Build a 12 volt sous vide

[valhalla360]

Sounds like a whole lot of complication and unless you have a really bad inverter, you won't gain anything.

Then again, we've got some friends who are into it...nice for chicken breast but otherwise, nothing special. Bigger issue I see is a lot of options take hours of cooking eating up lots of amp-hrs.

It makes sense to use them at restaurants because they can have 3-4 vats of steaks all cooked at different levels of done-ness and ready for a quick sear without having to monitor multiple steaks on the grill and able to send out to the floor in minutes.

[owly]

Originally Posted by valhalla360

Sounds like a whole lot of complication and unless you have a really bad inverter, you won't gain anything.

Then again, we've got some friends who are into it...nice for chicken breast but otherwise, nothing special. Bigger issue I see is a lot of options take hours of cooking eating up lots of amp-hrs.

It makes sense to use them at restaurants because they can have 3-4 vats of steaks all cooked at different levels of done-ness and ready for a quick sear without having to monitor multiple steaks on the grill and able to send out to the floor in minutes.

You clearly have no real experience or conception of what it can do.... or the energy consumption. A sous vide uses very little power if it's in an insulated container. You are cooking at very low temperatures. For example a medium rare piece of meat is cooked at 130 deg F, chicken around 140 to 145. Heat loss is extremely low due to insulation and no evaporation as in boiling. It takes very little energy, and the result is a perfect product every time. Exactly the state of done-ness, exactly the ideal texture. For example I did some califlower last night at 180, which is about as high as I ever cook anything. It was put in a bag, seasoned with a little olive oil and some Worcestershire sauce and spices. It came out absolutely perfect, with good texture still, and with full flavor. A quick pan fry for just a minute or two to brown the surface and develop the malliard reaction bringing out the natural sugars. You simply cannot achieve the kinds of results you get with sous vide using any other cooking method. A medium rare steak is medium rare from one side to the other, excepting the surface that you sear afterward. It's as tender as you choose to make it.... a function of time. It looses no moisture or flavor in cooking. A marinade will permeate nicely. Tough steak or fish, or foul can be made melt in your mouth tender, while still retaining it character. Buy a leg of billygoat in a village market, tough as nails... sous vide cook it for a long time, and you end up with a cut of meat like the best leg of lamb. Wild game really shines in sous vide. It's an amazing tool, and contrary to your assertions it does not consume a lot of amps if you use it properly.

One advantage of sous vide onboard is being able to use electrical energy as it is being produced, rather than sucking down batteries. Low energy, long cooking results in unprecedented control, and removes the stress of cooking in many ways. Put it and forget it..... You can't overcook, so if dinner is ready about the time you need to do a sail change.....no big deal.
Until you use one for awhile, you have no conception of it's real value. It does far more than you think.



H.W.

[valhalla360]

Originally Posted by owly

You clearly have no real experience or conception of what it can do....

Nope, very well aware as we have a few friends who are really into it and they go on and on about it.

Again, works great for Chicken Breast where it's easy to overcook and dry it out and for restaurants who need to turn out lots of steaks really quick and have the done-ness very reliable.

But for other stuff...I haven't been overly impressed. Seems like extra effort for not a lot better.

As far as energy consumption, even if you assume a fairly modest duty cycle, it's a lot of amp hours and even though it's not coming out of the batteries...it's also not going into the batteries. Most of the basic ones run around 1000w and only a 25% duty cycle because you did a really good job insulating and it takes 5hrs...that works out to around 100amp-hr before factoring in losses. Of course, you could home build something with lower wattage but then the duty cycle will go up proportionally, so you don't really gain anything.

Also this assumes you cook only from around 10am to 2pm when solar is putting out max wattage. If you get side tracked and leave it running until 7pm, not discharging batteries goes out the window.

I would suggest getting one and running it at the dock with a meter on it to measure the actual power consumption because I'm betting you are way under estimating the consumption.

