Whether a gas kettle is cheaper than an Electric Kettle depends mainly on two factors: the price of energy in your area and the efficiency of the appliance. In many places, gas costs less per unit of energy than electricity, which can make boiling water on a gas stove slightly cheaper.
Experiments comparing the cost of boiling water show that gas can sometimes be cheaper for small quantities. For example, one comparison found that boiling one cup of water cost about 0.5p using gas compared with around 1.4p using an electric kettle.
However, this difference depends on local energy prices and how much water is heated.
Even though gas can cost less per unit of energy, Electric Kettles are usually more energy-efficient. Electric Kettles heat water directly using an internal heating element, which reduces heat loss. Many electric kettles reach efficiency levels around 80%, while stovetop heating often loses more heat to the surrounding air.
Electric kettles also tend to boil water faster than gas kettles. In tests, electric kettles can bring water to a boil in about 1–2 minutes, while gas stoves may take several minutes longer depending on the burner size.
Gas kettle: Usually cheaper per use in many regions because gas energy costs less.
Electric kettle: More efficient and faster, but electricity may cost more depending on the local energy price.
In practice, the cost difference per cup of tea is usually very small, often only a few cents per use, so many people choose based on convenience rather than cost.