An energy-efficient lightbulb, taking in 26.0 W of power, can produce the same l

Question

An energy-efficient lightbulb, taking in 26.0 W of power, can produce the same level of brightness as a conventional lightbulb operating at power 100 W. The lifetime of the energy-efficient bulb is 10 000 h and its purchase price is $4.60, whereas the conventional bulb has lifetime 750 h and costs $0.54 per bulb. Determine the total savings obtained by using one energy-efficient bulb over its lifetime as opposed to using conventional bulbs over the same time period. Assume an energy cost of $0.20 per kilowatt-hour.

Explanation / Answer

Energy Bulb specs

1. Wattage 26 W

2.Lifetime : 10000 h

3. Cost : $4.6

Conventional bulb

1. Wattage 100 W

2.Lifetime : 750 h

3. Cost : $0.54

Let us see how many bulbs are required for 10000 h

i.e 10000/750 = 13.3 = 14 bulbs

Cost of 14 bulbs = 14 x $0.54 = $7.56

Savings on number of bulbs = $7.56 -$4.6= $2.96

Savings on electricity

Savings on one second = 100-26 = 74 Watts

Savings for one hour = 74 x 3600 Watt hour =266.4 Kwh

Savings for 10000 hours = 266.4 x 104 Kwh

Savings per Kwh = $0.2

Savings on 1000 hours =$ 53.28 x 104

Total Savings = $ 53.28 x 104 + $2.96

Related Questions

Navigate

• Browse (All)
• Browse A
• Subjects

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.