A 20kW rated motor has an average loading of 75% of rated power and has an...

Free

90.2K

Verified Solution

Question

Finance

A 20kW rated motor has an average loading of 75% of rated powerand has an efficiency of 80%. The motor has a peak loading of 100%of rated power. The motor operates 1000 hours a year. The cost ofelectricity is $0.10/kWh and $7/kW-month of demand. Assume themotor operates at periods of peak demand at the facility (i.e. themotor power impacts the billing demand). An energy efficiencyupgrade reduces the average power consumed to an average loading of50% of rated power and reduces the peak power to 75% of ratedpower, but increases the operating hours to 1500 hours per year.There is no change in the efficiency of the motor after theupgrade. The cost of the energy efficiency project is $10,000. Whatis the annual electricity cost of running the motor before andafter the energy efficiency upgrade? What is the simple payback ofthe project?

Answer & Explanation Solved by verified expert

4.4 Ratings (572 Votes)


Before Energy Efficiency upgrade
Peak Loading =75% of rated power=	20KW
Effeciency	80%
Power needed =20/0.8=	25	KW
Number of hours in a year	1000
Annual power consumption =25*1000	25000	KWh
Cost of electricity =25000*$0.10=	$2,500
Demand =$72512	$2,100
Total annual cost	$4,600

After Energy Efficiency upgrade
Peak Loading =100% of rated power=	15KW	(20*75%)
Effeciency	80%
Power needed =15/0.8=	18.75	KW
Number of hours in a year	1500
Annual power consumption =15*1500	22500	KWh
Cost of electricity =22500*$0.10=	$2,250
Demand =$718.7512	$1,575
Total annual cost	$3,825

Annual Savings in cost=4600-3825=	$775
Simple paybackin years=10000/775	12.90

Get Answers to Unlimited Questions

Join us to gain access to millions of questions and expert answers. Enjoy exclusive benefits tailored just for you!

Membership Benefits:

Unlimited Question Access with detailed Answers
Zin AI - 3 Million Words
10 Dall-E 3 Images
20 Plot Generations
Conversation with Dialogue Memory
No Ads, Ever!
Access to Our Best AI Platform: Flex AI - Your personal assistant for all your inquiries!

Become a Member

Transcribed Image Text

A 20kW rated motor has an average loading of 75% of rated powerand has an efficiency of 80%. The motor has a peak loading of 100%of rated power. The motor operates 1000 hours a year. The cost ofelectricity is $0.10/kWh and $7/kW-month of demand. Assume themotor operates at periods of peak demand at the facility (i.e. themotor power impacts the billing demand). An energy efficiencyupgrade reduces the average power consumed to an average loading of50% of rated power and reduces the peak power to 75% of ratedpower, but increases the operating hours to 1500 hours per year.There is no change in the efficiency of the motor after theupgrade. The cost of the energy efficiency project is $10,000. Whatis the annual electricity cost of running the motor before andafter the energy efficiency upgrade? What is the simple payback ofthe project?