A 30-watt bulb uses 0.03 kilowatt-hours every hour, or 30 kilowatt-hours in 1000 hours.
To find the kilowatt-hours, multiply 0.03 by the time in hours.
The idea is to divide the energy by the power used. First, convert the units to make them consistent. For example, you might convert kilowatt-hours to watt-hours.
A 200W light bulb will use 0.2 kWh (kilowatt-hour) of electricity per hour of operation. If the bulb is on for 5 hours, it would consume 1 kWh.
A 600 watt light bulb uses 0.6 kilowatts per hour. In 18 hours, it would use 10.8 kilowatt hours (0.6 kilowatts x 18 hours).
First let us convert the power of the bulb into kilowatts.A kilowatt is 1000 watts. We have one tenth of that. So 100W = 0.1kWTo work out the kilowatt hours we simply multiply the power in kilowatts by the time the bulb is on for (in hours):0.1kW x 10h = 1 kWha 100 watt bulb uses 100 watts of power. In ten hours it uses 100x10 watt-hours, or 1 kilowatt-hour. A kilowatt-hour is also called a unit, and units are what you pay for.
Energy-saving bulbs use much less than 1 kilowatt and most of them use less than 40 watts which is 0.04 kilowatts. A 20 watt bulb uses 1 kilowatt-hour of energy if run for 50 hours.
50 watts is 0.05 kilowatts, so in 24 hours it uses 0.05 x 24 kilowatt-hours, or 1.2 kilowatt-hours of energy.
Convert the 100 watts to kilowatts. Calculate the total time in hours, and multiply by the number of kilowatts that the light bulb uses.
The idea is to divide the energy by the power used. First, convert the units to make them consistent. For example, you might convert kilowatt-hours to watt-hours.
It depends on the bulb, how many watts it is. All bulbs are marked with the correct voltage and the power taken, in watts. You multiply the watts by the number of hours to find the watt-hours of energy used. Then divide by 1000 to find the kilowatt-hours. A kilowatt-hour is also called a unit and you pay about £0.15 for a unit of electricity. Let's say it's a 100 watt bulb running for 24 hours. That uses 2400 watt-hours or 2.4 kilowatt-hours, which costs about 2.4 x £0.15 which is £0.36.
A 200W light bulb will use 0.2 kWh (kilowatt-hour) of electricity per hour of operation. If the bulb is on for 5 hours, it would consume 1 kWh.
Add up all the individual watts, convert everything to kilowatts, then multiply by the number of hours.
A 600 watt light bulb uses 0.6 kilowatts per hour. In 18 hours, it would use 10.8 kilowatt hours (0.6 kilowatts x 18 hours).
First let us convert the power of the bulb into kilowatts.A kilowatt is 1000 watts. We have one tenth of that. So 100W = 0.1kWTo work out the kilowatt hours we simply multiply the power in kilowatts by the time the bulb is on for (in hours):0.1kW x 10h = 1 kWha 100 watt bulb uses 100 watts of power. In ten hours it uses 100x10 watt-hours, or 1 kilowatt-hour. A kilowatt-hour is also called a unit, and units are what you pay for.
1 kilowatt is equal to 1,000 watts, so a 100 watt bulb uses .1 kilowatt. Technically, your home or business meter base measures kilowatt hours, meaning that it measures both the kilowatts and the amount of time. If you turn on 10 100 watt bulbs for 1 second, that would be a kilowatt, but the amount of power use would be insignificant. So... To calculate the kilowatt hours: .1 kilowatts (from above, knowing the energy use of the bulb) Multiplied by 24 hours in a day Multiplied by 30 days... .1(kilowatts) * 24(hours)* 30(hours in a day) = 72 kilowatt hours
A kilowatt is 1,000 Watts. 30 Watts is equal to 0.03 kilowatts. A kWh or kilowatt-hour is the rate of electrical usage. It is a measure of kilowatts used per period of time (1 hour). 1 kWh is 1 kilowatt (1,000 watts) for 1 hour. So, multiply your 30 watts (0.03 kilowatts) by 1 hour to get kWh. =0.03 kWh In about 33 hours and 20 minutes, this lamp would use 1 kWh.
Energy-saving bulbs use much less than 1 kilowatt and most of them use less than 40 watts which is 0.04 kilowatts. A 20 watt bulb uses 1 kilowatt-hour of energy if run for 50 hours.
Takes 300 hours for the average light bulb to burn out