Cooking food from smaller solar power systems has always been one of my key interests. High tech survival and emergency preparedness too.
But cooking with standard kitchen appliances often seems out of reach due to the high power draw required. And many people do not have large batteries and inverters to do the task.
The Bare Minimum Setup
What is a bare minimum setup for a solar powered emergency cooking kitchen? I was recently contacted by a LiFePo4 battery company called Dr. Prepare. They sent me 2 of their 12-volt 20 amp-hour (LiFePo4 / Lithium Iron Phosphate) lithium ion batteries to test and review. This seemed like a good time to look into the idea and answer the question.
I did not think 2 small batteries would be able to do much cooking at all. My thought was to start with the smallest AC 120v cooktop I owned. If the 20ah batteries could run that cooktop, I figured there was a chance of the setup being useful.
For the inverter I chose my standard 12v 1000w pure sine wave unit. To charge the batteries, I had a 100 watt solar panel and a 20 amp MPPT charge controller on hand.
All of this equipment was cobbled together in a great hurry – emergency conditions. However in general emergency preparedness it’s important to know your equipment and what it’s limitations are beforehand.
Cooking Tests
the ultimate workout
I took the 20ah LiFePo4 batteries into the kitchen after charging, so they did not have any assistance from the sun and were not charging during the test. I set up my inverter with the batteries and plugged in the cooktop.
It actually turned on, but exceeded the power rating of the 2x 20ah batteries by about 18%. Normally this is a bad idea. However, in an emergency, one might not have a choice.
Anyway the pan heated up eventually, so we started by scrambling an egg. This didn’t take very long, the batteries survived so we went on to make some toast. And then we cooked some apples.
Voltage dropped to around 12.3 volts under load, this is definitely evidence of the very high amp draw (C-rate) versus relatively small amp-hour capacity.
But that wasn’t enough, so we then ran a coffee percolator (this takes a long time, well over 15-20 minutes or more). Long story short, the batteries did everything I asked, even while getting a little warm. And they still had capacity left over.
My Thoughts
I have a lot of experience trying to cook off of small solar power setups. But I never tried a compact setup setup exactly like this. The cooktop I had was a known “power hog” and seemed a bit out of reach.
However with lithium ion batteries, it’s possible to output larger amounts of current in a “burst” without risking them too much. The number one concern is cell heating. Not suprisingly these batteries did get a bit warm, but nothing disasterous. Add to that fact the cooktop was cycling on and off, therefore allowing brief periods of cooldown.
Small Off-Grid Solar Power Systems Can Cook Food
The take home message here is even with a relatively small system, it’s possible to run a small scale emergency kitchen using small kitchen appliances. With the assistance of one or two 100 watt solar panels, the scenario looks even better. During extended emergencies, morale is important. Hot drinks, hot food and even hot water can make all the difference in the world.
Lots of folks don’t have anything like this setup at home for emergencies. A couple hundred bucks for batteries, an inverter and a solar panel can save the day and set them free from cooking fuel constraints. My desire is to make people aware of what even a small off grid solar power setup can do, even those who are not interested in solar power at all.
Emergency preparedness is a good investment for everyone, not just solar power enthusiasts.
Dr. Prepare 20AH LiFePo4 Test
I would like to thank Dr. Prepare http://www.drprepare.com for providing the 2x 20AH LiFePo4 sample batteries included in the test and review. In my opinion, after a short term review they work like they should and even exceeded my expectations.
Note: I don’t get paid for any sales; these are my own opinions. The link to the product I tested is here https://drprepare.com/12v-20ah-lifepo4-lithium-deep-cycle-battery-10-year-warranty/
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