Lithium Ion Batteries

Ebaugh said:

It's hard to compare I think? The answer here is solar and wind, most every sailboat has one or the other and quite a few have both. I would add solar the next time around if at all possible.

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Good stuff Ebaugh. It is nice to see someone really using their boat. Do you have Prestolite alternators? What do you guess is the relative cost of a wind generator vs solar panels?

Where are the 500 ah going? You mention a plethora if refrigerators. Is this the biggest drain on your system?

I'm assuming you have a 12v battery? Charging from a 110 charger using generator power? Perhaps a variable speed DC generator would add to efficiency?

Small wind can produce power whenever wind speed is higher than the cut in speed of the turbine, day and night. Along the east coast of the U.S. a turbine rated at 1.5kw will average about 350 watts 24/7. It does add up - just don't expect 1.5 kW 24/7. Likewise solar. Not really either or - do both!

If you're using 6,000 watt hours/day a 4 kW DC generator should replenish in 2 hours. If you're using a 100 amp charger (typical of charger inverters), no wonder it takes 5 hours to replenish the 500 amps you've used. You can "hammer" a LI battery! If a DC gender is not in your future, perhaps a high capacity 3kw or bigger 120/240 v charger is?

sunchaser said:

Good stuff Ebaugh. It is nice to see someone really using their boat. Do you have Prestolite alternators? What do you guess is the relative cost of a wind generator vs solar panels?

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We converted both engines to Leese Neville Prestolite alternators model:

http://www.prestolite.com/pgs_produ...tail_id=897&item=8MR2070TA&product=Alternator

This was well before the battery project. For about $200 each, we've been very satisfied. It's about all you can get away with on a single standard belt for a pretty simple retrofit. The adjustable regulator is a good feature.

A basic wind generator or basic solar system are probably in the same range 2-3 boat units ($1000) including mounting modifications. Plus labor if you don't DIY. The only advantage of wind is it works better on cloudy windy days. Otherwise, solar is silent, vibration free, less prone to failure and more easily extendable to higher output levels. You might guess I like solar.

You can expect either on "good" days to carry basic lighting and one small marine refrigeration system. Not the full size refrigerators seen on some trawlers.

No way we could carry our full requirements with the footprint for panels I have available, but we could maybe cut it in half. However to really see big benefits, we also need to change the galley to propane. I'm a little reluctant to do that since getting the tanks refilled is an extra hassle compounded since not every place uses the same fittings. But there are probably fewer electric galleys than trawlers here in the Carib, so I'm a bit out in left field. I have seen only 1 sailboat the whole trip with an electric galley. Offhand, it's probably a 5 year payback for us to add solar and convert the galley. And only then if we expect to continue with our same profile. Unfortunately, we expect to be back to work late this year and are not sure how long till we are able to slip the lines from a marina and get back cruising.

rjtrane said:

Where are the 500 ah going? You mention a plethora if refrigerators. Is this the biggest drain on your system?

I'm assuming you have a 12v battery? Charging from a 110 charger using generator power? Perhaps a variable speed DC generator would add to efficiency?

Small wind can produce power whenever wind speed is higher than the cut in speed of the turbine, day and night. Along the east coast of the U.S. a turbine rated at 1.5kw will average about 350 watts 24/7. It does add up - just don't expect 1.5 kW 24/7. Likewise solar. Not really either or - do both!

If you're using 6,000 watt hours/day a 4 kW DC generator should replenish in 2 hours. If you're using a 100 amp charger (typical of charger inverters), no wonder it takes 5 hours to replenish the 500 amps you've used. You can "hammer" a LI battery! If a DC gender is not in your future, perhaps a high capacity 3kw or bigger 120/240 v charger is?

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Yes it's 2 under counter home style refrigerator only units, 1 ice maker and 1 small chest freezer all 120VAC. Plus averaged out, probably 50Ah daily for the DC water maker. Finally, I'm not exactly sure the use, but we have a couple of computers used frequently and a couple of network devices powered all the time. Lighting is almost all LED including the anchor light. Except the engine room where those lights are all fluorescent and take about 10A when I am working in there. But I still figure the refrigeration at 80% of the total usage.

