# Boiling eggs on an electric or gas stove: why the boiling time difference?

Having fairly recently moved from a country where cooking on gas is the standard (the Netherlands) to a country where cooking electrically is the standard (Sweden), I've noticed that I need to boil my eggs a good minute, minute and a half longer than I used to.
I always put them in as the water is already boiling.

Until now my assumption has been: boiling point is boiling point–once the water hits 100°C the heat dispersion goes up rapidly, keeping the temperature close to that–but it appears my assumption was false.

Anyone care to explain?

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Are the eggs the same size? Are you using the same size pot and same amount of water? – Harlan Nov 27 '10 at 23:15
@Harlan: Triple yes. – oKtosiTe Nov 28 '10 at 0:43
Are the eggs starting at the same temperature they were? The stove isn't the only new appliance! And is it a full rolling boil, so you can guarantee the water gets well-mixed to a constant temperature? – Jefromi Nov 28 '10 at 1:56
Now that you mention it... my girlfriend–with whom I moved here–prefers to store the eggs in the fridge. In the Netherlands I usually stored them in a cupboard. How I could miss such an elementary observation is beyond me. :-) – oKtosiTe Nov 28 '10 at 16:00
A full rolling boil indeed. – oKtosiTe Nov 28 '10 at 16:01

Is there a difference in altitude between where you live now and where you used to live? The heat of a gas and an electric stove should be the same, but boiling temperature differs. The higher the altitude, the lower the boiling point, since it's a factor of air pressure. (More explanations from Wikipedia.)

Water only boils at 100C at sea level. This site can calculate it for you.

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Good point! Although I can't measure the difference very accurately myself, it can't be more than 30 meters higher at my new location. – oKtosiTe Nov 28 '10 at 0:38
This was my first guess too. According to that link, Amsterdam's elevation (2m) gives you an extra degree C of temp compared to Stockholm. – Mr. Shiny and New 安宇 Nov 28 '10 at 3:13

Silly, silly me.

As Jefromi suggested earlier, the largest contributor to the fact it takes that much longer is probably the fact that the eggs are at a different themselves at the moment I put them in. I used to store eggs in a cupboard; now I store them in the refrigerator.

That is not to say the other factors mentioned by Martha and Sklivvz don't add to that–they most likely do–but this seems the most reasonable, if unanticipated, explanation.

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It's probably due to the fact that gas stoves heat up the water continuously, whereas electric stoves turn on and off.

Since you put in the eggs after the water is boiling, they make the water go below the boiling point, but the gas stove starts instantaneously to heat up the water again, and the electric stove may or may not.

To test this hypothesis: put in the eggs with cold water and count 9 minutes after the water starts to boil. Of course, you also need a gas stove... ;-)

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Sounds reasonable. I do believe, however, that this is much more the case with a glass top stove than with a coil stove (which is what I use now). As it easily takes fifteen minutes for the coils to cool down, I'm not sure the argument holds. – oKtosiTe Nov 28 '10 at 15:55
Sadly I don't have a gas stove to compare; I don't even know anyone here who owns one. I will keep it in the back of my head in case that changes, and hopefully post back with my findings. – oKtosiTe Nov 28 '10 at 16:03

When I make hard boiled eggs, I always use the oven. This way, you can preheat to the exact temperature and they always cook the same. What I usually do is place the eggs on the racks, and put something underneath in the unfortunate case one of them breaks. I know not every ovens are the same, but this should allow for a more controlled environment. Also, I have fit between 50 and 60 eggs in my oven at the same time, which is great for parties.

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