Fridge and watermaker on 27' mono?

[Q Xopa]

Originally Posted by Copacabana

That may be true, but I'm not so sure. I tend to turn the fridge back on when amps in are above the fridge consumption rate of 2.5a. The batteries are still at 12.6v and begin charging immediately (with the increasing amps in as the sun gets higher). I'll have to try both ways to see which is more efficient.

Even if it does use more AHs in a given 24 hr period, it still may work better.
Its matching energy usage and supply patterns better. Using solar while it abundant especially after batts are topped off so it would otherwise be wasted is a good strategy in my opinion.

[Q Xopa]

Originally Posted by Q Xopa

Even if it does use more AHs in a given 24 hr period, it still may work better.
Its matching energy usage and supply patterns better. Using solar while it abundant especially after batts are topped off so it would otherwise be wasted is a good strategy in my opinion.

Of course another suggestion is get more energy storage to get you through the lean times.

Especially if you have adequate solar.

Either batteries or cold plates etc.

[mitiempo]

Originally Posted by Gene Neill

Hmm, interesting. That model is not listed on the US website. Up to .5A higher draw, but MUCH easier to insulate, since the compressor can be mounted remotely. I wonder which one comes out ahead in the real world.

I don't think it exists any more in the US. It is not in the current price sheet either.

The only built-in models they are currently offering are front opening.

[Copacabana]

Originally Posted by mitiempo

I don't think it exists any more in the US. It is not in the current price sheet either.

The only built-in models they are currently offering are front opening.

I think you're right about that, but I have seen a few for sale on sites (probably old stock). I think it's a shame if they discontinue the model as it's the easiest to adapt to boats, in my opinion (that and I won't be able to get a replacement when mine dies...).

[newhaul]

Originally Posted by Q Xopa

Of course another suggestion is get more energy storage to get you through the lean times.

Especially if you have adequate solar.

Either batteries or cold plates etc.

that is true . Here is where you must make some serious decisions. The added cost, maintenance and weight of additional battery storage ( also keeping in mind the life expectancy)
verses the additional cost ( its not insignificant) and potential loss of refer space for the plate .

Advantage is you convert your existing ice box to refer vs losing valuable space with a portable refer system. ( on our small sailboats )

[cj88]

I'm interested to see more details on the new Ozefridge 80L Holdover Fridge & Freezer that only runs once or twice a day. The drawer system will make it easy to access everything without digging through the whole fridge.

http://www.ozefridge.com.au/?page_id=24

[a64pilot]

The swing compressor is a neat concept, it’s basically a solenoid that pulls the piston down against a spring and turns it loose to pull it down again etc.
Fewer moving parts, and due to its design it’s a soft start, no other start is possible. You have to Time the solenoid to the natural frequency of the spring for it to work, in that manner it’s like pushing a kid in a swing, first push small arc, arc gets larger each time only if you time the push correctly.

However due to their operating principle they are noisier and vibrate more.
No matter where you are in my boat, on a clam day or night, there is no doubt when the Engle switches on, contrast that to the BD80 in my Cool Blue, you can’t hear it even if you listen hard, you have to put your hand on the compressor to feel the slight vibration to know it’s running.

While a neat concept the swing compressor isn’t more efficient, and I seriously doubt it lasts longer than a good BD type recip compressor, they often run for decades in constant use.
I replaced our last house fridge when it was over 20 yrs old because the outside had begun to look bad and of course it wasn’t SS like the Wife wanted.
If you assume a 50% duty cycle that little compressor was approaching 90,000 hours of operation. Not even LED light bulbs last that long
http://www.sawafuji.co.jp/english/tech/shindou.html

[Gene Neill]

Okay, the Bimini vs. arch question has been answered, and the arch wins by default. The boom is too low, and the mainsheet is too far forward (or aft, take your pick) for having a Bimini at all, as far as I'm concerned.

So, arches. Just playing around here. This is pretty close to what a pair of 150-170 watt panels would look like, on a prefab "kit" arch (https://www.fishonsports.com/140.htm...ts&modal=false), positioned as far forward as possible. The height is approximate, but I'd like to be able to stand under it in the cockpit.


Thoughts?

[boatman61]

Originally Posted by Gene Neill

Needs to be self sufficient, as we are not marina people.



I think I can mount about 300 watts of solar on an arch or Bimini. (And I suppose I could always rig one stowable panel, say 100W, to use at anchor?) Planning to use two 6V Trojan T105's, 225Ah. We have a 14HP Beta diesel with stock 40A alternator. Willing to lean on the diesel a little, if needed.



I think our worst-case energy budget is 71Ah/day. Unlikely to hit that number on most days, but I like to go by worst case.



Cruising grounds are from central Florida to the Windwards ... so there is high solar potential, but both the the fridge and the watermaker will work harder than in higher latitudes. So I guess that's a wash?


It seems doable to me, if marginal? I assume I should spend some money on the alternator. It is also the area I most ignorant about.



A penny for your thoughts.

If your not marina people I would look at the solar plus wind gens.. always wind in the islands and your charging nights as well.
Just need to find a quiet model.

[Buzzman]

The notion of turning off the power to the compressor overnight is a good one *if reliant on solar to run compressor* - as it reduces overnight battery draw-down.

