Managing energy usage

[trkarl]

Most of us store dried things like beans and rice for long term storage. Cooking usually involves boiling and simmering which can consume large amounts of energy. So I did a little experiment with cooking some dried black beans.

In a grid down scenario electricity would be a scarce commodity. Some of us like myself have off grid renewable production capability but would need to manage it wisely to get the most accomplished for the least amount used. I wanted to see how much electricity would be used cooking black beans in various ways.

I took one cup of dried black beans and soaked them for 6 hrs in each experiment before cooking. They were then cooked in 4 cups of room temp water to start according to directions for each method.

These are the tools used to cook them:



A Kuhn Rikon Duromatic 6 litre pressure cooker

A Vollrath 59500P Mirage Pro Countertop Induction Range 1800 watt

A General Electric hot plate 1000 watt

Kill-a-watt meter to measure total kwhs.

Here are the results:

1) Beans soaked 6 hrs then cooked in 4 cups water in the pressure cooker for 12 min using the induction cook top. Energy used .25 kwh

2) Beans soaked 6 hrs then cooked in 4 cups water in the pressure cooker for 12 min using the hot plate. Energy used .30 kwh

3) Beans soaked 6 hrs then cooked in 4 cups water in the pressure cooker NOT under pressure. Brought to a boil then simmered for 2 hrs. using the hot plate. Energy used .97 kwh

4) Beans soaked 6 hrs then cooked in 4 cups water in the pressure cooker NOT under pressure.
Brought to a boil then simmered for 2 hrs. using the induction cook top. Energy used .80 kwh

Results were pretty interesting. Using induction capable cookware and an induction cook top where the cooking method was the same in each instance consumed about 20% less electricity.

There was no contest between pressure cooking and the standard boil/simmer. Boil/simmer with a hotplate used about 400% more energy than pressure/induction did.

On a side note I just got the induction cook top a couple months ago. These things are amazing. You can go from a cold pan with some butter in it to done scrambled eggs in around 2 minutes.

[Bearman202]

A friend checked into something like this and found that the absolute cheapest way to cook beans was to soak them, bring them to a boil, then put them into a straw box (?) and leave them there for a long time, i.e. 6 to 8 hours. The box held in the heat, and they cooked. He was out the amount of energy it took to bring them to a boil.

[1Admin]

Great thread, 5 stars! How old were the beans?

[monkeybird]

http://theinductionsite.com/proandcon.shtml

I know absolutely nothing about induction cooking. So I did a quick google search. I was surprised to learn you had to have special cookware. How expensive is the cookware required for this method?

Also, induction cooking equipment is expensive compared to their energy hog cousins. Below is just a link to one at the Home Depot. Other brands are even more expensive. If I remember from the first time I saw an induction cooking oven, my jar dropped at the price - so I believe the price has come down.

http://www.homedepot.com/Appliances-...atalogId=10053

So, if you purchase an induction cooking system, how much less electricity will you use?

I wonder about a solar oven? Has anyone cooked something like beans in one?

[dilli]

soaked beans in a well positioned solar oven will be done by dinner time. If i am worried about them not cooking in time i will either bring them to a rapid boil and let sit the evening before or soak and heat my water to boiling before putting them in the solar oven. of course, in my eyes nothing beats cooking them over a slow burnin woodstove or outdoor fire. A small pressure cooker really speeds the process up over those two methods as well. We have noticed after being fossil fuel free with cooking now for a few years that there are many days that one needs to have a slow fire burning to cook other things or accomplish other chores so beans over fire isnt that big of a deal , especially in a pressure cooker.

[trkarl]

How old were the beans?

They are around 1 yr old. No special packaging just left in the bag in my storage room.

@ monketbird. The cookware just needs to be able to have a magnet stick to the bottom of it. It works through magnetism. The equipment is expensive. Also I found out the cheaper units have only 4 inch elements to heat with so this could cause uneven cooking in a pan with a larger bottom. Mine is a commercial unit. It has an 8 inch element. As far as energy efficiency goes it uses around 20% less than a typical cook top. Also since it only heats the bottom of the pan there is very little heat radiated around the unit itself which heats up the kitchen raising your cooling costs. The unit itself does not heat up. Only the bottom of the pan. One thing they warn about is not to set metal utensils right next to the pan while cooking or it could heat up.

@ dilli. Yeah the pressure cooker is really the way to go. Especially since most preps are centered around dried beans and rice. When fuel like propane or nat gas is in short supply you want to get the most out of it and letting a pot simmer for hours is just a waste. Renewables like wood or solar or wind and hydro gives you a big jump towards self sufficiency especially if fuel is not able to be had for a long time.

I realize there are other ways of cooking without electricity but for most new "preppers" the first thing they get is a generator. The purpose of this experiment was to show the huge power requirement difference between cooking methods. Kinda like the difference between the microwave and the oven. Time also plays a factor. It would suck running that 5 kw genny for 2 + hrs just to cook your beans when it only would take a total of about 15 minutes in a pressure cooker.

[Knobster]

Very cool info. Never thought about a pressure cooker for cooking dried foods... Thanks!

[Klayton]

The pressure cooker is the king of speed, it is what the Colonel used to start off his Fried Chicken Franchise (in case you guys didn't know that already)... :)