12v electric stove OR Rice Cooker in a Minivan with a 12v freezer & 12v fridge for a healthy diet power requirements?

[Lance22]

Right now I have 200watts of solar and a 200ah battery. My only draw right now is my 12v fridge.

I'm interested in electric cooking. be it a stove top or a rice cooker.

I recently discovered I can toss in a frozen bag of broccoli with my rice and they both cook up wonderfully! Next week I want to try cooking my frozen peppers and meatballs with three fresh eggs. If that is a success to then no doubt I can cook my frozen carrots bag with some cheese on top and have pretty much all my healthy meals done right from the rice cooker! Although I still want to have a stove top for cooking meat and chicken but I don't think I would need to use it very often. Plus I could freeze it for long term usage as well.

I think I could upgrade my minivan to have 400watts of solar (maybe more if I see about panels that are more efficient per inch of space ie 180watts instead of 100) Plus I would build my system to support two 100watt pannels to be plugged in during emergencies thought I rarely park off gride so there value wouldn't be so realistic but it be an option for durations of extreme clouds or bad weather. I don't have more space on the roof but I would just mount a frame where I can mount the panels directly too.

I don't have space for more batteries so 200ah might have to be the max. I regularly maintain a USB power banks rotation system. I rotate between six power banks and charge them up when needed. That gives me great flexibility. Essentially only draw at night is the fridge and would be a potential freezer. Plus a USB fan I typically plug into the USB outlet on the fridge which draws directly from the battery. I ony seen my batter as low as some 77% before sunrise.

I don't live in the minivan full time anymore but I would like to figure out how to live in it again but in a means that allows me to maintain a very healthy diet on the cheap.

any help in the numbers or advice in a better method would be much appreciated. When I lived in the van last time I used a butane cooktop. I just rather invest more into my van now to build something that is safer.

 

[maki2]

You have not given us enough information to make informed advice possible. Your battery type matters. For instance I have an AGM 160ah battery but with a margin for safety only 75ah is useable. If I had a LiPO4 battery that was 160ah then I would have 150ah useable. So as you can see we can’t tell you what you can do or what would work best without more information because not all battery types are equal for how much power that is stored in them can be safely used without causing harm to the battery.

 

[Frood]

If you have 200ah (roughly 2400kWh) of usable battery then I don't think you will have to upgrade the batteries. The biggest issue is the solar... It will take roughly 12 hours of full sun to charge up your batteries with only 200w of panels. Do you know how much power your cooker uses? The real question is whether you will be able to recharge your battery with your available panels to keep up with your power usage.

 

[Tesota Overland]

I'm interested in electric cooking. be it a stove top or a rice cooker.

Stove top ain't gonna work, even with a much larger battery bank and regardless of whether they're lead-acid or lithium. Looking at a few cooktops online it seems like even the lowest draw is going to be somewhere around 1200W. Provided your inverter can even keep up with that, for 30 minutes it'd cost upwards of 50Ah. As much as I hate using gas to cook it's hard to beat the energy density, battery tech just isn't there yet. 4xoverland has some YouTube videos where they experiments with electric cooking with mixed results if you'd like more info.

The rice cooker you may be able to get away with (depending on your inverter) assuming you shut it off when everything is done cooking. I've been considering experimenting with this myself, haven't got around to it yet.

 

[Gr8ful]

If you're looking for 12 cookers like sauce pans, skillets, etc they make just about anything for truckers. Type in 12 volt cooker on Amazon & several items come up. I have a 12v drip coffee maker that works great for traveling. For cooking while stationary I'd go with gas myself.

 

[Tesota Overland]

12V drip coffee maker I imagine would work great but you can't get around the laws of thermodynamics. Those 12V cooktops and "ovens" only put out 150-250W, it'll warm food just fine but I wouldn't say you can easily make a meal with them. By comparison, even the cheapest single burner butane gas stove I could find will put out the equivalent of over 2000W.

 

[tx2sturgis]

If you have 200ah (roughly 2400kWh) of usable battery

That would be 2400 wh, not kwh.

 

[tx2sturgis]

I have about 400 watts of solar, and 100ah storage, and yet a large electrical load (such as cooking) will deplete it pretty fast.

You will be limited to morning 'opportunity' cooking, ie, only using it on sunny days when the sun has a chance of replacing what you are pulling out of the battery.

Keep in mind the typical 12v fridge/freezer uses all the energy a single 100 watt panel can produce over a 24 hour period (8-10 hours of sun exposure) during sunny weather and it will take 2 or more of the panels to break even in winter or on cloudy days.

If your cooking appliance of choice is drawing energy for any length of time from a marginal system after dark your system will quickly fall short of your goals.

 

[Lance22]

All interesting information here.