So for "marginal" and especially lead acid batteries, excess draw down is to be avoided. So although the fridge may, on start up in the morning, remain running for longer to draw down the fridge again, this is being done by 'free' Amps produced from the PV.

Theoretically, if the boat's interior is cool enough for the compressor not to need to turn on (ie: no need to leave it switched on) then it should be OK to leave it on, as it won't cycle. But reality is it probably will in the early hours of the morning.

So switching off the fridge overnight is ONLY worth doing if your battery system is marginal. And yes, the fridge should have an operational low voltage cut-out (from memory 10 or 11 VDC) on the Engel.

The 'drop in' fridege boxes are a useful addition to 12VDC fridges, but even better are the stand alone 'kits' some makers retail that are even more flexible in the shape of the compartment. Some have different shaped cooling plates - flat, rectangular etc - so that it's even easier to fit into a funny boat-shaped fridge.

Some kits come ready to 'plug and play' but have limited length to coolant lines from compressor to plate, others will be too long for your specific installation, so it's best to budget for requiring a tech to do the actual 'hook-up' as it will mean breaching the coolant and thus losing it to atmosphere which is a no-no, environmentally.

Apparently in the US you can purchase coolant and do it yourself, but elsewhere in the world it's more heavily regulated. In Oz you need a Certified Fridge Tech to do the gassing or connecting.

Another option worth considering is the eutectic 12VDC fridge plate. I know there is one company at least that makes a DIY version (not cheap) but the eutectic fluid chills more quickly and retains 'cool' for longer, and thus the compressor cycles less often.

So if contemplating (especially) using a generator to recharge batteries to keep fridge cold (as opposed to PV) then a compressor that cycles less often might mean less need to run the gennie.

We did test one eutectic fridge in the magazine tests, and I have to say the value was questionable. It did not seem to respond all that much better in terms of Amp draw, but the data charts/graphs - from my hazy 20-yr-old recollection, did show less cycling.

However, if I recall correctly, the fridge concerned did not have much additional insulation - other than the eutectic fluid in packs in the walls of the box. So a *properly* and well-insulated eutectic box may in fact outperform (in terms of Amp draw) a more conventional 12VDC fridge of the same capacity.

Don't quote me...

[Don C L]

Originally Posted by Gene Neill

Okay, the Bimini vs. arch question has been answered, and the arch wins by default. The boom is too low, and the mainsheet is too far forward (or aft, take your pick) for having a Bimini at all, as far as I'm concerned.

So, arches. Just playing around here. This is pretty close to what a pair of 150-170 watt panels would look like, on a prefab "kit" arch (https://www.fishonsports.com/140.htm...ts&modal=false), positioned as far forward as possible. The height is approximate, but I'd like to be able to stand under it in the cockpit.


Thoughts?

As an owner of a boat a little larger than yours, I would say, if it were me, I'd prefer to mount panels on the rail that can fold up as needed for charging, and I'd look again at a dodger with panels and a wind generator. I would prefer not to have that windage up so high on such a small boat. Still, though I am encouraged by products and capacities I am seeing in terms of energy production, storage and demand, it may still be too much to ask of a small boat. You may have seen these but here are a couple of shots of folks who have adapted Vegas to long distance cruising. It is a lot to ask of a Vega.

[laika]

Originally Posted by Gene Neill

Okay, the Bimini vs. arch question has been answered, and the arch wins by default. The boom is too low, and the mainsheet is too far forward (or aft, take your pick) for having a Bimini at all, as far as I'm concerned.

So, arches. Just playing around here. This is pretty close to what a pair of 150-170 watt panels would look like, on a prefab "kit" arch (https://www.fishonsports.com/140.htm...ts&modal=false), positioned as far forward as possible. The height is approximate, but I'd like to be able to stand under it in the cockpit.


Thoughts?

That doesn't look bad to my eye. Would they be installed in such a way so as to be easy to strike if the winds picked up? Or would they just be bolted down strong enough to withstand a good blow?

Looks like you would lose the efficiencies that come with being able to tilt the panels, though with 300-350W onboard and a highly insulated fridge maybe that's not a big deal.

Have you searched for pics of what other owners have done?

[newhaul]

Originally Posted by Gene Neill

Okay, the Bimini vs. arch question has been answered, and the arch wins by default. The boom is too low, and the mainsheet is too far forward (or aft, take your pick) for having a Bimini at all, as far as I'm concerned.

So, arches. Just playing around here. This is pretty close to what a pair of 150-170 watt panels would look like, on a prefab "kit" arch (https://www.fishonsports.com/140.htm...ts&modal=false), positioned as far forward as possible. The height is approximate, but I'd like to be able to stand under it in the cockpit.


Thoughts?

I would mount them on the pushpit rail do they can be tipped up or down as needed.
The first picture was on my islander 24. The second is my defender and for comparison I include the mount of panels on a San Juan ( that I recommended not be done)
he later went with my recommended smaller flecx panel on deck .

[cj88]

What about a single pole mounted panel that can be tilted/rotated to maximise input? This is a single 450W panel.

[mitiempo]

Originally Posted by newhaul

I would mount them on the pushpit rail do they can be tipped up or down as needed.
The first picture was on my islander 24. The second is my defender and for comparison I include the mount of panels on a San Juan ( that I recommended not be done)
he later went with my recommended smaller flecx panel on deck .

The problem with these installations is they would be in the way of a self steering vane.