How electricity cost is calculated
Electricity is billed in units (kilowatt-hours, kWh). For each appliance: units/month = watts × hours per day × days ÷ 1000, then cost = units × your rate. A 1500 W air conditioner running 8 hours a day for 30 days uses 1500 × 8 × 30 ÷ 1000 = 360 units — often the single biggest line on a bill.
Typical appliance wattages
- Air conditioner: 1000–2000 W · Water heater/geyser: 1500–3000 W · Electric heater: 1000–2000 W
- Iron: 1000–1800 W · Microwave: 800–1200 W · Water pump: 750–1500 W
- Refrigerator: 100–250 W · Washing machine: 400–1300 W · Desktop PC: 150–300 W
- Ceiling fan: 60–80 W · TV (LED): 60–120 W · LED bulb: 7–15 W · Laptop: 40–80 W
How to lower your bill
- Attack the biggest line first — usually AC, heater or geyser. Even 1 hour less a day adds up fast (change the hours and watch).
- Set AC to 26°C, use fans alongside, and service filters — each cuts consumption.
- Swap old bulbs for LED and switch off standby loads.
Where do I find my rate?
It's on your electricity bill, often as "rate per unit" or price per kWh. Many places use tiered slabs — use your average or the slab you fall into.
Is this exact?
It's a solid estimate. Real bills also include fixed charges, taxes and slab tariffs, so treat this as your usage cost — great for comparing appliances and cutting waste.
What uses the most power?
Anything that makes heat or cold: air conditioners, heaters, geysers and irons. Lights and fans are usually tiny by comparison.