If you were only looking to use half the number of lights (8.2′ instead of 16.4′), then divide this number in half. 24W * 3.5 hours = 84Wh per day. What is the energy consumption in watt-hour when the power consumption is 5 watts for time duration of 3 hours? Electricity bill calculation Energy consumption calculation. This means 1 Wh is the amount of energy used by something operating at 1 W for an hour, and 60 Wh is the amount of energy something would use … A 100 watt light bulb uses 100 watts of power. We use that and multiply it by how many hours a day we think the lights will be on. watt-hour = watts × hours. To convert the power in watts to kilowatt-hours, multiply 100 watts by 1 hour, then divide by 1,000 to find the energy usage in kWh. Watts to kWh calculation How to convert Wh to watts Energy = (100 × 1) ÷ 1,000 Energy = 100 ÷ 1,000 Energy = 0.1 kWh. Our energy calculator allows you to calculate the running cost of any electrical items using a range of electricity tariffs. The energy E in kilowatt-hours (kWh) is equal to the power P in watts (W), times the time period t in hours (hr) divided by 1000: E (kWh) = P (W) × t (hr) / 1000 . E = 5W × 3h = 15 Wh . 12 * 3.5 hours = 42Wh per day The energy E in watt-hour (Wh) is equal to the power P in watts (W), times the time period t in hours (h): E (Wh) = P (W) × t (h) So. Wh = W × h. Example. or. Electricity Cost Calculator. It is a handy tool that helps you understand how much energy is stored in the battery that your smartphone or a drone runs on. LED light strips can be cut to size. In a way similar to amp-hours, a watt-hour (Wh) is the amount of energy used when something operates at a given number of watts for a certain number of hours. The energy E in kilowatt-hours (kWh) per day is equal to the power P in watts (W) times number of usage hours per day t divided by 1000 watts per kilowatt: E (kWh/day) = P (W) × t (h/day) / 1000 (W/kW) Electricity cost calculation kWh to watts calculator Watts to kWh calculation. If electricity costs \$0.12 per kWh, then a 100 watt light bulb will cost 1.2 cents per hour that it’s on. Simply enter the amount of electricity the appliance uses (in Watts or KiloWatts) and the length of time it is used (in Hours … Watts to watt-hour calculation formula. If you want to convert between amp hours and watt-hours or find the C-rate of a battery, give this battery capacity calculator a try. So, if a light bulb uses 60 watts, it requires 60 joules of energy per second.