Carver Owners Forum

Darn, that is a whole lot of work and money. I hope it works well and suits your cruising needs.
I believe I could run my genny 24/7 for 5 or more years for less $.

I believe I could run my genny 24/7 for 5 or more years for less $.

Not me. 24/7 for 5 years comes to 43,800 hours. Assuming 20-30% load, which wouldn't be great for the generator, mine would consume 0.3gal/hrs of diesel, for a total of 13,140 gals of diesel. At $4/gal average, that comes to just over $50,000!!

Add in oil changes twice a month or more, new alternators, raw water filter cleanings, new belts, fuel filters, etc. Not to mention the fact that I've never seen a generator with 40,000+ hours on it!!

I know you were probably just kidding, but these generators aren't cheap to run and I am definitely fascinated and interested in the overall results of this mod.

So, if I remember from the beginning, your generator was working or at least serviceable. You’ve just had bad experiences with them and wanted a “latest tech” solution. What did you do with it after removal? Same for the chargers. I’m betting many folks out there could use some of those parts and pieces (me included) to keep from spending major $$ on total refits. Maybe help you recoup some of that $$ ?

Got back to our home slip last night. One shore power ran the entire boat overnight and charged what little depletion there was between engine shut down and hooking up. I didn't rush to hook up shore power like I used to because the admiral wasn't sitting in a quickly heating boat, so it was a good 30-45 minutes between engine shut down and shore power hook up.

Looking at the power logs from the trip, at one point after we got underway from Green Cove Springs the alternators were providing 14.2KW to run the boat and charge the batteries back up. This charged the batteries from 66.7% SOC to 98.2% in one hour. After the batteries are charged the alternators only have to provide about 1.8KW each (3.6KW total) to run the boat. The new air conditioners would have made it possible to downsize a generator to 5KW instead of the 7.3KW that was originally on the boat, if I had gone the generator route.

Carverlvr2 wrote:QR_BBPOST So, if I remember from the beginning, your generator was working or at least serviceable. You’ve just had bad experiences with them and wanted a “latest tech” solution. What did you do with it after removal? Same for the chargers. I’m betting many folks out there could use some of those parts and pieces (me included) to keep from spending major $$ on total refits. Maybe help you recoup some of that $$ ?

Thank you, I appreciate the offer to help recoup some of that $$. The generator was sold, or more like traded in, on the overall upgrade. I'm sure I could have gotten more for it if I got it working first. I didn't think about the chargers. I wasn't thinking there was any demand for 20+ year old battery chargers that don't have modern chemistry settings.

tomschauer wrote:QR_BBPOST Darn, that is a whole lot of work and money. I hope it works well and suits your cruising needs.
I believe I could run my genny 24/7 for 5 or more years for less $.

I'm cursed in thinking that very little in boating is done with an ROI, so I probably don't consider cost enough when weighing options. If I did, I would still be rowing my little aluminum boat that I started with in Wisconsin. Heck, we went through about $700+ in gasoline between Jacksonville and Sanford. I do wish I had diesels!

KyleR wrote:QR_BBPOST generators aren't cheap to run and I am definitely fascinated and interested in the overall results of this mod.

We're cleaning the boat up today so I can get some final pictures. Then I'll post a final wrap up with my early thoughts on benefits, pros/cons compared to generator life, and ideas for others who might be considering a similar upgrade.

This is a long post with our final thoughts. We'll try to break it up for easier reading/skimming. The switches between "we" and "I" are somewhat intentional, denoting where it is a shared thought or just the captain's.

The goals of the project and results:
1. Run all house loads while underway using the engines. I already need to have two powerful engines running so why have to also have the generator running?
On this goal the system is a huge success. Not only can we run all loads while underway, the alternators are capable of putting out double the power of the 7.3KW generator they replaced. While it is difficult to determine, I think the gas usage is the same or maybe even slightly better than running a separate generator. To be fair, that might just be my wishful thinking though.

2. Be able to remain comfortable overnight during August in Florida without running any engines.
It isn't August yet, but we did have nights in the high 80F range. At a normal air conditioning temperature setting of low to mid 70F, overnight is more than doable. At our slightly ridiculous high 60F settings, we can still get about 8-10 hours without running any engines.

3. Retain or improve on existing redundancies.
Here the system is another huge success. We've already tested two of the redundancies directly, and a third indirectly. Those include 12v buffer bank charging redundancy using battery charger since the ACR is not switching over for some reason (direct test), compensating for poor shore power (direct test), and generating sufficient power from a single engine/alternator (indirect, but we did record over 7KW output from each alternator). We also have engine start parallel switches now for either house-port, house-starboard, or all three together.

