Experience with refrigerators on extended cruises?

[Night Sailor]

Any refrig/freezer unit will run less often if at least two more inches of insulation is added to the pretty packaging the unit comes in. And keeping it in the shade helps tremendously.

I'm reluctant to have any necessary piece of gear exposed in the cockpit to thieves while I'm off the boat unless it is bolted down securely, or easily replaceable in any port. Things disappear more often in remote areas where the median income is a few hundred dollars a month, if that.

That said, if mounting a well insulated fridge in the cockpit or stern I'd build a strong box for it, lined wth radiant barrier, with ventilation as necessary, with a good lock on it.

More batteries greatly increases the usefulness of a solar system so what is not replenished by solar or motor can be drawn down from a larger battery bank. The more batteries you have, the lower in volts and amps you can go before needing to recharge. I only have 100 watts going to four Optima batteries. We run a thermoelectric Koolatron 35 sitting on the aft galley seat. It runs constantly, but I turn off at night when going to sleep because I've added more insulation and it just doesn't lose much cool if not opened in the cooler night time temps. It has a battery saver in line that shuts it down if battery voltage should ever get so low that we couldn't start the engine or run other euipment.

We learned back in the '70s while beach camping in open daysailers in FLorida and backpacking for weeks in the Appalachians that we don't need ice for anything. Nice, yes, but not a need to have fun and drink and eat very well. That saves us a lot of amps now.

[Moe]

Someone gave me one of those thermoelectric coolers they used a couple of times for a cross-country trip. It drew a whopping 8 amps and would run a battery down in very little time! I wound up pitching it. The compressor types are a lot more frugal, but I don't disagree with keeping them out of the sun.

Personally, for long term cruising, I'd take the Lynn and Larry Pardey approach of no refrigeration.

[James V]

I was trying to find the site that has a good boat frig and has much insulation and can be bought with solar pannels. I could not find it but if you do not have good insulation on your fring with temps above 70 all the time you will need some big batteries to handle it at night or when you leave the boat during the day. Battery size, don't remember the formula but if you need 3 amp per hr, so 36 per day that is 1 stock battery just to handle the frig and 3 - 5 hrs to charging the battery with the motor per day.

These are not cheep. A lot of people jsut buy meat when theay are in town and go without when away.

The same with cold drinks.

[KayakDan]

Good question, It depends on IF you use your stereo much or you computer. Still your engin puts out enough to give a quick charge if needed. As long as you have good sun you should be OK. Today I droped to 11.6 on one battery with mostly cloudy day. The computer takes 10 to 12 amps to charge and use.

I have 2 - 20 W pannels. Winds was shifting.

Part of my reasoning is no chartplotter needed while I'm on the hook,and the stereo might run an hour or two a day. Lights draw next to nothing,including the anchor light(all LED's)

[Duane Dunn, Allegro]

Mallardjusted,

Yes, I am getting a new motor for our boat. There is nothing wrong with our Tohatsu 50D other than noise, smoke and poor fuel mileage, but I have been presented with a deal I cannot pass up. (If anyone is looking for a super deal on a used 1996 Tohatsu 50D in perfect working order let me know. It could be had real cheap to a good home.)

I got a call in December from Todd at BWY asking if I would be interested in developing a new section of their web site. They have made a deal with Roger and the Mac factory to be the source for all out of production parts for Macs and Ventures going back to the late 60's. The factory has shipped them every out of production, left over, and spare part they had as well as the purchasing information and specs needed to aquire more parts. If you call the factory and want a part for any boat except the current model in production you will be refered to BWY. We're getting close to putting up the parts catalog.

As part of our conversation we talked about what I would want as compensation. At this point there isn't a whole lot of additional stuff I need for Allegro, and while I mentioned a desire for a motor I knew there was no way what I was doing would add up to what a motor costs.

A few weeks later Todd called to say he had something to offer if I was interested. Stored in a crate at their shop he has the 2005 Tohatsu 70 hp TDLI that he originally installed on Pearl. He tested it as both a 70hp and a 90hp to see how the boat responded, but eventually took it off in favor of the Suzuki 70 now on Pearl. Almost all the boats they sell have four strokes so it made more sense to have that on Pearl.

Todd thought he had it paired up with another M he was selling, but that turned out not to be the case. He offered it to me at a very good price, and minus what he owes me for the website work it presented a way to upgrade our motor for a price that was too good to pass up.

So that's the long way to say, Yes, there will be a new, very strong motor on the back of Allegro shortly. I'm looking forward to all the extra benefits these new generation two stokes have to offer.

[James V]

Sounds good. It has been cloudy about 1/2 the day here.

100W sounds about right. Supplies are just to easy to get here although a bit expensive to tu shipping and import duties and taxes at 42%. The Bahamaians have no income tax and the import taxes is what is used.

You may want a deticated battery for the frig so that you can have the others for your needs and a way to charge it with something else like the motor or a small gen. We have had 2 days in a row of clouds and little or no sun to not make the solar pannels work.

