To calculate the cost of a traditional incandescent bulb versus an LED bulb, we need to consider factors such as the initial purchase price, energy consumption, and lifespan. Let's break down the calculation:
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Initial Purchase Price:
- Traditional Incandescent Bulb: Let's assume the cost of a 60-watt incandescent bulb is $1.
- LED Bulb: The cost of a comparable 10-watt LED bulb is $5.
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Energy Consumption:
- Assume the average usage of the bulb is 4 hours per day.
- Electricity Cost: $0.12 per kilowatt-hour (average residential rate).
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Lifespan:
- Traditional Incandescent Bulb: Lifespan of around 1,000 hours.
- LED Bulb: Lifespan of around 25,000 hours.
Now, let's calculate the total cost over a span of 5 years (assuming continuous usage for simplicity):
Traditional Incandescent Bulb:
- Energy Consumption per day: (60 watts / 1000) * 4 hours = 0.24 kWh
- Energy Consumption per year: 0.24 kWh * 365 days = 87.6 kWh
- Energy Cost per year: 87.6 kWh * $0.12/kWh = $10.51
- Total Energy Cost for 5 years: $10.51 * 5 years = $52.55
- Bulb Replacement Cost (assuming 5 replacements over 5 years): $1 * 5 = $5
- Total Cost (Energy + Bulbs): $52.55 + $5 = $57.55
LED Bulb:
- Energy Consumption per day: (10 watts / 1000) * 4 hours = 0.04 kWh
- Energy Consumption per year: 0.04 kWh * 365 days = 14.6 kWh
- Energy Cost per year: 14.6 kWh * $0.12/kWh = $1.75
- Total Energy Cost for 5 years: $1.75 * 5 years = $8.75
- Bulb Replacement Cost (no replacements needed over 5 years): $0
- Total Cost (Energy + Bulbs): $8.75 + $5 = $13.75
In this simplified example, over a 5-year period, the total cost of using a traditional incandescent bulb would be approximately $57.55, while the total cost of using an LED bulb would be only $13.75. This calculation clearly demonstrates the long-term cost savings associated with LED bulbs due to their lower energy consumption and longer lifespan.