not a great selection, poll-wise. its either you preheat all the time because you ignorantly do what your mom tells you to do, or you only do it for baking when it's necessary.

i preheat a lot, because i bake bread/pastries.

but in other cases, i preheat as well. like when i'm moving a braise from the stovetop to the oven, i want a hot oven. otherwise the whole thing cools off again before it starts actually cooking in the oven. or when i'm putting something delicate in the oven to finish cooking after i sear it in a pan, i want the oven to be hot.

I preheat most of the time. However, I don't let my oven languish for a half an hour while I wait to make sure it's up to temperature. Modern ovens don't need nearly that long to get up to temperature. I wait about 5 minutes at the most and let many of my foods "coast" towards the end of cooking. I'd like to add that I have found preheating the oven and the pan indispensable when it comes to roasting potatoes ( I live for the sizzle).

Another way to save energy is to do bake several dishes in a row. I like to make a casserole and get a loaf of bread ready while it is cooking, that way one dish preheats for the next.
When doing without preheating remember that you need to add some baking time to your recipe 5-20 minutes depending on the destination temperature.
One more energy saving trick: when cooking pasta, boil the water, dump in the pasta and let it boil for 30 sec while stirring to prevent sticking, then turn the stove off and let the pasta cook in the hot water till done. It usually takes only a couple of minutes longer than boiling for the full time and the pasta comes out exactly the same.

Some people have to pre-heat the oven... our oven automatically goes through a pre-heating cycle before you can use the timer. You cannot stop the pre-heat cycle. It is a Whirlpool glass-top stove/oven with electronic controlls.

I got tired of reading speculation, so I did an experiment. I have a TED energy monitor, so I could measure the energy consumption of my electric oven. From a cold start (60 F), to 350 F, it took 10 minutes (almost exactly) and used 0.4 kWh. I then opened the door wide and slow and closed it again, to simulate putting something in, and measured energy consumption for the next 10 minutes. The heater kicked in for a bit after the door opening, and again for a bit at about the 7 minute mark, but the cumulative consumption was only 0.1 kWh. The resolution on the meter is only 0.1 kWh, so that doesn't tell me very precisely what it was, but the conclusion is clear: Warming up the oven in the first place takes the bulk of the energy, and that happens whether you preheat or not. Once it's heated up, maintaining the temperature for an extra 10 minutes, as will happen if you preheat for 10 minutes, takes some energy, but it's relatively minor.

So Michael's suggestion of baking a bunch of things while you've got it heated up is much more important that whether or not you pre-heat.

If you are wondering about the TED energy monitor, it's at http://www.theenergydetective.com/

My current oven heats nice and fast, so I only need to preheat for baking. But I used to rent a condo where the oven was terrible. It heated very slowly, and that one I would preheat every time, just starting it up as I got ingredients out. Otherwise it was adding 15 and more minutes to the cooking time, which was really frustrating.

I preheat most of the time.

I always pre-heat my solar oven. I don't see a problem. I'm using a totally clean, renewable energy source so it doesn't matter if I waste energy by preheating - whether it's 100, 400 or 1000 watts worth of energy waste.

Thanks to Michael for the pasta tip. I will be trying it next time I make some to see how it turns out.

I'm in Korea where ovens are quite uncommon, so at the moment I don't use one at all.

Back in Texas we had a wood burning oven for baking bread, pizzas, potatoes, etc. So that we did have to preheat ;)

I've always pre-heated, but I'm willing to try skipping it (maybe not for baking though).

For most of our baking or broiling I use our toaster oven, and I preheat it. We can fit a full-size pie in our toaster oven, and it's just right for six cookies at a time, which is all we want for a late-night treat.

When I need to cook in the main oven, which is very rarely I preheat it. I keep a piece of unglazed tile in it so that opening the door doesn't lose a ton of heat. Also, my oven beeps when it's at the proper temperature, which means I'm not letting it sit there empty and hot.

My next range will be a gas range because I cannot stand electric ranges. I know that I can't get natural gas from the sun or wind, but I will not tolerate a range that doesn't turn off completely when I turn it off. I can't tell you how many dishes I've burned because I forgot that "Off" isn't actually off on an electric range.

It will probably also have a convection oven, which cooks things much faster than a conventional oven and saves energy.

What about savings by turning your oven off prematurely?

Also, where are you getting these numbers? What about the difference between natural gas, propane, or electric stoves? Are you talking about pounds of Carbon Dioxide, or pounds of greenhouse gasses? Is that pounds per hour, or pounds per minute? Is that at 400F or 350F?

Your link for these numbers leads to a private company that states those numbers without any mention of proof. Shame on you treehugger.

I'm crying foul on this article.

LA: it's just a survey, and I Iink back to three sites, not stating my position on any of them. Shame on me for what?

Timing is key. If you pre-heat your oven and let it bake nothing for 20 minutes, then there is a lot of opportunity to reduce energy. But if the oven reaches it's temperature as you are ready to put your goodies in, not so bad.

Using heavy gauged glass, iron or stone bakeware lets you get away w/o pre-heating, and you can coast through the end. It just takes a a little practice.

I always turn off the tea pot before it whistles, and the heat in the element always finishes the job. Same with pasta, bring to a boil and let it coast...