Faulty Electric Stove Thermostat

[Sarsippius]

Hi guys, I think there's a few electricians here from memory.
I moved into my new place a few months ago, I don't think the old tenant used the stove at all, the plates were rusted up a bit. Managed to clean them up ok but I think the thermostat is buggered because the large plate will get red hot on 1 and the smaller one never needs to go past about 3 to cook most things.
We've kind of lived with it but my first power bill was a bit higher than expected. It's the wet season here so the air-con is always on and the missus is here as well so overall usage will be up but it just got me wondering if the electric stove could also be sucking a bit more juice than normal. Any thoughts?
I'll probably bite the bullet and get some professional advice soon but thought I'd just ask here first.

[Santaria]

They're called Simmerstats and they sound like they need replacing (well, the large hotplate definitely). Stoves can suck a fair bit of juice, but not enough to go: "Holy shit, it went up THAT much?", Well, not unless you're using the hotplates as heaters.

Depending on the stove and the brand (any decent electrician can fit the unifits to just about anything) there's really only 2 types of simmerstat. One will set you back about $55, the other around $85.

[Sarsippius]

Thanks for the advice mate, I just kinda figured if the simmerstats aren't working right then the efficiency could be way down.
I'm in a virtually identical place to before so I can probably just chalk it up to the wifey being here now so more cooking on the stove compared to the microwave and an air-con on 24/7 rather than just when I'm home.