Experience with refrigerators on extended cruises?

[Night Sailor]

Chinook I think your plan is sound and will do fine if you take all the steps outlined. Keeping the refrig unit out of the sun, even if in the cabin, will help also.

If you can find a way to turn that 65W panel toward the sun as it transits each day while at a dock or on a straight line two mooring stituation, you will get maximum results. Aim the panel south and tilt about 26 degrees from horizontal to average the laititudes of the whole Baja peninsula which runs about 23 to 29 degrees, or tilt to the same degree as your current latitude at the time if you have a precise way of measurieng angles.

If maintaining a constant position is not possible, or if underway, a horizontal positon will reduce wind resistance and still make juice, just not quite as effectively due to reflection from the glass surface.

I will definitely also consider an Engel 35 when the time come to upgrade for the next long cruise as the low .7 amp hr requirements for refrig alone just can't be matched by anything else I'm aware of.

After reading all of the Alaska voyage and remembering my own visits there in larger boats, I'm eager to read of your next adventure. Thanks for sharing your triumphs and your goofs so we all learn how from your experiences. The detail you included about fuel and oil consumption at various rpms and loads with and without sail help was very useful for planning. Please continue that level of sharing. Best of luck and happy sailing to you.

[Divecoz]

Off The Kroger Web Site.
When storing meat the temp should be no more than 40 degrees.
They said this as well. It's best to wrap everything individually and do it well to reduce cross contamination . Careful how long you store in the fridge. It seems 2 to 3 days is starting to push it, at 4 or 5 you should start tossing it. Dang come to think of it I should be DEAD then!
Hey Dude The Pizza in the Fridge how old????
Last week some time
Whos is it?
Who cares eat it.. . . .
With these small fridges we should not see the dreaded black hole in the back corner....

[Catigale]

Ive kept meats for 5 days in an Igloo with just ice - starting with the meat frozen at first of course..has been fine.

A 5 day cruise is easy to do without refrigeration imho..

[Divecoz]

Freezing before hand, I would think changes everything. This was more store to fridge and no doubt some CYA tossed in there as well.
My concern was more towards minimum / highest temp they suggest for storage. Every degree you can safely raise the thermo saves a little to a lot of electric

[Chinook]

Thanks for the kind words, Night Sailor, and also the comments on tilt angle. I've mounted the panel on the sliding hatch, but am now thinking over some simple ways to tilt and aim. It shouldn't be too hard. I will be keeping a similar journal and we'll take lots of digital pictures. I think I can impose on #2 son to assist in getting them posted.

Regarding meat refrigeration, we've done the ice chest and frozen foods thing for many years, with most experience on extended canoe trips. 5 days is about the max we've been able to do with ice and pre-freezing. We have had luck extending that by using dry ice. I like to throw a bunch of ice cubes into the bottom of an ice chest that has a drain valve. Above that I place our hard frozen foods, and on top I put about 10 or 15 pounds of dry ice, tightly wrapped in several sheets of newspaper. I seal the chest shut with duct tape, which contains the CO2 and slows the loss of dry ice. After about 3 or 4 days I start checking the valve. When water starts draining out, I know the dry ice is gone, and the hard frozen food is beginning to thaw. From then on, the contents act like regular ice and chilled food items. This extends fresh foods on the menu well into the second week. It's pretty nice to be able to grill a steak 6 or 7 days out, while everyone else is eating freeze dried.

We like to seal frozen meats and such with our vacuum seal-a-meal. That does a good job of keeping things fresh. Zip loc bags are also handy. We're really looking forward to getting away from the grayish, water logged cheese floating around in the ice chest melt water.

[rockman]

Why not add a bigger solar panel to the back of the boat (I will post my setup soon). I have 120W - it runs everything really well. But it is a big panel.

[Boblee]

Chinook
Personally I don't think you will have a problem but the point about the engel only using .75 amp hr is really irrelevant, the efficiency of the compressor and the casing and also the amount of times it is opened is much more important.
When travelling with the camper trailer pre we only had one 65w panel which could run the fridge (2.5 amps) and charge the batteries when parked for extended periods but if we had it set for freeze we needed to run the genny for a couple of hr's at night and maybe a touch up in the morning if the batteries (2x 70 amp hr wetcell) went a bit low overnight. but this was in 30deg C plus and on boost during the day (4 amps).
At refrig it cycles fairly regularly and batteries were charged by day end.
A little tip when freezing we would take out all water (ice) and food for the day in the morning and put it in a small esky and then lock the freezer up with fresh water for freezing while panel was charging without opening until next morning if possible.
Using your motor a couple of hours when the batteries are at their lowest (early morning) should see them charged by nightfall.
Even if you set the fridge to freeze during the day on solar and only run for a few hours at night it should keep the food cold till morning, because of the low input with the engels they take longer to draw down than the danfoss, you can only use what you put in.

[Boblee]

Rockman
Where have you mounted your panels? did you make an arch or hang them from the stern rails.

[Catigale]

On the ice/water problem in coolers - we solved that by using frozen milk and frozen lemonade in 1 quart containers for our source of 'ice'

You use up the milk and lemonade as it thaws of course, so that you never have liquid in the cooler!

