Cooking accounts for 5-6% of average electricity use.
Electric cooking can also be a major contributor to evening peak electricity demand. As electricity suppliers introduce time-of-use pricing or peak demand charges, it will be important to manage cooking demand. Gas prices are also increasing.
The way you heat up (or defrost) food can also affect energy use, as does the way you manage cooking post the ‘heating up’ phase.
The appliances themselves (such as ovens, grillers etc) all have their own efficiencies and optimal usage patterns.
What to look for when buying
- Fan-forced, double- or triple-glazed and well-insulated ovens are most efficient
- Induction cooktops are about 25–30% more energy-efficient than standard electric, and 30% more efficient than gas
- Electric ovens are roughly twice as energy-efficient as gas ovens
Consider portable induction cooktops if you’re a tenant or can’t afford a permanent one. See section on Induction Cooktops below.
- Defrost food prior by using a microwave or placing it in the fridge’s fresh food compartment
- Reheat food with a microwave
- Check/replace damaged oven door seals
- Don’t pre-heat unnecessarily
- Keep lids on pots and simmer gently, rather than boiling rapidly. Minimise the amount of water “boiled off” as evaporating water is very energy intensive. A lid traps heat, making the most of the energy flow and cutting down on the time needed to cook
- Cook meals in bulk and then freeze
- Microwaves, electric frypans or pressure cookers are much more energy efficient than using the oven
- Consider investing in a thermal cooker, used in conjunction with your cooktop but allowing you to save up to 80% on cooking energy usage
- If possible, plan to cook several dishes in your oven at once
- Keep the oven door closed as much as possible. Every time the oven door is opened, the oven temperature drops by 14-20ºC
- Clean range hood filters regularly
- In extreme weather the overuse of a range hood can significantly increase heating/cooling energy use as it sucks outdoor air into the apartment to replace the air it removes
- Use an electric kettle instead of the electric stovetop to boil water
- Fill the kettle with only as much water as you need. Consider using a thermos, if you enjoy a lot of hot drinks, to save reheating the water
- Toasting in a toaster or sandwich maker instead of the grill reduces energy use by up to 75%
Over a year, a microwave will generally use more power to keep its clock running than it does in actually cooking food.
Many coffee machines have high standby consumption, as they often keep water hot in uninsulated tanks or heat components for long periods in case you want another coffee. Choice magazine found some that use up to 30W on standby and other research has estimated up to 340 kWh/year if left on all the time – more than an efficient fridge! (Source: ReNew magazine, Issue 130, Energy Efficient Cooking.)
Induction cooktops work by creating a magnetic field that induces an electric current in the pot, thus heating it. Heating the base of the pot directly in this way conserves energy compared to when heat is transferred via an element or flame to the pot and then the food.
Induction cooktops are over 80 per cent efficient (by comparison, conventional electric is around 60 per cent, and gas only 35 to 40 per cent).
Induction cooktops heat up fast, with changes in temperature occurring instantaneously.
They require ferromagnetic cookware (e.g. cast iron or some stainless steels). Take a magnet along when shopping. If it’s attracted, it will work with induction cookers. Test the whole base surface to ensure it is entirely compatible and don’t trust labels alone, as the ferromagnetic material could be limited in area and result in patchy heating.
Induction cooktops need a higher amperage electrical connection, depending on their size. This is something to double-check. We’ve heard of people who can’t get enough power to their apartment.
(Source: Sanctuary Magazine, Issue 30, Induction cooktops – now we’re cooking!)
Portable induction cooktops
They’re relatively inexpensive, and easy to move around if you’re a tenant – and the perfect solution if you’re stuck with inefficient built--in cooktops. Here’s what one couple did in their apartment – a simple shelf over an old electric cooktop for two portable induction units.