[hvolkhart]

For our 2 week trip I’m planning to be a max of 4 nights in a Marina. Therefore I’m trying to calculate the power requirements / consumption on a 24 hour cycle.
Below please find a table I was putting together with all consumers as well as the average usage time per 24 hours.
I also have stated the storage capacity for the power in an 80 amp battery. I don’t like to use the starter battery as a calculated power source.
In order to generate the required power, I’m using a 50 HP Mercury.




Power storage
House Battery 80.0 amp hour
Starter Battery only for starting motor 45.0 amp hour


Power generation
Motor 50 HP Mercury
19 Amp @ 4000 rpm 1 hour run time = 19 amp
10 Amp @ 2000 rpm 2 hours run time = 20 amp
2 Amp @ idle .1 hour run time = .2 amp
Total = 39.2 amp

Please comment on the table and any suggestions on additional power and how to generate.
Thank you

[Boblee]

We have been using a 70lt Evercool fridge/freezer (Danfoss) mounted opposite the head in our it has a factory cover and is run off 2x70amp hr wetcell batteries one mounted under the v berth and one beside the factory starting battery below the ladder which can also be switched to run the fridge in an emergency, they are all linked with 35mm cables.
They are charged using two 65w panels above the stern (in mods http://macgregorsailors.com/cgi-bin/mod ... record=856) through a regulator, we can also charge all batteries with the motor (evinrude) or with a 25amp charger from 240v.
I worried about whether this would be satisfactory in the tropics but with 3 weeks travelling down our Murray River with weather ranging from 40c + to raining and overcast in Feb last year we never even had the slightest concern and never used the charger and used the motor only when we thought of it.
We used the system again last year for three months travelling up our East coast and we rarely had to consider checking voltages, even when cruising the Whitsundays for three weeks in mid winter but still 20-30 deg.
We have had smaller trips including 5 days last week and the batteries never got below 12.2 v despite parking in shade for most of the day and not using the motor or only when we moved and thought to switch it over.
When travelling on the road we can charge from the tow vehicle also.
I believe the panels being where they are helps considerably as even with the mast laying across them we still get up to 4 amps charge.
There is no way I would not have a fridge as once set up it is just too convenient, especially in our circumstances.
Note we also run a 600w inverter for the computor and misc 240v battery chargers, a 12v fan extra lights including cockpit, we run raymarine chartplotter and sounder and will probably for travelling in our far northern waters for long periods install radar but almost definitely an auto pilot, most likely a Raymarine, vhf and uhf radios and cd/am/fm radioand water pump all get used fairly well.
Hope that gives some ideas.

[Moe]

hvolkhart, check your email.

[Catigale]

My Merc 50 shows it outputting the full 200 Watts (18 Amp) at 2000 rpm so you might be doing better than you think there. That being said, you have to back off the EFI control unit current draw from your amp ratings on the motor - a number I have been promising to measure but still havent gotten AROUNDTUIT

[James V]

The output from most motors is not constant amps. the lower the voltage the most amps is put out, when you get closer to full charge the lower the amps. Inboards have a special regulator to handle this. From what I have been told by Merc, you cannot put one on the outboard.

I do not beleive that the solar regulators do this but will cut off when fully toped off, Anybody have any data on them?

[Catigale]

Thanks James that makes a total of three issues

1 The available current/power from the alternator as function of rpm.
2 The overhead of the EFI control unit (pretty much independent of rpm)
3 The actual current/power delivered to the battery as a function of battery charge state.

that you need to consider to calculate your 'putback' rate.

[hvolkhart]

Moe,
Thank you for your explanation. It is very helpfull. However, I still have to study it a little further and will post my finding.

[Chinook]

Thanks all for your collective wisdom on powering a refrigerator. Good points both pro and con. After much pondering, I've decided to proceed with purchase of the Engel 35 for our spring cruise on the Sea of Cortez. Based on comments here, I may be a little light on power capacity. I have about 100 amp hours of usable house power, plus the 65 watt solar panel. Sounds like 100 watts would be preferable, but I'll try to compensate with efficiency and close monitoring. I'm switching my anchor light and cabin reading lights to LED bulbs. I'll directly wire the frig into the battery, instead of using the 12 volt plug fitting. I'll add insulation around the exterior of the frig, and install ventilation cutouts for good air circulation. I will use the max/min thermometer with remote probe to monitor internal temp, and will try to operate in the low 40 degree range, which will hopefully keep my draw down to under 2 amps, when it is cycling. I figure the periodic operation of the outboard will also help keep the batteries up. And since this will all be new, I'll use the old Coleman cooler as a storage container, and available to serve as a backup icechest in a pinch. I'll post an after action report on how all this works out after we return, around the first of June.

[James V]

It has been some time, but you may want a little cooler temp's if you want to keep meat. Somewhere around 34 degrees more or less and install a fuse or breaker. I have a main 40 amp breaker right after the battery switch.

Sounds like a plan and it should work out.