We have 1200 Ah at 12V of LiFePO4, primarily recharged from 2 inverter chargers capable of charging 100A each for 200A total. Also have 2 generators, one 11 KW (old) and one 9 KW (new), although they are almost at matching hours now. If I had it to do over I would get the 12KW instead of the 9. Other than size and diesel engine loading requirements, I'm not sure there is much difference in fuel consumed for lighter loads on a bigger generator. When we start the generator, we pretty much pull 45A right away for the water heater, and both battery chargers. Add only 2 of 4 stove elements and we are at 65 of the 75A maximum output of the 9KW. If I dial one of the chargers back to 50A, we can usually get 3 stove elements or 2 plus the microwave. But forget about A/C, nothing left for that until the water heater is off.

The morning cycle usually includes not only "brunch", but some baking or cooking dog food etc. The dinner cycle usually takes longer to prepare. This drives at least 3 hours generator time on a typical day. Enough at 150A to almost cover usage on non water maker days. But that is lower than what I reported in my earlier post, something I need to get my arms around now that I have the figure.

The refrigeration system is not terribly efficient. I understand that. But it is easy to maintain. For example the chest freezer died in Portobello Panama. A tiny town. The Chinese grocery store in town had a direct replacement for a whopping $225. That's almost less than a service call to check out a problem with a marine system, let alone find the parts and conduct a repair! Plus we had it fixed the same day without trying to find a technician which could take a week in many places plus a reposition plus a marina visit. Finally we like it since the systems are redundant. If it could not be fixed right away, the fridges back each other up as do the freezers, albeit with reduced capacity. So life can go on for awhile since its not yet a crisis. So you get the idea.....

Some folks over a Home Power have been rebuilding LI batts for a couple of years now.

Actually they don't rebuild , just get a batch , take them apart , toss the bad cells and reassemble.

With a couple of thousand LI cars getting near the batt replacement mark , it might be cheaper than dirt to do the same.

Really depends on the recycle value, wet LA batts are easy so an old 8D is $55 bucks.

Wonder if the LI will be recycled or buried at the dump?

Years ago I had a 40' Penbo trawler - made of, Gasp! Wood! The only power was a 454 GM diesel. Refrigeration was mechanical with the compressor belted to the engine and to a 120 VAC motor for plugged in cooling.

The box was sailboat style, built in, top loading, freezer next to fridge. To regulate temp in fridge, you slid a plate to control the size of the opening between the freezer and fridge. Cooling plates were in freezer only.

There was no automatic control. When motoring, a switch controlled a magnetic clutch and you monitored temperature in freezer. Like wise at shoreside.

Primitive by today's standards but effective.

It seems to me that other than hot water, it's your plethora of refrigerators, ice makers and freezers that is using the bulk if your battery.

Two suggestions - both suitable for DIY:

1) heat exchanger from engine and genset cooling to hot water.

2) tear out those inefficient fridges, etc , and build a good, really well insulated, box and use mechanically driven compressor(s). With some clever wiring, you could even have the thermostat start/stop the generator? You can buy just the ice maker device and install in new freezer.

An induction cooktop wouldn't hurt. Just a cheap hot plate style.

If you don't want to build the boxes but have room for a 72" tall unit, our Hitachi 14.5 cu.ft. Hardly uses any power - I'm sure less than a single under counter 5 cu.ft. one. And it makes ice too.

rjtrane said:

The only power was a 454 GM diesel. 453??
It seems to me that other than hot water, it's your plethora of refrigerators, ice makers and freezers that is using the bulk if your battery. Yes, couldn't agree more. An induction cooktop wouldn't hurt. Just a cheap hot plate style. What are brand names to consider? .

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It is amazing what people pack onto boats. We've some friends that do extended water travel with Golden Retrievers on their KK 42. They have a full size chest freezer for dog food in the cockpit.

E boat travel may well be limited due to human nature to collect heavy crapola, have unlimited ice for drinks and freeze steaks.

If your not into DIY, then consider Engel. ENGEL USA - AC/DC FRIDGE/FREEZERS | PERFORMANCE COOLERS - - AC/DC FRIDGE/FREEZERS \| PERFORMANCE COOLERS

The Engel is a great quality product. Some friends we go 4-wheeling with use them and have no regrets.

Craig, they are a bit pricey, but for a portable have good insulation and a efficient motor/compressor. To see this efficiency https://www.engel-usa.com/images/stories/pdfs/MT45F_Performance_chart.pdf

An example, the 45 quart fridge/freezer

In fridge setting, ambient temp 25 degree C, box temp 5 degree C would consume 40 w-hr per 24 hours, not much at all, a single 15 watt solar panel feeding the battery would cover this.

However, if ambient temp is hot at 35*C and you want to use as a freezer at -12* C, then 24 hour consumption would be 691 w-hr. That would require a 150 watt solar panel feeding the battery to handle the 24 hour energy consumption.