4. A phased approach that doesn't result in any wasted new components, provides as much benefit as early as possible, and minimizes upfront costs.
Yeah... well... 3 out of 4 ain't bad.

Benefits
The biggest benefit is having plenty of silent electrical power available based on our usage profile of predominantly day cruising with nights in a marina. With even a minimum amount of conservation, more than a day of battery only power is possible. If we anchored, then we can run an engine to charge the batteries in an hour or two while we do other high demand activities such as cooking. With more extreme conservation I think we could last 3+ days at anchor between engine runs. This benefit also opens up more creative places to spend the night where running a generator would be restricted.

A lesser benefit is not having a third engine to maintain. This is not a cost benefit, as generator maintenance is certainly cheaper than building a system like ours. However, when considering the cost of installing a new generator this system is only about 50% more expensive based on our original estimates. We hit a lot of other issues unrelated to the system installation, so I can't give a good number on the final cost without all of the remediation we had to do.

Pros/Cons
In addition to the benefits/pros listed above, some other pros we are enjoying include:

• Remote monitoring of the boat, including the electrical system, through Victron Remote Monitoring.
• Our installer can also review logs and make updates without having to visit the boat.
• The Arco Zeus app allows precise, real-time information on the alternator states and engine RPM. I found myself using the app as much as the helm gauges when we were underway.
• Theoretically we can save on marina fees since we only need one 30A shore power instead of two.
• Both gas tanks can be used for generating electrical power, so we essentially double the available gas in an event where we are using the engines only as generators. Assuming a two hour charging run in generator mode every day, we could live "off grid" for about a month with a 20% reserve.
• Switching between power modes is automatic and instantaneous. Victron has done a great job with the Multiplus. As long as we stay below 5KW consumption we can use a single shore power, one or both of the engine alternators, or the house battery bank with no interruption. The departure checklist has been greatly simplified since we basically start the engines, shut off shore power, and go.

Of course, there are also some cons:

• Up front cost. This is certainly more expensive than installing a new generator, and quite a bit more than refurbishing. We probably could have saved a little bit with some different component choices, but it would have amounted to less than 10% of the overall budget.
• The power box weighs more than the generator it replaced, so there is a very slight port list. I used a level and it was essentially undetectable, but the wide swim platform looks just a bit lower on port than starboard. This can likely be compensated by moving some storage around, or even just having two people sit on the starboard side.
• We gave up a lot of storage under the cockpit. Not only is the power box bigger than the generator, we also have the Zeus alternator regulators and some breakers mounted on the water tank enclosure.
• Increased wear on main engines IF they are being used solely as generators. In our case we would typically be running the mains anyway, so this con is very small for our usage.

Should you consider a system like this, and would we do this again?
I've thought about this one a lot over the past few months. Until we were underway on the way home I was still on the fence. The night in Green Cove Springs was all I needed to realize this is something special. Instead of a ruined, very hot night with no dinner, we were able to run air conditioners, make dinner, play video games, and be online. We would not have been able to run the generator where we stopped for the night, and there are other places along the St. Johns River that are similar. I would absolutely do this again, though I really hope I never have to. The admiral seems to be on board too.

But what about others? There is a narrow but growing segment where I think this type of system makes sense. If the boat's layout supports a generator in addition to this kind of battery system, then my recommendation is to keep the generator and add as much battery capacity as possible. This will provide all of the benefits I listed with a less controversial end result. Less controversy leads to better outcomes when the time comes to sell, especially if selling is likely to come in less than ten years. Hopefully in ten years these kinds of alternative power generation systems will be mainstream, and possibly even in demand.

If you aren't worried about controversy, cruise at least an hour or two per day when away from shore power, and are willing to somewhat manage power demands to stay below inverter output (5KW in our case), ditching the generator is a very compelling option.

Picture time!

That's a huge project! Don't suppose you'd share your system diagram with us

vineyardgray wrote:QR_BBPOST That's a huge project! Don't suppose you'd share your system diagram with us

I don't have the final, as built diagram yet. I can give an idea of the components and connections. These connections may not all be correct. I'm going by one of the original system designs that was used for estimating. There are a LOT of breakers, fuses, and shunts involved that I didn't capture here.

120v System Power Sources:

• Shorepower 1 > Galvanic Isolator (existing), RCD > Multiplus II 48/5000/70-95 120V

48v System Power Sources:

• Port 9KW Alternator > Port Ext. regulator > Lynx BMS > 4x 24v 200Ah Lithium NG batteries wired 2S2P
• Stbd 9KW Alternator > Stbd Ext. regulator > Lynx BMS > 4x 24v 200Ah Lithium NG batteries wired 2S2P
• 4x 24v 200Ah Lithium NG batteries wired 2S2P > Lynx BMS > Multiplus II 48/5000/70-95 120V

There is one BMS and one 48v 400Ah bank. This gives about 20KWh of power storage. Both regulators tie into it. The BMS is essentially the brain of everything. The Multiplus is in external control.

