/gel/agm banks)
    Another advantage of lithium that is becoming apparent is for applications using big electric motors (canting keels, electric/hybrid propulsion, etc.). Because of the characteristic of less voltage drop under load (compared to lead), the effective capacity range for operating the electric motors at high output is longer. And faster…we have seen that in canting keel motors the canting time is reduced even with a lithium bank of smaller total capacity than the lead one it replaced.

  20. Oceanplanet says:

    Oops, forgot to address another point posted here regarding the BMS.
    Although a low voltage or high voltage alarm is a nice thing, it is very important the the BMS have the capability to isolate the batteries from either loads or charging sources if something goes awry. What if you aren’t there to hear the low voltage alarm? Or if your shore power or alternator regulation goes bad and drives the voltage too high?
    The Genasun BMS controls relays to TWO positive busses, one for charging, one for loads, so that either buss can still be connected when the other is cut. For instance, if you left the lights on when you fly back home from Tahiti, the BMS will cut the load relay if the voltage goes too low. The charging relay will remain on (to a certain lower voltage point) to allow a charging source (perhaps your solar panels, or whatever) to bring the batteries back up.
    Most importantly…if NO charging source eventually comes on, when the BMS finally cuts the charging relay, it actually turns ITSELF off also. This way there is NO LOAD on the batteries whatsoever. If you are gone for a long time you won’t return to a very expensive mistake.
    Also, the Genasun BMS has a built-in switch for the alternator field current circuit. If you have an overcharge situation the BMS will open the field current circuit first, before cutting the charging relay. Otherwise, you could fry your alternator recitfier diodes if the connection to the battery (load) was cut while the alternator was still charging.

  21. chriggel says:

    good comment on the Battery Management System (BMS). The Lifebatt people require this load shedding circuit and have built-in electronics in their batteries which records any abuse you might do to them.
    On our boat (a 52-foot racer/cruiser) the original installation was absolutely useless: The BMS was hooked up to two huge contactor relays (500A each!). Both contactors were normally activ – even when the battery mainswitch was off. I measured 1.8A running all the time with the mainswitch open…
    So we threw it all out and I used a remotely controlled main switch from BEP to cut the load from the batteries in case of low voltage. This unit just takes 12mA constantly instead of several amps.
    I took apart the housing of the BMS and found that the outputs were already switched by relais – big enough to switch off the Balmar Max charge regulator in case of high voltage alarm directly. The only thing I am still looking for is an “emergency off” input for the Victron Multi Plus Compact Charger.
    The Victron had to be in “battery safe mode” to avoid overcharging. Without this it runs with full power until 14.6V and overshoots a little.
    This is what I like especially: You can quickcharge those LIFEPO4 Batteries – they take the full current until they are 100% charged. A huge alternator makes finally sense.
    Cheers C.

  22. Oceanplanet says:

    Hey Chriggel,
    Are you using Victron’s VE Configure 2 for programing the Multiplus? That should allow you to set the voltage level as needed and put the “bulk/absorbtion” period out to as long as you like.
    That’s what Alden is using on the Victrons on Northern Spy.

  23. bstrong says:

    A little off message but Lithium polymer [Li-poly, Li-Pol, LiPo, LIP, PLI, LiP] batteries are about to become mainstream. Hyundai is shaking up the hybrid automobile market with the Sonata Hybrid model which will use LiPo batteries to outclass the existing sedan hybrids. This vehicle drives beautifully, outperforms the exisitng offerings and underprices them to boot. Think 37/39 [maybe 40] urban/hiway ratings in a very comfortable vehicle for 4 with all the desireable features. Add to that a $3K+ us federal tax credit on a car that reportedly will list for under $25k when available this fall. Sweet. Brian

  24. Oceanplanet says:

    Lithium will change the world! Ha…well maybe. Hard to get excited about all these new “super-efficient” hybrid cars, when my both my 87 and 91 Honda CRX-HFs get 50+ mpg. 55mpg if I cheat a little.

  25. Oceanplanet says:

    Hey Patrick,
    FYI, that $27k is the retail for a 720Ah x 24V system…however the system on board Northern Spy is 720A x 12V…for which the retail price is “only” $14k. Yes, that’s still a lot, but only about 1/2 of what put you into shock…;-)

  26. Jim Flammer says:

    Is this the same Alden Cole from the Sch. Hindu and mate on the Sch. Roseway??

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