One of the best ways to save money on electricity around the home is when making hot water. Whether in the main hot water system for the home, or in boiling water for a cup of tea or coffee, there are many ways to save money on electricity.
For information on reducing electricity costs for the main hot water system in the home, refer to this Suite101 Article: Reduce Hot Water Losses in the Home.
Cheapest Way to Boil Water for a Cup of Tea or Coffee
When wanting to boil hot water to make a cup of coffee or tea, there are basically two ways this can be done using electricity.
- Boil the water in an electric kettle or electric jug; or
- Boil the water in a saucepan on the electric stove top.
The first method (electric jug or kettle) is the cheapest way to boil water to make that cup of coffee.
The author carried out some tests, with the following results for boiling two cups of water.
The kilowatt/hours result is the standard values that electricity suppliers use to charge for electricity consumption.
Power Used for Boiling Water in an Electric Jug or Kettle
For two cups of water to boil:
Time = 0.04 hours
Power demand = 2.193 kilowatts
Power used = 0.08 kilowatt/hours
Power Used for Boiling Water in a Saucepan on an Electric Stove Element
For two cups of water to boil in a saucepan:
Time = 0.14 hours
Power demand = 1.101 kilowatts
Power used = 0.16 kilowatt/hours
Comparing the Energy Used in Boiling Water in an Electric Kettle or on a Stove
Therefore, from these comparisons it can be seen that an electric kettle or jug is the optimum way to boil water.
An electric kettle uses around twice as much electricity as the electric element on the stove top; and this would seem to imply that the electric stove top option would be cheaper. However, the reason an electric kettle or jug is cheaper to boil water than the electric stove top is that the kettle will boil the water faster than the electric stove element, using less electricity overall.
One of the main reasons why the electric jug is cheaper is that the electric stove element option uses large amounts of power to first heat up the stove element, then transfer that heat to the saucepan and finally the water.
The electric kettle or jug has greater efficiency as the water is in direct contact with the electric element inside the kettle; making the heat transfer much faster.
Getting Optimum Electric Power Saving from an Electric Kettle or Jug
The above calculations and comparisons were for two cups of water. And, though this is acceptable for an experiment, in order to get the optimum savings on the electric power bill careful use of the electric kettle is needed.
When boiling water in an electric jug, only the water that is needed should be boiled. It is uneconomic to fill the electric kettle right to the top if only requiring a single cup of water. In this situation, well over eight cups of water (2 litres) would be heated to boiling point by the electric power.
The author is aware of an anecdote where an energy auditor visited a house to determine why an excess amount of electric power was being used. It wasn’t until the owner of the house offered the auditor a cup of coffee, and then filled the electric kettle to the top, that the reason for the large power bill was revealed. The house owner was continually boiling a full electric jug of water whenever they wanted a single cup, possibly ten or a dozen times a day.
Beside saving electric energy when making a cup of coffee, there are other ways to save money on the electricity bill from the electricity supplier that will impact the family budget, such as addressing heating costs around the home.
Bruce Iliff - Hello from an Australian freelancer! I’ve been scratching articles together in Australia in a range of subjects for a number of ...
Join the Conversation