[DMCantor]

Sous vide circulators use 700 watts or more, which is a lot on a boat. I guess, if you have a well insulated container, the duty cycle would be pretty low. On the other hand, cooking some of that tasty island goat meat probably needs 48-72 ours in the cooker. I think our energy budget just can't afford it.

[AndyEss]

You do realize that running electric resistance heating elements is entirely a problem of wattage? Run a heater at 12vdc as compared to 110, and you will need almost ten times the amperage.
A silly solution to a non-problem Mr. Gadget.
As for problems in third world ports, a consumer product manufactured by the tens of thousands will be orders of magnitude more reliable than a hand rolled project.
And I built custom equipment for decades for my business

[Simi 60]

Originally Posted by owly

It is more than "one person's opinion". Inverters often operate as low as 75% efficiency.

As others have said that would a a cheap, crappy inverter.

. What sort of inverter are you using?

Victron 5000/120

The last thing I want is to be sitting at Noumea or Port Moresby waiting for parts, and dealing with import export issues..

we carry spares for many mission critical areas, more so if travelling remote.
.

. I like simplicity!!

So do I, but I also like convenience and comfort.

[wiwizz]

I sous-vide in a foam beer cooler. If you want elegance, gold leaf it.

tony thomas

[KimSails]

I have never heard of sous vide cooking until this post, so definitely not an expert about this process, but I like the idea.

Assuming it is sized to cook food for just a couple of people, I have a hard time understanding why a circulating pump would need to be more than a few watts. If you are in the tropics I wouldn't think that a heating element would have to work all that hard. Particularly if you pre-warm the unit in the morning sun and keep it well insulated with a black exterior to absorb the sun's heat over the day. If you have excess solar, you'd be cooking for at, or near, free.

IDK, maybe it won't work for some of the reasons stated, but I'd like to hear about the results if you try!

Many years ago there was a chef/restaurant owner of a nice restaurant in my town. He was known for cooking food in unusual methods while traveling. For example, wrapping a fish filet in aluminum foil with some spices and lemon and putting it on the cylinder head of his engine while he drove. In a couple hours he had a nice meal. Seems to me that cruisers can be rather inventive in the same way.

[Jdege]

Originally Posted by Thalas

Crock pots are great, but the results always tend towards homogenizing the individual flavors. That’s not always bad, but sous vide is a brilliant idea on a boat. Individual flavors, cooked to perfection, and best of all, should an emergency arise (as is wont to happen on a boat), you have all the time in the world to address it and then come back to your meal.

I sous vided in a crock pot for years. All you need is a stupid pot without electronics, and a temperature controller that can turn it off and on. Fill it with water, drop in the thermocouple and the vacuum sealer bag, plug it into the controller, and wait.

I'm still sous viding the same way, except I'm using a rice cooker instead of a crock pot.

[owly]

Originally Posted by KimSails

I have never heard of sous vide cooking until this post, so definitely not an expert about this process, but I like the idea.

Assuming it is sized to cook food for just a couple of people, I have a hard time understanding why a circulating pump would need to be more than a few watts. If you are in the tropics I wouldn't think that a heating element would have to work all that hard. Particularly if you pre-warm the unit in the morning sun and keep it well insulated with a black exterior to absorb the sun's heat over the day. If you have excess solar, you'd be cooking for at, or near, free.

IDK, maybe it won't work for some of the reasons stated, but I'd like to hear about the results if you try!

Many years ago there was a chef/restaurant owner of a nice restaurant in my town. He was known for cooking food in unusual methods while traveling. For example, wrapping a fish filet in aluminum foil with some spices and lemon and putting it on the cylinder head of his engine while he drove. In a couple hours he had a nice meal. Seems to me that cruisers can be rather inventive in the same way.

