Energy usage of new oven vs old?

waqasahmed

I don't need to change my oven just yet and I won't realistically change it until it stops working

If you've had to replace your oven in the past few months, have you noticed any significant energy reduction with the new one vs the old? 

macman

Assuming you are talking about an electric oven, why would there by any difference? All electrical devices have the same efficiency (100%), so a 3kW oven is going to use the same power in an hour (3kWh) if running full on whether it's old or brand new.
The only possible difference between different models would be the insulation. 

Swipe

Oven chips in my conventional 2KW oven on the top shelf take 30 mins (without preheating) and in my 1.5KW JML halogen oven on the wire stand take just 12 mins.

Scot_39

macman said:

Assuming you are talking about an electric oven, why would there by any difference? All electrical devices have the same efficiency (100%), so a 3kW oven is going to use the same power in an hour (3kWh) if running full on whether it's old or brand new.
The only possible difference between different models would be the insulation. 

Metal mass to heat, convection/fan assist modes, additional leakage / seal issues as age etc could all play a part.

It's an interesting question re age of oven as for some things - or sizes of things for larger families - conventional ovens are still almost an essential. 

But sorry don't know.

And options depends if talking electric oven - as far cheaper gas makes it more difficult to save by the common all electric alternates still. And the new July cap sees its price advantage bounce back a little too - electric currently c3x, nearer 4x come July, per kWh.

But many - as post ex above - have moved to likes of air fryers - so much so shelves were emptied of certain brands lower priced models last autumn etc - or halogen, combi or slow cookers to save - where suitable.

My 20yr+ Bosch electric c2kW main oven takes 15-20mins to preheat to 200 no fan mode, more like 10-15 with fan to 170/180 to cook same thing where suitable.  I though that was normal - but others tell me thats quite slow.

I can cook some things in my air fryer - lower peak power used mark space in less total time - than takes oven to preheat.

Its now for many more a question of what sort of device - or combination to use - than just what efficiency of main oven.

As I say probably far more of an issue for all electric than those with mains gas / gas oven.

And in winter - remember any theoeretical excess heat used to cook - contributes to overall home heating - so not truly wasted - unless all vented outside via window or fan hood etc.

One of my regulars - 2 simple crispy baked potatoes - 5  min microwave, oil and season, blast for 7-8 min air fryer - as I like that nice crispy skin taste - vs typically maybe 1hr+ in conventional after 15-20min preheat to get same result.  Yes I know could do even faster cheaper just in microwave. 

That time saving a double boost to me when start to cook late - to save at my e10 off peak rate - that starts 8pm in winter.

waqasahmed

Scot_39 said:

macman said:

Assuming you are talking about an electric oven, why would there by any difference? All electrical devices have the same efficiency (100%), so a 3kW oven is going to use the same power in an hour (3kWh) if running full on whether it's old or brand new.
The only possible difference between different models would be the insulation. 

Metal mass to heat, convection/fan assist modes, additional leakage / seal issues as age etc could all play a part.

It's an interesting question re age of oven as for some things - or sizes of things for larger families - conventional ovens are still almost an essential. 

But sorry don't know.

And options depends if talking electric oven - as far cheaper gas makes it more difficult to save by the common all electric alternates still. And the new July cap sees its price advantage bounce back a little too - electric currently c3x, nearer 4x come July, per kWh.

But many - as post ex above - have moved to likes of air fryers - so much so shelves were emptied of certain brands lower priced models last autumn etc - or halogen, combi or slow cookers to save - where suitable.

My 20yr+ Bosch electric c2kW main oven takes 15-20mins to preheat to 200 no fan mode, more like 10-15 with fan to 170/180 to cook same thing where suitable.  I though that was normal - but others tell me thats quite slow.

I can cook some things in my air fryer - lower peak power used mark space in less total time - than takes oven to preheat.

Its now for many more a question of what sort of device - or combination to use - than just what efficiency of main oven.

As I say probably far more of an issue for all electric than those with mains gas / gas oven.

And in winter - remember any theoeretical excess heat used to cook - contributes to overall home heating - so not truly wasted - unless all vented outside via window or fan hood etc.

One of my regulars - 2 simple crispy baked potatoes - 5  min microwave, oil and season, blast for 7-8 min air fryer - as I like that nice crispy skin taste - vs typically maybe 1hr+ in conventional after 15-20min preheat to get same result.  Yes I know could do even faster cheaper just in microwave. 

That time saving a double boost to me when start to cook late - to save at my e10 off peak rate - that starts 8pm in winter.

This is essence what I was getting at in terms of things that could be improved and have been 

I'm currently on Octopus tracker myself, due to move to flux once I get more panels on. I got very close to 15p/kWh just a couple of days ago

But, yes I wouldn't change for the sake of it but just generally curious 

markin

If the door seals are in good working order, then i think its likely just down to a fan or not, i don't think anyone is going to install Aerogel

Scot_39

I don't know about specifics - Just looking at one big box retail park seller - their built in electric ovens range from B to A++ for efficiency and quote data for a standard cycle under some 65/2014 measure.

For instance taking an A and an A++ rated device - although slightly different volumes -

the more efficient one A++ claims 0.52 kWh use per standard "cycle" in fan mode

- it's non fan mode a more expensive 1.09 kWh. Thats over Double

the 2 cheapest - A rated - 079/0.8kWh - thats over half more.

One 1l smaller, the other 5l smaller, are fan ovens - but only quote one figure - so only assuming that's the fan mode - as more than the A++ fan mode - but less than the A++ conventional.

And taking a sample B class - curiously all dual ovens - an even higher 0.96kW - assuming that's the c60l bigger of the two.

The one gas I checked had an even higher 1.68 kWh on it's energy rating label - but that still had an A rating.

But given gas currently a third of the price on SVT (10.3 vs 32.8 ave iirc) and soon to be a quarter (7.5 vs 29 iirc in July) - costs comparable and soon to be better - than even the best electric.

Use the oven a couple of times a day - some folk do - I guess that adds up - although not in the bad vs good heating league - it is a year round expense.