PTE · Describe Image

Renewable Energy Technology: PTE Describe Image practice questions

4 original Describe Image questions. Question 1 is free to record, play back and compare with a sample answer right here; log in free to practise the rest in the BandLadder app.
  • 4 questions
  • Question 1 free, no login
  • PTE Academic and PTE Core
1

Anaerobic Digestion Biogas Production

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Look at the image below. You have 25 seconds to study it, then 40 seconds to describe in detail what it shows.

Anaerobic Digestion Biogas Process. Stage 1: Organic waste collection and sorting. Stage 2: Mechanical pre-treatment and shredding. Stage 3: Anaerobic digestion in sealed tank. Stage 4: Biogas collection and desulphurisation. Stage 5: Combined heat and power generation. Stage 6: Digestate processing into biofertiliser.

Anaerobic Digestion Biogas Process
  1. 1.Organic waste collection and sorting
  2. 2.Mechanical pre-treatment and shredding
  3. 3.Anaerobic digestion in sealed tank
  4. 4.Biogas collection and desulphurisation
  5. 5.Combined heat and power generation
  6. 6.Digestate processing into biofertiliser

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Questions 2–4

Look at the image below. You have 25 seconds to study it, then 40 seconds to describe in detail what it shows.

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2

Biomass Pellet Energy Output

Energy Content of Biomass Feedstocks (megajoules per kilogram). Raw Feedstock: Wheat Straw 14, Rice Husk 13, Softwood Sawdust 16, Hardwood Chips 15, Olive Pomace 17. Densified Pellets: Wheat Straw 18, Rice Husk 17, Softwood Sawdust 21, Hardwood Chips 20, Olive Pomace 22.

Energy Content of Biomass Feedstocks (megajoules per kilogram)
0510152025Wheat StrawRice HuskSoftwood SawdustHardwood ChipsOlive Pomace
  • Raw Feedstock
  • Densified Pellets
View the data
Wheat StrawRice HuskSoftwood SawdustHardwood ChipsOlive Pomace
Raw Feedstock1413161517
Densified Pellets1817212022
3

Wave Energy Converter Comparison

Operational Attributes of Wave Energy Converters. Columns: Device Type, Water Depth, Capacity Factor, Capital Cost Rating. Point Absorber, Deep water, 38%, Moderate. Oscillating Water Column, Nearshore, 29%, High. Attenuator, Deep water, 34%, High. Overtopping Reservoir, Shoreline, 22%, Very High.

Operational Attributes of Wave Energy Converters
Device TypeWater DepthCapacity FactorCapital Cost Rating
Point AbsorberDeep water38%Moderate
Oscillating Water ColumnNearshore29%High
AttenuatorDeep water34%High
Overtopping ReservoirShoreline22%Very High
4

Hybrid Renewable Microgrid Layout

Remote Community Microgrid Compound, north at the top. Solar Array Field in the north-west, Battery Bank in the north-east, Control Building in the east, Biomass Boiler in the south-west, Substation Yard in the south-east.

Remote Community Microgrid Compound
Solar Array FieldBattery BankControl BuildingBiomass BoilerSubstation YardN

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