# 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?

• Are the eggs the same size? Are you using the same size pot and same amount of water? Commented Nov 27, 2010 at 23:15
• @Harlan: Triple yes. Commented Nov 28, 2010 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?
– Cascabel
Commented Nov 28, 2010 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. :-) Commented Nov 28, 2010 at 16:00
• A full rolling boil indeed. Commented Nov 28, 2010 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.

• 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. Commented Nov 28, 2010 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. Commented Nov 28, 2010 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.