A lot of people are inventing numbers here.... out of "whole cloth"..... imagined percentages, etc. In reality it takes very little energy to maintain those low temperatures. Suggesting that the element is going to run 25% of the time is beyond absurd if you look at the basic thermodynamics of the situation. The element is sized to rapidly come up to cooking temperature... and they do. Computer programmers have had a saying for many years.... garbage in garbage out. When people pull numbers out of blue sky (to be polite... there is a cruder and more appropriate term). Unfortunately I don't have a recording amp meter, just a clamp on digital meter. I'm running my sous vide at 185 at the moment... much higher than one cooks most things. The idea was to record on time, but that's impossible, as the on times are so short, so short in fact that the display can't keep up....... My scope meter unfortunately is not set up for a clamp on inductive sensor, but it would be difficult to get anything intelligible on a scope anyway, as thing vary constantly. It looks like the controller is pulsing the element, but it's impossible to quantify when the reaction time of the display can't keep up. The scope meter does handle 20 amps max in the current setting, but I don't have a way to rig it inline. It would be interesting to observe on a scope, not not especially useful. From what I see, it operates kind of like a PID controller. The circulator consumes more power than I would have suspected at 19W (approx)
In any case I would probably preheat the water on the stove. the heating element in a home built unit needn't be very big if you aren't trying to heat several gallons of cold water up to temp rapidly.



The 12 volt crock pot idea is an excellent one... a great place to start... circulating is important for uniform cooking


Someone commented that every watt being used was a watt not going into the batteries........That's actually a good thing in many cases. Batteries ability to take charge tapers off, and many times the amount of power the solar panels are supposedly producing is far in excess of what the batteries are actually able to absorb, so there's a lot of waste in a solar power system. Every watt that can be used directly is a watt that doesn't need to be stored. Battery life is inversely proportional to watts in and watts out. I've advocated making ice while the sun shines to reduce battery usage, and the size needed. Water doesn't wear out no matter how many times you freeze it, and the energy cycle of freezing and thawing has greater efficiency than battery storage, and about the same energy density.



H.W.

[sazarac]

The Insti pot brand has a 12 volt circulation motor. I see the units for around $80 US.

[valhalla360]

You can get a plug in meter for $10-25 (kill-a-watt is a common brand but many are around)...it measures total watt-hr.

As a first pass 25% duty cycle seems very realistic as a first pass but maybe they are better.

Unless you oversize your solar array, I don't see any advantage to cooking during the day...if you are oversized that much, cheaper to trade out a smaller solar array for an extra battery.

But hey, have fun with you experiment and let us know how it goes.

[44'cruisingcat]

Originally Posted by owly

A lot of people are inventing numbers here.... out of "whole cloth"..... imagined percentages, etc.


H.W.

Like the 75% efficient inverters?

[john61ct]

Originally Posted by owly

A lot of people are inventing numbers here.... out of "whole cloth"..... imagined percentages, etc. In reality it takes very little energy to maintain those low temperatures.
…
Unfortunately I don't have a recording amp meter, just a clamp on digital meter.

Reasonably accurate AH counters can cost as little as $20-40.

Actually measure AH consumed cooking X meals for Y people over 24 hours.

And useful for many other purposes improving your electrical setup from an objective systems approach over time.

[john61ct]

Originally Posted by 44'cruisingcat

Like the 75% efficient inverters?

Yes. A mains-style AH counter like Kill-a-Watt on the load side

a DC version on the bank showing total energy draw. Obviously converting both to watt-hours,

will show many even expensive inverters have **much** lower overall conversion efficiency IRL than the number cited by the manufacturer.

Especially over 24-hours when users leave them on standby all the time.

For those with limited energy inputs, especially with smaller boats living mostly on the hook,

you're much better off going native DC or diesel / propane whatever, whenever possible.

For the few truly required mains devices left, a smal (maybe cheap) dedicated inverter selected for that device, both get turned on and off together

will save an enormous amount of power over time.

Of course those first-worlders on bigger boats desiring all the mod cons, often plugged into shore power or running ICE every day, this approach will be denigrated as a "camping" lifestyle.