ME-803-B Energy Conservation, Management and Audit - May 2023 Question Paper

Under each question, How to answer lists the points an answer should cover, outlined by CampusPrep from the syllabus. Check the details against your textbook.

1. 7 Marks
   aExplain the energy management opportunities in motors.
   How to answer

   • Define energy management opportunities in motors
   • List high-efficiency motors, proper sizing, VSDs
   • Mention power factor improvement, maintenance, load matching
   • Mention operating practices and rewinding effects
2. 7 Marks
   bWhat is the Duties and responsibilities of energy managers?
   How to answer

   • Define role of energy manager per Energy Conservation Act
   • List energy audit, monitoring, reporting duties
   • Mention awareness, training, management liaison
   • Mention implementation of conservation measures
3. 14 Marks
   What is meant by waste heat recovery? What are the direct and indirect benefits of waste heat recovery?
   How to answer

   • Define waste heat recovery and sources
   • Explain direct benefits: fuel saving, efficiency, capacity
   • Explain indirect benefits: emission reduction, equipment life
   • Give examples of recovery devices
4. 7 Marks
   aWhat is meant by simple payback period? Calculate simple payback period for a boiler that cost Rs.75.00 lakhs to purchase and Rs. 5 lakhs per year on an average to operate and maintain and is expected to annually save Rs. 30 lakhs?
   How to answer

   • Define simple payback period formula
   • Compute net annual saving = 30 - 5 = 25 lakhs
   • Calculate payback = 75 / 25 = 3 years
   • Interpret result and limitations
5. 7 Marks
   bWrite short note on force field analysis and its application.
   How to answer

   • Define force field analysis concept
   • Explain driving vs restraining forces
   • Outline steps to conduct analysis
   • Mention applications in energy management/change
6. 5 Marks
   aExplain any five energy management opportunities in lighting systems.
   How to answer

   • List five opportunities: efficient lamps, ballasts, controls
   • Mention daylighting, occupancy sensors, maintenance
   • Mention voltage optimization, reflectors
   • Mention design lux levels and task lighting
7. 5 Marks
   bExplain the maximum demand.
   How to answer

   • Define maximum demand in kVA/kW
   • Explain demand interval and billing relevance
   • Mention contract demand vs actual demand
   • Mention load factor relation
8. 4 Marks
   cExplain the methods to control maximum demands.
   How to answer

   • List demand control methods: load shedding, staggering
   • Mention peak shaving, capacitor, storage
   • Mention monitoring, alarms, EMS
   • Mention tariff and scheduling strategies
9. 7 Marks
   aWhat is meant by Steam traps? Explain the operation of thermostatic steam trap.
   How to answer

   • Define steam trap purpose
   • Explain thermostatic trap principle with bellows/expansion
   • Describe operation cycle: air/condensate discharge
   • Mention applications and advantages
10. 7 Marks
    bExplain how setting a lower evaporator temperature helps in reducing the power consumption of an air conditioning system? List down any three energy saving measures in domestic air conditioning system.
    How to answer

    • Clarify evaporator temperature vs power relation
    • Explain COP, pressure ratio and compressor work
    • List three domestic AC saving measures
    • Mention thermostat setting, maintenance, insulation
11. 5 Marks
    aDifferentiate between simple payback period and net present value method.
    How to answer

    • Define simple payback: time to recover cost ignoring time value
    • Define NPV: discounted cash flows minus investment
    • Compare on basis of time value, profitability, decision rule
    • Mention merits/demerits with formula
12. 5 Marks
    bExplain the importance of Thermal insulation for thermal energy management.
    How to answer

    • Define thermal insulation purpose
    • Explain heat loss reduction, fuel saving
    • Mention condensation, process control benefits
    • Mention types and economic thickness
13. 4 Marks
    cWhat is the effect of low power factor of the system?
    How to answer

    • Define power factor and low pf causes
    • Explain higher current, losses, penalties
    • Mention voltage drop and capacity blocking
    • Mention need for correction
14. 7 Marks
    aWhat is meant by loading of motor? Why does the efficiency of motor reduce when it operates at lower loading? List down any 2 steps to improve the operating efficiency of under-loaded motors.
    How to answer

    • Define motor loading and load factor
    • Explain fixed vs variable losses at low load
    • Explain efficiency drop due to poor utilization
    • List 2 steps: downsizing, VSD, proper selection
15. 7 Marks
    bExplain the Concepts of energy efficient motors.
    How to answer

    • Define energy efficient motors (IE classes)
    • Explain design features: low-loss steel, copper
    • Mention higher efficiency, lower slip and heating
    • Mention life-cycle cost benefits
16. 14 Marks
    A paper manufacturing company has a contract demand of 5000 kVA with the power supply company. The average maximum demand of the plant is 3850 kVA/month at a power factor of 0.95. The maximum demand is billed at the rate of Rs.500/kVA/month. The minimum billable maximum demand is 75% of the contract demand. An incentive of 0.5% reduction in energy charges component of electricity bill is provided for every 0.01 increase in power factor over and above 0.95. The average energy charge component of the electricity bill per month for the plant is Rs. 20 lakhs. The plant decides to increase the power factor to unity by installing capacitor banks. Find the annual reduction in demand component charges and energy component charges? Find the kVAR required to improve the power factor from 0.95 to unity?
    How to answer

    • Compute billable demand: max(3850, 75% of 5000)
    • Compute demand charge saving and energy incentive for 0.95 to 1.0
    • Compute kVAR = kW*tan(phi) with kW from kVA*pf
    • Calculate annual reductions: demand and energy components