Hello there, I'm a specialist in energy efficiency and cost analysis. I'm here to help you understand the cost of running a 100-watt light bulb for 24 hours straight.

First, let's break down the information provided and analyze it. The statement suggests that an incandescent light bulb costs about 50 cents and lasts approximately 750 hours. It also mentions that running a 100-watt bulb for 24 hours a day would result in an annual usage of 876 kilowatt-hours (kWh). The cost of electricity is given as about 15 cents per kilowatt-hour.

Now, let's calculate the cost of running a 100-watt light bulb for 24 hours a day for a year:


1. Calculating Annual Energy Consumption:
- The bulb is 100 watts, or 0.1 kilowatts (kW).
- It runs for 24 hours a day, so in a day, it consumes \( 0.1 \text{ kW} \times 24 \text{ hours} = 2.4 \text{ kWh} \).
- Over a year (365 days), it would consume \( 2.4 \text{ kWh/day} \times 365 \text{ days/year} = 876 \text{ kWh/year} \).


2. Calculating Annual Cost of Electricity:
- If the cost of electricity is 15 cents per kWh, then the annual cost would be \( 876 \text{ kWh/year} \times 0.15 \text{ USD/kWh} = 131.40 \text{ USD/year} \).


3. Considering the Lifespan of the Bulb:
- The bulb lasts about 750 hours. If it runs for 24 hours a day, it would last approximately \( 750 \text{ hours} / 24 \text{ hours/day} \approx 31.25 \text{ days} \).
- Over a year, you would need to replace the bulb about \( 365 \text{ days/year} / 31.25 \text{ days/bulb} \approx 11.68 \text{ bulbs/year} \).
- The cost of replacing the bulbs in a year would be \( 11.68 \text{ bulbs/year} \times 0.50 \text{ USD/bulb} \approx 5.84 \text{ USD/year} \).


4. Total Annual Cost:
- Adding the cost of electricity and the cost of replacing the bulbs gives us the total annual cost: \( 131.40 \text{ USD/year} + 5.84 \text{ USD/year} \approx 137.24 \text{ USD/year} \).

It's important to note that these calculations are based on the provided information and may not reflect the actual costs in different regions due to varying electricity rates and bulb prices. Additionally, the lifespan of a bulb can vary depending on usage patterns and environmental factors.

Moreover, incandescent bulbs are among the least energy-efficient lighting options available. There are more energy-efficient alternatives such as compact fluorescent lamps (CFLs), light-emitting diodes (LEDs), and others that could significantly reduce both energy consumption and costs.

In conclusion, running a 100-watt incandescent light bulb for 24 hours a day for a year would cost approximately 137.24 USD, considering both the electricity cost and the cost of replacing the bulb. However, this is a simplified analysis and actual costs may vary.

read more >>

An incandescent light bulb costs about 50 cents and lasts about 750 hours. If you were to leave a 100-watt bulb burning for 24 hours each day, 365 days per year, it would use 876 kilowatt hours per year. ( 1000 watts equals one kilowatt -C --kilo-- means a thousand.) A kilowatt-hour of electricity costs about 15 cents.read more >>