There is no Energy Star Rating for ovens, ranges, or microwaves at this time and, with the exception of commercial ovens, I don't think there is any plan for rating these items in the near future.
- Since the carbon emissions from cooking are relatively low (4.5% of the energy we use at home according to the U.S. Department of Energy), Energy Star doesn't have this on their high priority list.
- Still, I, like you, would prefer to cook as energy efficiently as possible.
Because the heat is instant with gas, gas is considered more efficient than electric. For this reason, when electric is what you are saddled with, electric induction heat is the way to go. Its response time is the same as gas and it stops instantly when it is turned off.
About induction, Wikipedia says:
"In induction cooking, a coil of copper wire is placed underneath the cooking pot. An alternating electric current flows through the coil, which produces an oscillating magnetic field. This field induces an electric current in the pot. Current flowing in the metal pot produces resistive heating which heats the food. While the current is large, it is produced by a low voltage... Because the surface of the cook top is only heated from contact with the vessel, the possibility of burn injury is significantly less than with other methods. The induction effect does not heat the air around the vessel, resulting in further energy efficiencies. Cooling air is blown through the electronics but emerges only a little warmer than ambient temperature."
So forget the saying "If you can't stand the heat, get out of the kitchen."
The interesting thing here is that it is like the process skips a step -- instead of turning energy first to heat and then heating the cooking vessel, the energy is supplied directly to the cooking vessel by the magnetic field. Since your hand are not ferromagnetic, you don't get burned. (OK, junior might not learn hot from cold the classic way by touching the stove with this one, but that has its pluses too.)
- You might have to buy a new pot made of ferromagnetic metal (stainless or cast iron, not aluminum or copper) or at least an interface disk, but it is definitely the way to go with electric.
- Plus induction stoves look cool because you just see a nice glass top for a stove.
- Before induction, good cooks all preferred gas, but not only can induction be as instant as gas but also as powerful and as precise. You can even get that super low simmer for that big pot of chili. Concerning chili, my only complaint is that I can't char the peppers by throwing them on the gas stove top but you can do that in the oven.
The following appliance companies make induction appliances. I have had good luck with them in general, although I don't claim to be up on their latest induction equipment: Miele, Wolf, Gaggenau, Kenmore, GE, and Thermador.
There are lots more, I'd check Consumer Reports and other sources for the latest data.