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EndsemMay 20252019 patternBE Mech

Renewable Energy Technologies (RET) SPPU Endsem Question Paper May 2025

All 8 questions from this SPPU endsem paper, as printed. Read them here or open the PDF.

Open the PDFMost repeated RET questions
Subject code
402051B
Pattern
2019 pattern
Exam
Endsem
Session
May 2025
Max. marks
70
Time
2½ Hours
Semester
VIII
Paper code
[6404]-225

Printed for: B.E. (Mechanical Engineering)

Instructions to the candidates

  1. Solve Q.1 or Q.2, Q.3 or Q.4, Q.5 or Q.6, Q.7 or Q.8.
  2. Neat diagrams must be drawn wherever necessary.
  3. Figures to the right indicate full marks.
  4. Use of electronic pocket calculator is allowed.
  5. Assume suitable data, if necessary.

Questions

  1. Q1

    1. a)

      Explain the following solar cells with neat sketch. i) Single Crystalline - ii) Poly Crystalline

      [6]
    2. b)

      Write a short note on. i) Payback Time and ii) Levelized Energy Cost for solar energy generation

      [6]
    3. c)

      List out and explain the various PV components used in designing PV system.

      [6]

  2. Q2

    1. a)

      Write a short note on. i) Factors affecting electricity generated by a solar cell and ii) Solar Cell Equation

      Also asked:May 2023

      [8]
    2. b)

      Design a standalone PV system for the load specified in the table. Load Number Power Rating (Watt) Usage Hr/day T.V 1 100 2 Refrigerator 2 50 8 Computer 3 18 5 Find: i) Energy supplied (Wh) by the battery to inverter input considering inverter efficiency = 85 %. ii) Considering Depth of Discharge (DOD) of 50 %, calculate the required charge capacity of battery (24V). iii) Considering two days of autonomy, calculate battery charge capacity. iv) Calculate no. of batteries needed for 24 V system voltage if the available battery configuration is 12 V and 100 Ah. v) Calculate the number of panels of 60 W p for the above case considering 6 sunshine hours of 1000 W/m 2 -day. Assume battery efficiency = 80 %, Assume controller circuit efficiency = 100%. 2

      Also asked:May 2024 ·May 2023

      [10]

  3. Q3

    1. a)

      Write a short note on. i) Betz coefficient and ii) Tip Speed Ratio

      [6]
    2. b)

      Explain the Horizontal and Vertical axis wind turbines with neat sketch.

      Also asked:Nov 2025 ·May 2024 ·May 2023

      [6]
    3. c)

      With neat sketch, explain the concept of Upwind and Downwind rotor position for wind turbines.

      [6]

  4. Q4

    1. a)

      List out and explain the components of wind turbine with neat sketch.

      Also asked:Nov 2024 ·May 2023

      [8]
    2. b)

      Wind at 1 standard atmospheric pressure and 15ºC temperature has a velocity of 10 m/s. The turbine has a diameter of 120 m and its operating speed is 40 rev/min at maximum efficiency. Calculate. i) Total power density in the wind stream ii) Maximum obtainable power density assuming,  = 40 %, iii) Total power produced in kW and iv) Torque and axial thrust. Assume air density as  = 1.226 kg/m 3

      [10]

  5. Q5

    1. a)

      Write a short note on. i) Yaw control mechanism used in wind turbine ii) Solar PV tracking

      [6]
    2. b)

      Write a short note on. i) Site selection for wind farm ii) ICT based monitoring and control of wind farm

      [6]
    3. c)

      Write a short note on effect of dust on PV and suggest few remedies for it.

      [5]

  6. Q6

    1. a)

      Explain off shore and on shore wind farms providing their advantages and disadvantages.

      Also asked:May 2023

      [6]
    2. b)

      List out and explain various components of solar photovoltaic system.

      Also asked:May 2023

      [6]
    3. c)

      Explain Pitch controlled and Stall controlled power control for wind turbines. 3

      Also asked:May 2023

      [5]

  7. Q7

    1. a)

      Explain Biogas Digester with neat sketch.

      [6]
    2. b)

      Explain following characteristics of biomass: i) Ultimate analysis ii) Proximate analysis and iii) Thermo- gravimetric analysis

      Also asked:May 2023

      [6]
    3. c)

      Differentiate between Aerobic and Anaerobic digestion.

      [5]

  8. Q8

    1. a)

      Write a short note on Bio-Diesel.

      [6]
    2. b)

      List out and explain various type of biomass.

      Also asked:May 2023

      [5]
    3. c)

      A biomass gasifier is used to run a compression ignition engine. The engine operates in the dual fuel mode with 75 % diesel replacement. The biomass feeding rate for the gasifier is 170 kg/hr. Calculate the power produced by the engine, if the engine efficiency is 28 % and calorific value of biomass is 15500 k.J/kg. Consider efficiency of the gasifier is 0.70. 

      Also asked:Nov 2023 ·May 2023

      [6]