Have a look under your stove tops drip trays, on my stove its below the left rear elements drip tray. It is a steel vent tube 2" in diameter that joins the inside of the oven to under the elements , A direct Vent. Have a look at your oven roof , you will notice a vent / hole.
My number is purely a guess , I do not care to test it , it works good enough.
The hole is tin foil capped from the top , its a easy reach under the element tray.
I notice a lot of heat was heating the back of the stove top when using the oven and while cleaning the trays I plugged the vent hole. The stove top no longer turns into a burn hazard , keeping the heat inside instead of 24/7 venting all the heat from the moment you try to heat the oven all the way threw the cooking process.
Anyone could test heat up time and on off cycle duration with & without the vent covered and see what savings there is.
I feel confident in my guess
edit: Electric household oven stove , I know the common oven stove combo's have the vent tube.