120v Power Distribution:

• Multiplus II 48/5000/70-95 120V > Salon Shorepower 1 panel, Automatic Transfer (existing) > Salon Shorepower 2 panel
• Shorepower 2 > Galvanic Isolator (existing), RCD > Automatic Transfer (existing) > Salon Shorepower 2 panel (air conditioning)

Normally we use shorepower 1 by itself which typically runs all house loads, including air conditioning, with left over power going to charge batteries. If needed, we can plug in shorepower 2, which repurposes the generator automatic transfer switch, to power the air conditioning. This allows faster battery charging, the ability to run air conditioning on low quality shorepower, and/or more power available on shorepower 1 for high demand periods like cooking.

12v System Power Sources:

• 4x 24v 200Ah Lithium NG batteries wired 2S2P > Lynx BMS > Battery Protect BP48 > Orion Tr 48/12-30 > ACR
• Multiplus II 48/5000/70-95 120V > Salon Shorepower 1 panel > Phoenix Smart Charger

The Phoenix Smart Charger is supposed to be for backup purposes, but so far we have been having some trouble with the ACRs. The existing port start, starboard start, and deep cycle AGM "buffer bank" batteries were kept.

Monitoring:

• Cerbo GX Mk II > GX Touch 70 (48v system)
• Cerbo GX Mk II > GX Touch 70 (12v system and tanks)
• Orbi Mesh Wifi > Verizon 5G Internet > Victron Remote Monitoring
• Arco Zeus App (bluetooth-onboard only)
• NMEA2000 (Garmin 5212 is not interpreting the PGNs, so limited use)

Normally we use shorepower 1 by itself which typically runs all house loads, including air conditioning, with left over power going to charge batteries. If needed, we can plug in shorepower 2, which repurposes the generator automatic transfer switch, to power the air conditioning. This allows faster battery charging, the ability to run air conditioning on low quality shorepower, and/or more power available on shorepower 1 for high demand periods like cooking.

I'm trying to wrap my brain around how you have the multiplus connected to the panel - especially how you are running Aircon off of Shore Power 1. Like you, I have two mains circuits from the shore, Shore 1 runs all house loads except air and Shore 2 only air. But I have no means to combine Shore 2 with Shore 1 in order to run air from a single Shore power cable. Even if I did, this would most certainly overload the pedestal breaker (although I assume in your case you'd be using the "power boost" functionality of the multiplus to get around that?)

I have switches on each oncoming branch that read Shore Power, Ships Power, Generator and Off - assume you left the existing shore wiring intact to the panel and wired the multiplus up to the Generator input (and are not using the Automatic Transfer Switching ability of the multiplus)?

Grid Shore 1 comes in to the multiplus. The multiplus goes out to both shore 1 and shore 2 at the panel with shore 2 via the original automatic transfer switch that used to be used for the generator. If we have grid shore 2 connected, the transfer switch transfers shore 2 at the panel (air conditioning loads) to the grid and the multiplus only powers shore 1 at the panel (other house loads).

As I type this we are on grid shore 1 at 1,974W (121v @ 16.3A), through the multiplus powering both shore 1 and 2 at the panel, and using 1,725W for the entire boat. We have both air conditioners running at about 70F, XBox, TV, soundbar, and some plug in lights on. The remaining 249W is going to the batteries and DC loads. My second shore power cord is stowed, where it has been since we pulled in to the marina last week. We have the grid amperage limit set at 24A, so if we need more than that the assist mode kicks in to draw the extra power off the batteries. This happens when we are cooking or turn on the water heater. Once those loads are off we go back down to the 1,700W to 2,000W range and can run off the single cord with some excess to charge the batteries back up.

We're in the middle of a thunderstorm that took the power out at the dock for a few minutes about a half hour ago. The plug in light flickered, but that was the only indication we had that we lost shore power. When power came back on a few minutes later, the multiplus ramped up the draw from the grid over a few minutes to the 1,974W I reported above.

I was able to get some pics inside the "magic box" today. Unfortunately I was able to get those pictures because we had to have the BMS replaced due to a lightning strike at our marina. We are in a covered slip and about five or six boats under cover had some electrical damage. Thankfully I didn't have to try to get the boat back to St. Augustine. There are quite a few issues from the lightning, but that is another post for another day.