Posted by Charley Cormany, EFCA Executive Director
For years, professional chefs have touted the benefits of natural gas stovetops for cooking. Gas burns clean, burners heat up instantly, and temperature is easy to regulate. High-end kitchens have been combining gas cooktops with electric ovens for years.
Lately, though, a plethora of studies and news stories have warned us that cooking with natural gas is dangerous.
I have managed several kitchen remodeling projects where the designer specified a “chef’s kitchen, ” including a gas cooktop and electric oven. Now I question if installing the gas cooktop was the right solution.
Gas ovens are designed to heat up past the setpoint, shut off, reduce the flame, and kick back on when the temperature drops. Because they constantly chase the setpoint, they can’t maintain even cooking temperatures as well as their electric counterparts. New technology has improved this, but electric ovens are usually preferred for baking because they regulate their output effectively and maintain constant temperatures.
When it comes to cooktops though, many people still believe precise flame adjustment and heat output makes gas superior to electric. Gas burners are simple devices and have not evolved much over the years.
Older electric cooktops use resistance coil burners – the curly things that glow red hot. More modern ceramic electric cooktops use a flat surface with resistance heating or halogen elements. The flat surface makes them easy to clean and a lot better looking. They heat up faster and offer better performance than electric resistance coils.
To really compete with gas burners on efficiency and effectiveness though, you need to look at electric induction burners.
Indoor Cooking and Indoor Air Quality
Before we get to induction stoves, let’s talk about the many problems of gas. “Clean Natural Gas” has a nice ring to it – just like the marketing experts intended. It’s too bad none of it is true.
Building science professionals have long been aware of the impacts of combustion appliances in homes. Combustion safety testing is required any time you change the building envelope. The push for tighter and better-insulated homes increases the risk from combustion appliances.
One of the most dangerous pollutants from combustion appliances, carbon monoxide, is a colorless, odorless gas. At low levels, carbon monoxide leaks cause symptoms in people similar to a common cold. At higher levels, CO poisoning is fatal. Carbon monoxide is a silent killer.
I have done combustion safety testing on hundreds of homes. A part of this process involves testing each burner and the oven (if gas) to measure their carbon monoxide (CO) levels. If the levels are too high, the appliance may need service. If the levels are excessive, the home gets red-tagged and can’t be occupied until the situation is resolved.
How often do building performance specialists find CO issues with gas cooking appliances? In short, all the time. The worst culprit is gas ovens.
Sometimes the issue is as simple as a dirty burner. Other times it might be due to a broken or defective part. New appliances can have problems too. One of the worst cases of CO I have dealt with was in a house with a brand new $6k gas range. It turns out the unit was damaged during shipping. There was no external evidence of the damage.
After several weeks of using her brand new range, the homeowner connected the headaches she and her children were experiencing to her prepping dinner while the kids did homework at the kitchen table. The levels of CO we measured in the house were several times the safe limits established by the Environmental Protection Agency (EPA).
Install carbon monoxide detectors in your home. They may save your life. Something else to consider, if you live in an all-electric home, there are no combustion appliances, which mitigates all of these risks.
Use Your Range Hood!
In addition to installing carbon monoxide detectors, the most important takeaway I can give you from this article is to use your range hood when cooking, especially when using gas.
We all have range hoods over our cooktops. Unfortunately, most people don’t use them properly or understand why they are necessary. Many people think the range hood is there to remove steam when heating water. Evacuating excess water from home is a good idea, but a range hood’s primary function is to remove the combustion byproducts created when cooking.
Cooking with an open flame produces combustion byproducts. Even with “clean natural gas,” the combustion process is never 100 percent complete. Combustion byproducts- nitrous oxides, carbon monoxide, PM2.5 particulates, and others – tend to be rather nasty and harmful to your health. If these names sound familiar, it’s because they are the same byproducts emitted from the tailpipe of a car or truck.
Any time you use a gas cooktop, you need to turn on your range hood unless you like filling your home with toxic byproducts. I doubt you would ever consider backing your car up to your house and pointing the tailpipe at an open window. Cooking with gas without proper ventilation is effectively the same thing. To make things worse, most residential range hoods, even on high, can’t get rid of all combustion byproducts.
Recent Studies Are Changing Perceptions
As the pandemic has forced so many of us to spend more time indoors, people have started paying more attention to indoor air quality.
Several recent studies on the impact of cooking indoors have stirred things up. Several years ago, researchers at the Lawrence Berkeley National Laboratory (LBNL) conducted a survey evaluating the effectiveness of range hoods. The conclusion, people don’t use their hoods, and even when they do, they are not as effective as we believe.
In 2020, the Rocky Mountain Institute (RMI) and the UCLA Fielding School of Public Health published reports concluding that cooking with natural gas impacts indoor air quality much more than anticipated. On many occasions, the pollution levels inside the homes exceeded EPA recommendations for outdoors.
During the Covid lockdowns, Harvard researchers conducted a study on elevated PM 2.5 levels and death rates from Covid-19. They found significant evidence that high PM 2.5 levels generated from cooking with natural gas increased mortality rates. Small, long-term increases in PM 2.5 levels increased death rates from Covid by as much as 15 percent!
A recent American Chemical Society found that a majority of gas appliances leak natural gas. Even worse is that 75 percent of the emissions happened when the device was off. Imagine that you have a device in your home that adds pollutants to the air you breathe when it is off!
Not Your Mom’s Electric Cooktop
Unlike gas or electric resistance, electric induction cooktops heat the pan, not the burner. They do this by using magnetic energy to excite molecules in the pan to create heat.
Induction cooktops are a game-changer. They heat up fast, maintain temperature effectively, and are easy to clean. Today’s induction cooktops heat up faster than gas and have more precise temperature controls, eliminating the performance argument for cooking with gas. Another bonus: because induction cooktops don’t rely on a hot surface to heat the pan, they are safer than electric resistance or gas.
Most importantly, induction cooktops do not rely on fire to create heat, which means they do not produce harmful combustion byproducts.
Induction cooking has won over many top chefs, including Wolfgang Puck and Thomas Keller. The only real drawback to induction cooking is the cookware must have ferrous material (iron) for the magnetic forces to work. If you want to check your cookware, it’s simple. If a magnet sticks to your pan, you are fine. Most new cookware also has labels on the bottom to indicate what types of heat sources are compatible.
If you have reservations, I encourage you to buy a small single burner induction hot plate and test it out. We recently purchased one for my daughter to use in her dorm room. We tested it out first, and it is impressive. It was cheap, just over $50, and you plug it into a standard 110v outlet.
We Have Options
To quote Amory Lovins, it’s time to “Reinvent Fire.” The first time I heard that quote, I didn’t get it. Today it makes total sense.
For years people have believed that cooking with gas was the best solution. Today we know that induction stovetops and electric ovens can easily replace gas cooking in our homes.
These solutions are not a compromise; they are an improvement. Induction cooking is safer and more efficient than natural gas. Induction cooking uses less energy than electric resistance cooking. Electric appliances don’t produce combustion byproducts, and electricity does not leak into the atmosphere and contribute to climate change.
The future of residential energy will be electricity from carbon-free sources. I think life is full of risks. Adding dangerous pollution levels to your indoor environment is one you can easily mitigate. Perhaps it’s time you consider your energy sources for indoor cooking.