Reducing oven pre-heat to temp time

[SickThings]

Would putting a few bricks in the bottom of my oven reduce the time it takes to heat to cooking temperature by reducing the amount of space that needs heated? Would this also reduce the amount of power consumed during the cooking process, due to the fact that the bricks would retain the heat? Are there any reasons not to try this?

My oven is usually less than 25% full when cooking something. Looking for ways to reduce the pre-heating time and save money.

[boxtops]

I don't know. Bricks retain heat, certainly, since my old storage heaters used to be full of bricks. Wouldn't it take longer in the first place, though, to heat up the bricks to the required temperature?

[SickThings]

Not sure about that boxtops. I assumed it would take a shorter time because the smaller amount of air in the oven would heat to temp before the bricks, and the thermostat would kick in by measuring the air temp.

[buildersmate]

Unfortunately the reverse is true.
Bricks take a heck of a lot of energy to heat them up per unit volume - hundreds of times more than air. That's why they are used in storage radiators - because once they've taken all that energy in, they have a lot to give back out again.
Whilst it is true that heating air does require energy, and some of that energy gets lost when you open the door and the hot air escapes, this is chicken-feed compared to the brick effect. That is why a circulating air oven is designed to stop the fan instantly when one opens the door - to try and minimise the amount of hot air getting out.
The best way to try and save energy are to make sure the door seal is in good condition. Insulating the oven box with fibreglass would also help, but I wouldn't try it - too difficult.

[snags]

''Would putting a few bricks in the bottom of my oven''

My Mum spent years doing this... and serving them up under the guise of Dinner...

[wildwood]

Perhaps one of those small plugin benchtop ovens would be ideal for you.

[bushbaby_de]

get a microwave that is also an oven and grill

[AlBags]

It would heat the oven interior air quicker to temp ...
BUT the element would be on longer to also heat up the added bricks (as they would absorb heat)
If you use it several times a day, yes .. but use firebricks.
I use a Mini Convection Fan Oven. Ready to 200degC in 5 mins.
The less you heat, the more economical it should be.

[ruthie]

My new Bosch oven has instructions for cooking food starting from a cold oven! I haven't tried it yet and I'm not sure that it would work. I've had the oven for less than a week so there's plenty of time yet to prove or disprove this. I'll let you know if I'm brave enough to cook something in the oven from cold.

[ethandron]

unless it's crucial to the proper cooking of something (like baking) i always put food into the oven as i switch it on - meat, roast veg, etc. - and it comes out great. you just have to reduce the cooking time a bit, again, that's not a problem for most things.
baking cakes, pastry, bread, etc., is different though and always needs a preheated oven.