We had a custom box built to our insulation and space requirements. We cruised on a sailboat few for 10 years with a cold plate system and felt that the newer evaporative plate systems were more efficient. We have 4" of insulation with 3" in the doors and 2.5" between the freezer and refrigerator. A Danfoss BD35F compressor for the fridge and a BD50F for the freezer. Both utilize the same electronic module. We can leave the boat for 5 days at anchor and use less than 105 amps per day, total. Our house bank is 1100 amps with T-105's so are using less than 50%. Solar and or wind maybe be the next addition to help reduce the generator run time which is now less than 2 hours per day. Sea Freeze, Bellingham, WA did the build for ~4 boat units.

Clean and efficient set up Larry. Is a "boat unit" $1000? So $4000?

deckofficer said:

Clean and efficient set up Larry. Is a "boat unit" $1000? So $4000?

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Bob: break out another thousand = "boat" unit.

I should have mentioned that our fridge is a little over 5 cubic feet and the freezer is 2.5. I could go bigger on the fridge if space allowed it but not much. The freezer size has been perfect.

A second 2.5-5 cubic foot fridge, if it looked like it belonged, would be a plus. You could shut it off when it's not needed so you wouldn't be trying to cool air. After a major provisioning run, space is at a premium.

FF turned us on to Sun Frost. We recently met a cruiser who had replaced their household unit with one of their units and all was positive but he had no real numbers yet. Next time I would look at Sun Frost also.

Sun Frost energy efficient refrigerators

I've known and used Sun Frost back when I was designing off grid power for remote homesites 25 years ago. Expensive, but over their life will fully return your investment in savings on electricity.

I'm also a fan of two smaller freezers for provisioning then shutting one down when it is emptied. That is another reason I like the Engel portables which can be set as a freezer or fridge. When the 2nd Engel is emptied of frozen food it can be set as a fridge to keep drinks cold when you are entertaining a boat load of guests, then when there gone, unplugged again. Good flexibility.

Larry M said:

Bob: break out another thousand = "boat" unit.

I should have mentioned that our fridge is a little over 5 cubic feet and the freezer is 2.5. I could go bigger on the fridge if space allowed it but not much. The freezer size has been perfect.

A second 2.5-5 cubic foot fridge, if it looked like it belonged, would be a plus. You could shut it off when it's not needed so you wouldn't be trying to cool air. After a major provisioning run, space is at a premium.

FF turned us on to Sun Frost. We recently met a cruiser who had replaced their household unit with one of their units and all was positive but he had no real numbers yet. Next time I would look at Sun Frost also.

Sun Frost energy efficient refrigerators

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I looked at Sun Frost before we left. Mostly for their freezers since we expected to replace that unit. But they are not that different in efficiency, the 3.9 CuFt SF model is rated at 164 kWh a year where there are several 5 CuFt "normal" chest freezers rated at 193 kWh a year. By government Energy Star testing. The Sun Frost F4 is $1500, the small 5 CuFt chest freezer $200-250.

The Energy Star program has resulted in ordinary refrigerators and freezers becoming much more efficient.

deckofficer said:

Craig, they are a bit pricey, but for a portable have good insulation and a efficient motor/compressor. To see this efficiency https://www.engel-usa.com/images/stories/pdfs/MT45F_Performance_chart.pdf

An example, the 45 quart fridge/freezer

In fridge setting, ambient temp 25 degree C, box temp 5 degree C would consume 40 w-hr per 24 hours, not much at all, a single 15 watt solar panel feeding the battery would cover this.

However, if ambient temp is hot at 35*C and you want to use as a freezer at -12* C, then 24 hour consumption would be 691 w-hr. That would require a 150 watt solar panel feeding the battery to handle the 24 hour energy consumption.

Click to expand...

Energy cost per CuFt is similar to my 5 CuFt freezer. It takes 3 of these Engle units to equal a single 5 CuFt chest freezer, unless I messed up the math converting quarts to cubic feet. So it looks like you could expect something like 6A contin draw at 12V in the tropics on Engle, our chest freezer draws 9A DC via the inverter when the compressor is running. But it does not run a 100% duty cycle. Probably 70-80%.

There is probably a slight edge to the Engle, but a rounding error compared to the price difference.