I am interested in meal prep so I'd have some flexibility to when and where I'd be cooking given I would have a few days to plan ahead. I guess cooking meat on butene once a week making 3 fridge meals and 4 meals directly to the freezer would be sufficient plus having a stock of cooked meat already purchased frozen as emergency for a actual rainy day would be perfect way to ensure dependable meals.

Tonight I made rice, broccoli, and some great value meatballs right in the rice cooker! one pot simple meal and it was rather healthy. Plus half a can of tomatoes. Granted I'm making my meals in an apartment nowadays but I'm learning skills for the future I didn't have last time. I always had power with my set up, in over two years I have had my set up From Arizona, New Mexico, Texas, Oklahoma, and even Kansas too, I have only had one day I was concerned about running out of battery. Every other time I usually reach 100% around 12noon if not sooner.

Having the power banks help me by ensuring I only draw down on my battery when it's already full. Although I typically would plug them in to charge up right as I went to bed around 10PM and by the time I woke up they be half charged up and my battery be liekly in the 90's if not 100% already.

My batteries are AGM I bought the Renogy boxed one where it has two 100ah inside the case. It's kinda sad, now that I live in an apartment again I know my system doesn't get the usage it should but when I do plan on moving citites being able to live out of my minvian until I start my job and have dependable income is an amazing asset and skill that is beyond useful in this modern age where rent is so damn high.

 

[DLTooley]

You can find the wattage of the rice cooker on the label, usually on the bottom. This is the maximum draw. From that you can estimate your total use. Just using the rice cooker when you are in the van will help to refine that use.

Induction electric cookers are the latest thing, I’ve looked at them but have not purchased. You do need an inverter for those. In any case you will likely need to upgrade your system. If you are driving daily into work a dc to dc charger can be a very useful recharge method in addition to solar.

At some point you will want to upgrade your batteries. LiFePo4 is an improving market, so waiting has benefits.

Propane is cheaper than butane, all the more so if you can find room for a common 20lb tank or the harder to find 10lb tanks. They do make duel butane/propane single burner stoves. $35 as I recall recently on Amazon.

I use my 12v fridge solely as a freezer and freeze ice jugs for use in a cheaper yeti style cooler.

There are a variety of portable panel options, also an evolving market. Given your usage a charging system from your vehicle might be the best next upgrade option. In any case you will likely find you want a backup stove anyways.

I only have a 600 watt inverter, there are induction electrics that can be set to that wattage. I have no idea how well that will work, so haven’t tried it yet.

 

[eDJ_]

Here are some 12 volt DC appliance suppliers:

Road Truckers

Sports Imports

RoadPro

 

[Tesota Overland]

This product from that Road Truckers site is a perfect illustration of why electric cooking in off-grid applications is very limiting:

https://www.roadtrucker.com/12-volt-appliance/roadpro-12-volt-20oz-smart-car-pot.htm

8A draw, 600mL capacity, 1 hour to boil water. For an 200Ah AGM setup you're looking at over 10% of your battery capacity just to heat some water. Might work if you're a trucker burning diesel all day every day, not so much if you need to charge off solar.

I've got a Travel Buddy and it almost works as a proper oven but the power draw is very high (the marketing says 10A but real-world it pulls more like 13-15A). Preheating to 300F+ takes 30-45 minutes if you need to actually cook something with it. Its alright for warming up rolls/bread or prepackaged frozen food but objectively speaking it is a terrible oven. I tried to make both brownies and biscuits in it, while they eventually cooked it took hours and flattened my batteries. These days I don't use it unless I'm driving and can afford the massive power draw. Having said all that, it's amazing to just toss something frozen in there and have a hot meal right when I get to camp with zero effort.

IMO battery capacity and tech is going to need to improve by an order of magnitude before electric cooking will be a truly viable option all around. Until then its going to be an exercise in managing expectations, if all you want is to warm stuff it'll be fine. If you're expecting to make thanksgiving dinner you will be disappointed. In that regard I think a rice cooker makes a good deal of sense - you're not trying to brown anything, they're generally well insulated and thermally efficient, and won't need to run for hours to make a meal.

 

[tx2sturgis]

In my experience the 12v lunchbox heaters (often called 'Burton Stoves' in the trucking industry) are fine IF you are driving for many hours AND surplus power is available from the vehicle's electric supply (alternator/battery). I would often use them for heating stew or soup or reheating the occasional frozen burrito. I wore out or broke or burned up a half dozen of them in a 40 year trucking career.

But as an off-grid camper with a few solar panels and a few batteries, they drain a LOT of reserve from your batteries and wont work well for very long.

 

[mikehosley]

I have about 400 watts of solar, and 100ah storage, and yet a large electrical load (such as cooking) will deplete it pretty fast.

You will be limited to morning 'opportunity' cooking, ie, only using it on sunny days when the sun has a chance of replacing what you are pulling out of the battery.

