Appliance power and the electricity bill sim
Switch on a kettle, toaster, fan and LED lamp, set a timer, run them and watch an energy meter count kilowatt-hours, then record each run and work out the cost at a price per kWh you choose.
Practical electricity: power, energy and cost · covers the O-Level, IGCSE, GCSE topic
What the sim shows
Mains electricity in Singapore and the UK is an AC supply; 230 V is its usual working value. An appliance's power is P = VI, so the current it draws is I = P ÷ V: the 2000 W kettle draws 8.70 A. The energy it transfers is E = Pt = VIt. Electricity companies measure energy in kilowatt-hours: energy in kWh = power in kW × time in hours, and 1 kWh = 1000 W × 3600 s = 3.6 million joules. The cost is the energy in kWh × the price per kWh. The power ratings are typical values from appliance rating plates (kettle 2000 W, toaster 1000 W, desk fan 45 W, LED lamp 10 W). The price per kWh is an example that you set; it is not a real tariff. Each appliance is taken to draw its full power all the time it is on; a real kettle switches itself off when the water boils. In the kettle and toaster, a heating element (a resistance wire) transfers electrical energy to thermal energy.
- Rocker switches: click to turn each appliance on or off
- Timer dial: drag it to set the hours; then run for that time
- Energy meter: power now, and a kWh counter that adds up the energy
Use it in your lessons
- Try it here: anyone can unlock 2 figures free, and a free account unlocks up to 5. Runs on a laptop, a Chromebook or a phone; nothing to install.
- Present it and share student links with the teacher plan, from US$5 a month, billed yearly.
- Put it on your own website or LMS for US$9, paid once, or every sim from US$29 a month.
Free guide: 12 practicals as sims, and how to run one in a lesson →
Need a version for your exact set-up? Have one made: US$49 a figure in an order of 5.
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