Larry M said:

We had a custom box built to our insulation and space requirements. We cruised on a sailboat few for 10 years with a cold plate system and felt that the newer evaporative plate systems were more efficient. We have 4" of insulation with 3" in the doors and 2.5" between the freezer and refrigerator. A Danfoss BD35F compressor for the fridge and a BD50F for the freezer. Both utilize the same electronic module. We can leave the boat for 5 days at anchor and use less than 105 amps per day, total. Our house bank is 1100 amps with T-105's so are using less than 50%. Solar and or wind maybe be the next addition to help reduce the generator run time which is now less than 2 hours per day. Sea Freeze, Bellingham, WA did the build for ~4 boat units.

Click to expand...

I agree that this is probably the best solution to minimize energy usage. It accomplishes what none of the pre made solutions do, much thicker insulation and the ability to channel the waste heat away from the box. Like the Engle it eliminates the inefficiency in converting 12V to 120VAC using Danfoss compressors, and can be set up for variable speed.

Further it can be optionally set up with holding plates and an auxiliary compressor for when the generator is running to reduce the battery requirement when it's not.

The "pig" in our setup is the ice maker. It draws 20A for the compressor and again when it's runs the "heater" to release the ice cubes. This is at least 1/3, if not 1/2 of our refrigeration load. One so far, we've been willing to pay for.

In our situation it came down to the 2-3 year cruising plan, then a plan to go back to work, living aboard in a USA marina where none of this matters. The time period was not long enough to justify the 4-5K investment when we looked both before we left, and once again in St Martin when we realized we were killing the battery bank.

To solve the problem in St Martin, when we last looked, required at least 5K in refrigeration and cabinet modifications, 3K in solar and 2K to replace our already almost dead batteries. With lots of potential for scope creep. And giving up the ice maker, did I mention we like that?

So instead we went with a LiFePO4 battery bank at 7K and kept the rest. It was a sub optimal solution, but it looks like it will work out. We just aren't the most efficient cruiser in the anchorage. Before we go out again in a few years, it will be time to see what makes sense then.

rjtrane said:

Years ago I had a 40' Penbo trawler - made of, Gasp! Wood! The only power was a 454 GM diesel. Refrigeration was mechanical with the compressor belted to the engine and to a 120 VAC motor for plugged in cooling.

The box was sailboat style, built in, top loading, freezer next to fridge. To regulate temp in fridge, you slid a plate to control the size of the opening between the freezer and fridge. Cooling plates were in freezer only.

There was no automatic control. When motoring, a switch controlled a magnetic clutch and you monitored temperature in freezer. Like wise at shoreside.

Primitive by today's standards but effective.

It seems to me that other than hot water, it's your plethora of refrigerators, ice makers and freezers that is using the bulk if your battery.

Two suggestions - both suitable for DIY:

1) heat exchanger from engine and genset cooling to hot water.

2) tear out those inefficient fridges, etc , and build a good, really well insulated, box and use mechanically driven compressor(s). With some clever wiring, you could even have the thermostat start/stop the generator? You can buy just the ice maker device and install in new freezer.

An induction cooktop wouldn't hurt. Just a cheap hot plate style.

If you don't want to build the boxes but have room for a 72" tall unit, our Hitachi 14.5 cu.ft. Hardly uses any power - I'm sure less than a single under counter 5 cu.ft. one. And it makes ice too.

Click to expand...

The hot water heater was plumbed to the propulsion engines until it burst in Panama due to old age. It did help on travel days, but only the day of arrival. I like the genset idea, free heat! Have to look at that when we get home, it will require moving the heater since its on the opposite side of the engine room now. The $100 fix in Panama was a 3 gallon electric only unit from the Home Center. Until you get down here, it is hard to imagine the difficulty getting marine stuff without paying 30-50% more than at home, and having to wait weeks to get it.

I had the mechanical engine driven systems on a few bareboat charters. It worked pretty well, but you had to run it twice a day without fail or end up thawing the freezer. The market seems to have moved away from this as Larry already mentioned. What you could do is have a really good sized AC electric compressor tied to the holding plate. Normally only run with the generator, but if absent run off battery power. Im not sure it would be better than solar/battery powered Danfoss. If you want to tie genset starting to energy depletion, my Xantrex/Trace unit has that built in already, but I am leery of this unattended and don't use it.

I love the idea of an induction cooktop. Did some research when you mentioned it a few days ago. Someone needs to make a stove sized to the Galley Maid dimensions with induction cooktops. We may update the galley for the Admiral when we get home and I'm going to look at this more. She still wants 3 burners and that's going to be a challenge to fit.

If I can find the space, a full size refrigerator is worth considering.