The cost of powering an electrical device is determined by its energy consumption over a period and the price you pay for electricity. This calculator helps you estimate the monthly cost of running any appliance or device.
How it Works:
The calculation involves several steps:
Calculate Daily Energy Consumption (Watt-hours):
This is found by multiplying the device's wattage by the number of hours it's used per day.
Daily Watt-hours = Device Wattage (W) × Hours Used Per Day
Calculate Monthly Energy Consumption (Watt-hours):
We then multiply the daily consumption by the number of days the device is used per month.
Monthly Watt-hours = Daily Watt-hours × Days Used Per Month
Convert to Kilowatt-hours (kWh):
Electricity is typically billed in kilowatt-hours (kWh). To convert watt-hours to kilowatt-hours, we divide by 1000.
Monthly kWh = Monthly Watt-hours / 1000
Calculate Monthly Cost:
Finally, we multiply the total monthly kWh consumption by the cost per kWh.
Monthly Cost = Monthly kWh × Cost Per Kilowatt-Hour ($)
Example:
Let's say you have a 150W television that you use for 5 hours a day, 25 days a month, and your electricity rate is $0.12 per kWh.
Daily Watt-hours = 150W × 5 hours = 750 Wh
Monthly Watt-hours = 750 Wh × 25 days = 18,750 Wh
Monthly kWh = 18,750 Wh / 1000 = 18.75 kWh
Monthly Cost = 18.75 kWh × $0.12/kWh = $2.25
This calculator provides a useful estimate for budgeting and understanding your electricity usage.
function calculatePowerCost() {
var deviceWattage = parseFloat(document.getElementById("deviceWattage").value);
var hoursPerDay = parseFloat(document.getElementById("hoursPerDay").value);
var daysPerMonth = parseFloat(document.getElementById("daysPerMonth").value);
var kwhCost = parseFloat(document.getElementById("kwhCost").value);
var resultValueElement = document.getElementById("result-value");
if (isNaN(deviceWattage) || isNaN(hoursPerDay) || isNaN(daysPerMonth) || isNaN(kwhCost) ||
deviceWattage < 0 || hoursPerDay < 0 || daysPerMonth < 0 || kwhCost < 0) {
resultValueElement.textContent = "Invalid input";
return;
}
var dailyWattHours = deviceWattage * hoursPerDay;
var monthlyWattHours = dailyWattHours * daysPerMonth;
var monthlyKwh = monthlyWattHours / 1000;
var monthlyCost = monthlyKwh * kwhCost;
resultValueElement.textContent = "$" + monthlyCost.toFixed(2);
}