With hard frozen food in the cooler, and four quart milk/lemonade blocks, I get 5 nights of cold food on the Cape without replenishing ice.

[Chinook]

For Boblee, it sounds like you're using your Engel as both a freezer and a frig. Are you setting the unit so it can freeze ice on the bottom, yet not freeze foods higher up? It would be nice to be able to do this, but I'm not sure how possible it is.

[James V]

it is possible if you pack it with frozen on the bottom and open it often.

[Boblee]

Chinook ours is an Evercool (aussie) with a Danfoss compressor, the cabinets will hold ice for five days as an ice box only without much problem.
As to the freezer/fridge set up it is 70lt's and there is room on a shelf for dairy at one end or before using the separate esky we separated that end off with a piece of polystyrene but they still freeze if left in there -14 deg C.
Now we just put water in bottles as in the previous post and use it as ice for the esky, if we need more for fishing in the dinghy all day will freeze some techni ice (aussie?).
This way minimises opening and shutting the freezer but with the extra solar panel it is just too easy and have never had a battery problem.
If possible give it a try prior to setting off using more power than normal but really with the motor you shouldn't have a problem.
Just make sure that you have enough charge left to last till morning if running overnight and with the Engel would put a low batterry cutout in circuit because they will drain your battery right down (ours is built in at 11.2 compressor voltage).
If it cuts out during the night it should stay cold till morning.
You can come up with all the calculations of usage and input/output you like but you are in reality governed by too many variables eg amount of sun, motor hr's per day (adjustable) and the most critical ones are efficiency, door opening other usage, the best way to test it is to try in practice but as before if it cuts out you should still have plenty of cold if the door is not opened.
We used an engel for years when hunting and they are as tough as old boots being airborne and spinning 360 deg in the back of vehicles many times in 40-48 deg C if you overuse it it just won't be as cold as if you use it correctly and you will have use the motor more?

[hvolkhart]

Here is what I figured out:

My daily power consumption is about 62 Amp hours with all real measurements of each consumer.
The Merc will provide me about 14 Amp hours / Day
A 65 watt Solar panel will provide about 30 Amp hours / Day
With this set-up I’m short of 18 Amp per day.

We start the trip with a fully loaded house battery (80 amp)
This will allow me theoretically to go for 4.44 day’s.
Time to empty the porta-poty , recharge the battery , go ashore.

In order to not drain the battery fully, (only about 60%) it would leave me 2.6 day’s.
So I will install a second house battery let’s say additional 80 Amp. That will allow me the 4 day’s on sea plus I can cover the request from my teenager to charge his cell phone and laptop.
I’m a happy boater.

[richandlori]

hvolkhart

Are you actually measuring 30AH per day from a 65W solar panel or is that a calculatoin?

The reason I ask is that I have been getting at the most 70AH/day from 260W of solar with MPPT controler and being in Mexico with great sun. The unit is rated at 14.2AMPS.

I would think that real life AH from a 65W panel would be closer to 20AH

You are definitely on the right track of doing a in/out budget for AH and not relying on just one source for all your power.

Another thing to consider is that charging efficiency of the outboard motor. Let me give you an idea of what I see using my Link 10 battery monitor, a 105Amp alternator and a 575 AH battery bank. While the batteries are 50-70% of charge the alternator puts out 80-70ish amps...BUT as the batteries get above 80% charged the amps drop down to 20-15! So it would take darn near forever, if at all, to get the batteries back up to 100% on anything except shorepower. I think a standard number to use is that you battery bank will operate from between 90% and 50% in a real world on the water situation.

I would highly recomend a battery monitor with a real time AMP reading for anyone wanting to really keep track of your power usage.

Regards

Rich
S/V THIRD DAY

[walt]

Rich, interesting measured numbers. One question - when you measured the 70 AH/day for the 260 watt panel, were your batteries fairly full to begin with?

Just some rough calcs - but if your panel is rated at 14.2 amps, the MPPT controller should be capable of putting maybe (16/12)* 14.2 amps = 18.9 amps into the battery in direct sunlight.

At 70 AH/day, this says you are only getting an "average" of 3.69 hours of charging per day. Lots of things could affect this such as panel mounting, location and time of year but this seems a little low. But if the batteries were mostly charged, the MPPT controller would cut back on the current.

I think its good advice to have a lot of battery capacity so that you can operate the batteries mostly between say 50% to 85% as under 85% is where you get the most efficiency out of whatever your using to charge the batteries. You can charge to 100% before you leave on the trip.

Edit - I went back and checked some measurements I had taken on my 160 watt MPPT controller solar system (not on a boat) and I was getting between 15% to about 20% higher current out of the controller than is going into the controller. Using 15%, the 260 watt panel current out of the MPPT controller would be 14.2 amp * 1.15 = 16.33 amps. For 70 amp*hour, this is 4.28 hours. Still seems a little low for down in Mexico but I guess the numbers Rich used are probably a good benchmark. If you dont have MPPT (generally only used on larger panels - not what would be commonly used on under 100 watts), you would need to de-rate an additional 15%.

So for the 65 watt panel, using the same scaling and no MPPT, the daily amp hours would be 15.2.