How would a $10.00 compact fluorescent light bulb (15 W) be an overall money saver compared to an incandescent light bulb (60 W) that costs $0.50?
To determine if the compact fluorescent light bulb (CFL) would be an overall money saver compared to an incandescent light bulb (ILB), we need to consider the purchase cost, energy consumption, and lifespan of each bulb.
1. Purchase Cost:
- The CFL costs $10.00.
- The ILB costs $0.50.
2. Energy Consumption:
- The CFL has a power rating of 15 W.
- The ILB has a power rating of 60 W.
3. Lifespan:
- The average lifespan of a CFL is around 10,000 hours.
- The average lifespan of an ILB is around 1,200 hours.
Now, let's calculate the energy costs and bulb replacement costs over a hypothetical period of 10,000 hours, assuming an average electricity rate of $0.12 per kilowatt-hour (kWh):
Energy Costs:
- CFL: In 10,000 hours, the CFL will consume 150 kWh (15 W * 10,000 hours / 1,000).
- ILB: In 10,000 hours, the ILB will consume 600 kWh (60 W * 10,000 hours / 1,000).
The energy cost for both bulbs:
- CFL: 150 kWh * $0.12/kWh = $18.00.
- ILB: 600 kWh * $0.12/kWh = $72.00.
Bulb Replacement Costs:
- CFL: Assuming a lifespan of 10,000 hours, no bulb replacements are needed.
- ILB: Since the ILB has an average lifespan of 1,200 hours, you would need to replace it approximately 8 times (10,000 hours / 1,200 hours).
The bulb replacement cost for the ILB:
- ILB: 8 replacements * $0.50 per bulb = $4.00.
Total Costs:
- CFL: $10.00 (purchase) + $18.00 (energy cost) = $28.00.
- ILB: $0.50 (purchase) + $72.00 (energy cost) + $4.00 (bulb replacement cost) = $76.50.
Comparing the total costs, the CFL ($28.00) is significantly cheaper than the ILB ($76.50) over the hypothetical period of 10,000 hours. Therefore, considering both the purchase cost, energy consumption, and lifespan, the CFL would be an overall money saver compared to the incandescent light bulb.