Our kitchens are a major source of carbon emissions and energy waste. Even without factoring in the carbon or energy footprint of the foods we eat, kitchen energy use accounts for about 15% of a home’s total energy use — and by some estimates, up to 20%. Whether you’re building a new zero energy home or wanting to upgrade your existing kitchen, there are several steps you can take on the path to zero carbon cooking. The most important is to choose the most highly energy-efficient equipment for the task. That is the foundation for making other important choices regarding food selection, preparation, and waste that can also lower the carbon footprint of your kitchen.

 

More Efficient, Quicker, and Better than Gas Stovetops

Induction stovetops cook about 50% faster than gas, offer better control, use much less energy than gas — and use a bit less than standard electric coil stovetops. For quick cooking, close to 90% of energy goes to the food in the pan, while gas transfers about 38% of its energy to the food, and standard electric transfers 65 to 70%. For longer cooking, electric coil heating is almost as efficient as induction; while both are much more efficient than gas. With induction, the stovetop barely gets warm, so you clean up spills as they occur; and they are safer for children than either standard electric or gas stovetops. Electric cooking also improves indoor air quality. Cooks appreciate the cooking speed and better control of temperature provided by induction. Listen to why professional chefs love induction stoves.

 

Another Advance in Energy-Efficient Cooking Makes Cooking Easier

The Instant Pot saves up to 70% of electricity used compared to cooking with a saucepan, steamer, or large pot on a standard stove top — or compared to standard oven cooking. It cooks quickly at high temperature and pressure, reducing cooking time by 70%, similar to other pressure cookers. However, it is better insulated than standard pressure cookers — with two layers of trapped air between the inner cooking pot and the outside. It’s cool to the touch when cooking something quick, and it’s lukewarm when cooking for longer times. Its smart monitoring system only heats the inner pot sufficiently to maintain the needed pressure level, so that when you are cooking for longer periods of time, the heating is off nearly 40% of the time. It uses less water during cooking — as much as 75% less, which contributes to the reduced energy use; and it does not overheat the kitchen during hot weather.

 

Some people use the Instant Pot for almost all their cooking. It can be used reliably for soups, stews, pot roasts, stir frying, and sauteing. It excels at cooking whole grains and beans. And it can be used for baking bread, cookies, and cakes, although they do not turn out crispy. The bottom line is that it can be used for a wide variety of dishes with very low energy use.

 

More Efficient Ovens

Large ovens are great for baking and broiling large items, but they are energy inefficient because of their size. There are some energy-saving alternatives to baking and broiling in a large oven. Many kitchen ranges come with a second smaller oven that will often suffice. And many standard ovens now have convection settings, which cook quicker and more evenly and therefore use less energy. Self-cleaning ovens are better insulated than regular ovens and are therefore more efficient.

However, size matters. Countertop ovens or “toaster ovens” are sized right for many small cooking tasks and use about ⅓  to ½ less energy than a large oven. They have been notoriously poorly insulated and energy inefficient, so look for one that produces the least surface heat — a sign that they are better insulated.

 

Use Your Microwave

For basic cooking and heating functions that do not involve broiling, a microwave oven is two or three times more efficient than most standard ovens. Cooking in a standard electric oven is about 12 to 14% efficient, in a gas oven 6 to 7% efficient, and in a microwave oven 56% efficient. Cooking, thawing, pre-cooking, or reheating small portions of food in the microwave may save close to 80 percent of the energy that would be used to cook or warm them up in the oven. For those who are adventurous, a surprising number of dishes can actually be baked in the microwave using very little energy, although there are a few jobs not well suited to microwaves. For example, it is more efficient to use an induction stovetop than a microwave to heat water for coffee or tea. Baking breads, cookies, and cakes may best be done in a smaller standard oven or energy-efficient toaster oven.

 

Refrigerator and Freezer Energy

Purchase an ENERGY STAR refrigerator and freezer when equipping a new home or replacing older appliances. Look for the most efficient models in each category. Depending on your household size, consider buying the smallest refrigerator that will work for your situation. Even if they are more “efficient,” a 28 cubic foot model will still use more than a model that’s 22 cubic feet. Refrigerators with the lowest energy use are usually 16 to 20 cubic feet. Locate your fridge in a cool place (not next to the stove or dishwasher) with plenty of air circulation (at least one inch), beside and behind the fridge. Look for a refrigerator with an energy-saving switch, and, if you can, go without the ice maker dispenser, which uses 14 to 20% more energy than making ice in ice trays. Look for a chest freezer, as they are 10 to 25% more efficient than upright freezers.

 

What About Kitchen Cleanup

Another source of energy use in kitchens occurs during cleanup. Hot water and dishwashers use a good deal of energy. Be sure to look for the most energy efficient ENERGY STAR dishwasher model.

For hot water, be sure to include a heat pump water heater in new home specs or when replacing an existing one, as they are considerably more energy-efficient than standard water heaters. However they require a room with 100 cubic feet of space, louvered doors offering good airflow, or supplemental ducting for tight spaces. If you have to stick with a conventional electric water heater, purchase a well insulated model and add several more solar collectors to cover the energy used to heat the water — energy modeling can help determine the extra cost for this option.

Another part of kitchen cleanup is getting rid of cooking odors and excess heat. That is where the microwave oven, the Instant Pot, and the induction stovetop can save big. No gas fumes, great control over cooking temperatures, and less waste heat. Using an advanced ventilation system found in most zero homes expels any remaining cooking odors and smoke.

 

Kitchen Lighting

People who cook frequently use more lighting in the kitchen than in other rooms of the house, so it’s a great place to use LED light bulbs. Switch out specialized halogen lights, which are high energy users commonly found in kitchens. Use natural light and focused task lighting where possible and turn out the lights when leaving the kitchen.

 

The Big Picture

Operating the typical kitchen represents a concentration of home energy use, greenhouse gas emissions, and threats to indoor air quality. Fortunately, there are energy-efficient, air quality friendly options for every function in the kitchen. When designing or retrofitting to zero with a low carbon kitchen you can improve your indoor air quality, reduce your home’s energy needs, and reduce the amount of solar panels needed, to get to zero. In a zero energy ready home, a low carbon kitchen will improve your home’s energy performance by bringing down its HERS rating and increase your savings on energy bills.

Designing a new home or remodeling is the perfect opportunity to get started on the right foot with a full array of highly efficient appliances and water heating options. For existing homes, the perfect time to upgrade efficiency is when an old appliance needs replacing. Whatever your situation, there’s a clear path to a low carbon kitchen.