1. You often have to pre-heat the oven, so during that time, you are not cooking food
2. The oven is rarely full, so instead of heating food, you are heating the oven
3. The oven remains hot after the food is removed, but you could argue that's low-grade heat, unsuitable for cooking
If my electric oven is just 12% efficient, I'd like to know why (and how I can get one that is more efficient). I understand that microwave ovens are much more efficient (I guess because the heat is generated inside the food). But they're no good for browning food, or baking bread.
I'm still lost on this notion that an electric oven is just 12% efficient. If that's true, then I could patent a device that harvests energy from electric ovens, and make a mint.
My oven, on full power, draws 2KW (at least, that's what the labels on my fuze-box suggest). If only 12% of that energy is used to heat the food, then the oven amounts to a 200W food cooker, combined with an 1800W electric heater (I rounded down to 10% to make the reckoning easier).
I live in a studio flat; my oven is in my living room. How come I can survive without A/C? But I seem to be able to roast and bake without my home warming up.
My microwave is an old cheap one, with a max. power of 700W. Assuming that's 100% efficient, then it should cook food about 3.5 times faster than the inefficient oven, I guess; and it does. So it does seem that the oven is inefficient. But why? Where is the lost energy going?
Most of the energy created by the oven doesn't actually go into the food, it heats up the air which heats up your food (and also the walls of the oven). While a microwave pretty much only heats the water molecules in your food.
To roast a chicken to 165f you'll probably set your oven to 400f. And then when it's done, the air and interior of your oven are still very hot. When you microwave food, you can touch the side-walls of your microwave right away and they won't be hot. The only excess heat in a microwave comes from the food steaming and contact with the platter.
I suppose:
1. You often have to pre-heat the oven, so during that time, you are not cooking food
2. The oven is rarely full, so instead of heating food, you are heating the oven
3. The oven remains hot after the food is removed, but you could argue that's low-grade heat, unsuitable for cooking
If my electric oven is just 12% efficient, I'd like to know why (and how I can get one that is more efficient). I understand that microwave ovens are much more efficient (I guess because the heat is generated inside the food). But they're no good for browning food, or baking bread.
I'm still lost on this notion that an electric oven is just 12% efficient. If that's true, then I could patent a device that harvests energy from electric ovens, and make a mint.