Heat Output of my Stove

Since we’re shopping for a new stove, and one feature I find attractive is a higher output burner (particularly for stir-frying), it occurred to me to check what the heat output of my existing big burner is.

Stand Back, I’m Going to do Science

Our Ancient Magic Chef Stove

My burner, on high, raised 64 fluid ounces of tap water (measured in a single large Pyrex measure) from 67°F to 130°F (by my new Taylor instant-read cooking thermometer; scale is 2 degree intervals, so the 67 is interpolated by eye) in 4 minutes (by my Casio stopwatch). I pre-heated the pan slightly, the water sizzled when I poured it in. This both accounts somewhat for the mass of the grate and the pan needing to be heated, and eliminates the need for three hands to turn on the burner, start the stopwatch, and pour in the water simultaneously.

Bowl of Plenty says I can ignore the difference between distilled water and tap water, and that water weighs 2.0803 pounds per quart.   (Yeah, “a pint’s a pound” is off by .04015 in modern measurements.)

Stove burners are rated in BTUs/hour, which they usually just call “BTUs”.  Reading between the lines, they’re rated by the theoretical heat production of the volume of gas they handle. Actual heat production depends on combustion efficiency. Then there’s heat transfer to the cooking vessel. Then, in my experiment, there’s heat loss to radiation, air convection, and water evaporation. I make no attempt to account for those. Reading various online articles,  people seem to think heating measured the way I did it will be about 1/2 the BTU rating of the burner.

The BTU was traditionally defined as the energy needed to raise one pound of water by 1°F at atmospheric pressure (which is about 1055 joules). (There are BTU definitions at different temperatures, which give slightly different results.)

So, 2 quarts × 2.0803 pounds/quart × ( 130 – 67) degrees = 262.1178 BTUs.  4 minutes is 1/15 of an hour, so that’s 3,932 BTUs/hour. (Yeah, I carried all the meaningless digits through to the end and then rounded.)

The rumored 2x efficiency factor from rating to reality would mean that my burner would rate a bit under 8,000 BTUs/hr.

Normal burners of modern stoves rate 8,000–12,000 BTUs/hour, so that passes sanity check.

And it also suggests that a modern stove with a burner rated at 17,000 BTUs/hr would be a LOT better for stir-frying, or for cooking pasta for that matter.

I would have felt really stupid buying a new stove with a spiffy keen high-output burner, only to discover it produced less heat than my old burner did.

So, do ya think this might have been easier in metric units?  (I could have done it that way, just translating the temperatures I measured, and then translating the BTU ratings of the new stoves back to metric. But once I got done researching the definition of BTU and the density of water, it seemed like more fun to use them directly.)

Also, this is yet another example of a practical math and science problem people can encounter around their home.

Vegan Pancakes II

2C white flour
2T sugar
2T baking powder
1/4t salt
2 1/4 C unsweetened soy milk
5T vegetable oil

Basically, I cut down the baking powder and increased the soy milk and vegetable oil.

The result was less cardboardy, but still not supple, and they were too thick still.  Pamela and Lydy agreed they were as thick as last time, despite more liquid and less baking powder.

I’m also rediscovering why I hate gas stoves so much; getting the two-burner griddle to be both fairly uniform and the right temperature (especially since the front and back burners have different size gas rings) is hell, and the only thing one can really adjust based on is the visible size of the flames.

These things were sticking to an oiled non-stick griddle until I turned it up a bit.

The Smuckers boysenberry syrup is okay, but nothing special. Has more “berry” quality than specific boysenberry flavor.


Finally started taking action on the problem of not getting enough pancakes in my life.  As it turned out, this required a last-minute trip to the store, since the amount of soy milk in the house was inadequate.

I did a batch of vegan whole-wheat pancakes that were okay (better than today’s batch, as I remember it) a long time ago, but don’t seem to have said anything or recorded the recipe.

Last two pancakes in the batch

I don’t like “fluffy” pancakes.  I like something closer to crêpes.

The recipe as I made it today:

1 cup white flour
1T sugar
1.5T baking powder
1/8t salt
1C unsweetened soy milk
2T vegetable oil

Mix, cook on medium hot  griddle, probably greased.  Makes 2 servings.

These came out kind of okay, though a bit thick, a bit tough, and a bit flavorless (I thought they lacked salt).

For next time, I plan to add something like 1/8 cup soy milk, and take the baking powder down to 1T.  (The original recipe actually called for 2T, I reduced it before making this batch.)

Turns out baking powder has huge amounts of sodium in it, when used in this kind of quantity.  Today’s recipe had 42% of the allowable sodium intake for a normal diet.

In the long run I’ll play with grains, I think, and maybe play with vegan egg-replacer.  I’m looking for a more rubbery, less cardboard, kind of a texture.  More oil might be involved too.  I’m trying to limit the number of things I change at once for a few iterations; though I suppose I may eventually give up this recipe entirely.

I could give up the vegan route, and work  on normal pancakes.  But that leaves Pamela out, which seems like it shouldn’t be my first choice.