Keep in mind the typical 12v fridge/freezer uses all the energy a single 100 watt panel can produce over a 24 hour period (8-10 hours of sun exposure) during sunny weather and it will take 2 or more of the panels to break even in winter or on cloudy days.

If your cooking appliance of choice is drawing energy for any length of time from a marginal system after dark your system will quickly fall short of your goals.

Renogy power meter shows me consumption.
You can see how many minutes you have of power at your current level of consumption.
Microwaves, and heating elements consume 900 watts,

You can find the wattage of the rice cooker on the label, usually on the bottom. This is the maximum draw. From that you can estimate your total use. Just using the rice cooker when you are in the van will help to refine that use.

Induction electric cookers are the latest thing, I’ve looked at them but have not purchased. You do need an inverter for those. In any case you will likely need to upgrade your system. If you are driving daily into work a dc to dc charger can be a very useful recharge method in addition to solar.

At some point you will want to upgrade your batteries. LiFePo4 is an improving market, so waiting has benefits.

Propane is cheaper than butane, all the more so if you can find room for a common 20lb tank or the harder to find 10lb tanks. They do make duel butane/propane single burner stoves. $35 as I recall recently on Amazon.

I use my 12v fridge solely as a freezer and freeze ice jugs for use in a cheaper yeti style cooler.

There are a variety of portable panel options, also an evolving market. Given your usage a charging system from your vehicle might be the best next upgrade option. In any case you will likely find you want a backup stove anyways.

I only have a 600 watt inverter, there are induction electrics that can be set to that wattage. I have no idea how well that will work, so haven’t tried it yet.

Most of the induction cookers require 50 amps and they won't run on 600 W I have a 3000 watt inverter but I'm having trouble with the regular small induction electric cooker from Ikea it just doesn't work in the van although it works in the wall just fine

 

[StarryNights]

For 3 years I got by fine with 100AH @ 24v of lithium (same as 200AH @ 12v) and 400W of flat-mounted solar; never went below 60% SOC. I'm full electric, no propane, cook on Induction and have a large (130L) always-on 12v fridge plus the usual array of phones and laptop, all running on 12V. I occasionally use a 3qt Instant pot, usually to cook brown rice. For this, the pot must heat up to steam and then cook for 20 minutes. I carefully noted energy use: it used about 700 watts for 11 minutes to heat up and then draws nothing except for two 30 seconds bursts for the next 20 minutes while cooking. One could probably just turn the unit off once it reaches temperature and let it sit for 30 minutes and it would work and save a bit of energy (my inverter uses 50W at idle).

More info: Used mostly in AZ mid Dec to April. Inverter: 3,000 watt PSW with 9000w surge. Works fine with the 1500w induction cooktop and use it 2 or 3 times a day, but my cooking times are short. I have tested it running both the cooktop AND a 1500 watt space heater at the same time. No problem, but that is somewhat overkill; more capacity than most need.

 

[tx2sturgis]

Yes it can certainly work well for some, especially if they are careful and conservative, and (during winter season) hanging out in the southwest US.

If you have a surplus of energy production they you have a better chance, but the OP is seeing 77% by morning with the 200 watts and 200 ah battery bank, with mainly a fridge.

Obviously it also depends on where the OP plans to be in the winter, since there can be large differences in solar energy that can be harvested depending on location and weather patterns.

 

[magentawave]

I use a little non pressurized backpackers alcohol stove in my minivan conversion. Nowhere near the BTU’s of propane but space is at a premium here and it’s tiny and cheap and fuel stores safely in a quart size plastic soda bottle.

P.S. I don’t want to harsh your thing there, but if your rice cooker is aluminum then for health reasons you might want to avoid that.

 

[rruff]

8A draw, 600mL capacity, 1 hour to boil water. For an 200Ah AGM setup you're looking at over 10% of your battery capacity just to heat some water. Might work if you're a trucker burning diesel all day every day, not so much if you need to charge off solar.

When all you are doing is heating/cooking... use a fuel that burns. Solar electric is inefficient (expensive, lots of space) and unreliable (sun doesn't always shine).

 

[DLTooley]

Most of the induction cookers require 50 amps and they won't run on 600 W I have a 3000 watt inverter but I'm having trouble with the regular small induction electric cooker from Ikea it just doesn't work in the van although it works in the wall just fine

My research consists of Amazon searches. There are induction cookers which adjust by wattage, but I have not purchased or used.

With my 600 watt inverter I’d imagine that level would best be used for low and slow cooking, during good solar conditions.

 

[Ken in Anaheim]

Most of the induction cookers require 50 amps and they won't run on 600 W I have a 3000 watt inverter but I'm having trouble with the regular small induction electric cooker from Ikea it just doesn't work in the van although it works in the wall just fine

I believe an induction cooktop need a pure sine wave (PSW) inverter. Is that what you have ?