Examkin

Soru

Zorluk: ZorRenewable Energy and Clean Technologies

In geothermal power generation, binary cycle plants are preferred for low-to-medium temperature geothermal reservoirs (typically between 100∘C100^\circ\text{C} and 180∘C180^\circ\text{C}). Which of the following technical principles correctly describes the working mechanism of a binary cycle geothermal power plant?

  1. A
    Geothermal fluid is directly depressurized in a flash tank to generate high-pressure steam that drives a conventional steam turbine.
  2. Geothermal fluid passes through a heat exchanger to vaporize a secondary organic fluid with a low boiling point, which expands through a turbine in a closed loop.Cevap
  3. C
    High-enthalpy geothermal brine undergoes in-situ electrolysis within the reservoir to generate compressed hydrogen gas for fuel cells.
  4. D
    Thermal energy from geothermal brine is converted directly into electricity via solid-state piezoelectric transducers located inside the borehole.

Cevap

In a binary cycle geothermal power plant, geothermal water transfers its heat via a heat exchanger to a secondary working fluid (such as isobutane or pentane) that has a much lower boiling point than water. The secondary fluid vaporizes, drives a closed-loop turbine, and is condensed back into liquid to repeat the cycle, while the cooled geothermal brine is injected back into the reservoir.
The binary cycle geothermal plant operates by circulating warm-to-hot geothermal brine through a heat exchanger. The heat vaporizes a secondary fluid (an organic compound like pentane or isobutane) having a low boiling point. The resulting vapor expands through a turbine generator, turns back into liquid via a condenser, and recycles continuously in a closed system.

Adım Adım Çözüm

1
Identify the defining characteristic of binary cycle power generation
Binary cycle technology utilizes two separate fluid loops (primary geothermal fluid and secondary organic working fluid).
The primary geothermal brine from low-to-medium temperature reservoirs (100∘C100^\circ\text{C} to 180∘C180^\circ\text{C}) lacks sufficient enthalpy to flash into high-pressure steam directly.
2
Analyze the thermodynamic loop interaction
The primary fluid transfers heat to a secondary working fluid with a lower boiling point via a heat exchanger.
Lower boiling point fluids (Organic Rankine Cycle) vaporize efficiently at lower temperatures, producing vapor to drive the turbine.
3
Evaluate environmental and mechanical isolation benefits
Geothermal fluid remains fully contained and is reinjected into the ground without directly contacting the turbine blades.
Prevents turbine corrosion and eliminates atmospheric emissions of dissolved gases.

Anahtar Kavram

Binary Cycle Geothermal Energy and Organic Rankine Cycle (ORC)
Tahmini Süre:2m 0s
Bu soruyu puanla

Konular

Renewable Energy and Clean Technologies

Bu konudan daha fazla soru