12v rice cookers

[conwy]

I've recently developed a minor obsession with cooking appliances, exploring various kinds of cookers and steamers.

I noticed that there are some rice cookers are sold on Amazon which operate on 12 volts of power, typically 100-200 watt. An example is this "OSBA" branded device.

This kind of rice cooker could be run off a portable camping battery as seen in this YouTube video. The battery could, in turn, be powered off solar for a totally off-grid setup, or you could occasionally power it up via a mains.

It should work well enough for practically any kind of steaming, not just rice cooking. You could use it to make steamed vegetables with some fish, cooked pasta or porridge.

Such as set up would offer certain advantages for a frugal / off-grid lifestyle including:

• Ability to cook outdoors, at a campsite, or even from your car, without always relying on an external power source
• Ability to save on rent by renting a very cheap room, flat or house without kitchen facilities and using this device for all your cooking needs
• Ability to reduce your energy bill by relying on solar energy and/or charging your battery during off-peak periods
• Ability to cook healthy dinners from scratch, with local ingredients, during overseas travel, rather than spending on expensive restaurants or unhealthy fast foods

I haven't yet put my foot down and purchased one, but I'm close to it, as, at ~$50-100 AUD this looks like an excellent investment for someone pursuing frugality and healthy living.

[Slevin]

Seems great. Definitely grab one with a removable pot though (looks like the one you linked the pot is attached?), as without a removable pot seems ridiculous and asking to ruin it with water.

Second question, the whole point of a rice cooker is to boil water, yeah? Isn’t this basically gonna be size limited by the peak power output to boil the water? So it should be good for one person, or maybe two, but it can’t scale well and make rice for later too?

[conwy]

Seems great. Definitely grab one with a removable pot though (looks like the one you linked the pot is attached?), as without a removable pot seems ridiculous and asking to ruin it with water.

I had difficulty finding a 12v cooker with a removable pot which wasn't bigger/bulkier more expensive. There is this one, which is ~23cm² which isn't too bad I guess.

But I prefer the smaller 13cm² model because I like the small form factor for travel (it can fit in my backpack!) I'm also not too fussed about the pot being fixed. Whether it's removable or not, it's still going to need to be cleaned and carefully maintained. I would always soak it in suds for a while after use and then gently wipe off the scraps with a soft cleaning cloth.

But I guess removable means replaceable, so maybe from a long-term maintenance perspective, it's worth sacrificing portability for replaceability.

Second question, the whole point of a rice cooker is to boil water, yeah? Isn’t this basically gonna be size limited by the peak power output to boil the water? So it should be good for one person, or maybe two, but it can’t scale well and make rice for later too?

I guess it'll be a question of the kind of battery, its capacity, how often you can charge it from another power-source such as solar panels or a mains. Also I would definitely like to get a 12v kettle so I can boil water for coffee or tea while porridge is cooking!

[Sclass]

There are 12V pressure cookers on Alibaba too.

[white belt]

You're probably better off just using a thermal cooker. You can cook anything you would normally cook in a pressure cooker, but you only need to use energy to bring water/contents to a boil once. The fully off-grid version could use a small rocket stove to boil the inner pot.

[jacob]

The battery could, in turn, be powered off solar for a totally off-grid setup, or you could occasionally power it up via a mains.

Solar->panel->charger->battery->heater is a very inefficient energy detour. Why not skip the PV part and use a solar cooker directly? (110/220V hotplate for the mains backup)

[conwy]

You're probably better off just using a thermal cooker. You can cook anything you would normally cook in a pressure cooker, but you only need to use energy to bring water/contents to a boil once. The fully off-grid version could use a small rocket stove to boil the inner pot.

Thermal cooker looks potentially interesting, but the problem is, how to bring it to the boil in the first place?

You suggest a rocket stove, which presumably would be fire powered. My main concerns with that are:
1. Health risks from inhaling heavy smoke on a regular basis
2. Legalities around lighting a fire on a regular basis in a dense-urban/suburban area (where I live)
3. Potential complaints from neighbours and/or landlord about the same

But all the above being the case, maybe it would work well during remote trips, occasional use, power outages or if I decide to move to a more rural area.

[conwy]

Solar->panel->charger->battery->heater is a very inefficient energy detour. Why not skip the PV part and use a solar cooker directly? (110/220V hotplate for the mains backup)

Solar cooker - interesting idea. I looked at a few on Amazon, but some of the reviews seemed a bit discouraging. People seemed to say it didn't get hot enough to cook the food properly. But maybe worth revisiting. As you say, one would think a solar cooker would be more efficient given it's a more direct conversion of solar power to heat.

One concern about a solar cooker would be that it might not work so well during winter months or overcast weather.

But it seems definitely worth looking into, if only for the simplicity and environmental friendliness. Probably healthier too with less mass-produced plastic components.

[mathiverse]

Solar cooker - interesting idea. I looked at a few on Amazon...

Consider building your own solar cooker. A box, some black paint, insulating material and some material to prop the box in the proper position is all you need, iirc. They are fairly simple to make.

[white belt]

Thermal cooker looks potentially interesting, but the problem is, how to bring it to the boil in the first place?

You suggest a rocket stove, which presumably would be fire powered. My main concerns with that are:
1. Health risks from inhaling heavy smoke on a regular basis
2. Legalities around lighting a fire on a regular basis in a dense-urban/suburban area (where I live)
3. Potential complaints from neighbours and/or landlord about the same

To be clear, when I said a rocket stove it could mean a small backpacking stove that burns twigs. You can use whatever you want to bring the inner pot to a boil. LPG, butane, alcohol, parabolic solar cooker, induction stove, etc etc. The point is that you only need energy for the amount of time it takes to bring the contents to a boil, then you put it in the thermal cooker and don't need to input any more energy. This is useful if you are trying to get off the grid because it means you only need to input energy for a few minutes a day. The easiest way to mitigate air pollution from cooking is to do it outside.

A regular solar cooker will also work, however it has the downside that you need pretty consistent sun for the entirety of the cooking time, as you point out. The best solution is probably a combination of 2-3 different methods like Jacob said.

Edit: I'd recommend reading through this whole series if you haven't already: https://www.lowtechmagazine.com/cooking/

[conwy]

To be clear, when I said a rocket stove it could mean a small backpacking stove that burns twigs. You can use whatever you want to bring the inner pot to a boil. LPG, butane, alcohol, parabolic solar cooker, induction stove, etc etc. The point is that you only need energy for the amount of time it takes to bring the contents to a boil, then you put it in the thermal cooker and don't need to input any more energy. This is useful if you are trying to get off the grid because it means you only need to input energy for a few minutes a day. The easiest way to mitigate air pollution from cooking is to do it outside.

Ok wow, great ideas! As you say, if it's only used briefly to bring the contents to boil, then that also reduces pollution and conserves fuel (gas or whatever else is used). Nice!

Yes in any case, I would like to do this stuff outside, either in a backyard or BBQ facilities at a park (in Australia we are spoiled rotten when it comes to outdoor public food preparation areas).

A regular solar cooker will also work, however it has the downside that you need pretty consistent sun for the entirety of the cooking time, as you point out. The best solution is probably a combination of 2-3 different methods like Jacob said.

Ok yes perfect. Combining 2-3 different methods also reduces wear-and-tear so things last longer.

I really need to get into a "systems thinking" mindset rather than searching for a silver bullet. I guess this is also part of Jacob's philosophy.

Edit: I'd recommend reading through this whole series if you haven't already: https://www.lowtechmagazine.com/cooking/

Thanks! Will check it out.