Solar Radiation Geometry & Measurement: Solar Constant, Beam & Diffuse Radiation, Pyranometers & Pyrheliometers - Renewable Energy Engineering | Agrigyan

• Tracking Mechanism of Scheffler Solar Concentrators:
• Design Concept: Invented by Wolfgang Scheffler, this system utilizes a flexible elliptical section of a paraboloid that concentrates direct sunlight onto a stationary focal receiver located inside an enclosed kitchen or workshop.
• Tracking System: Employs two-axis tracking:
• Daily polar tracking: Automatic clockwork or motorized rotation about an axis parallel to Earth's polar axis ($15^\circ/\text{h}$) to follow the sun from east to west.
• Seasonal tracking/deformation: Adjusts the tilt angle and physically flexes the crossbars of the reflector surface to match solar declination changes throughout the seasons.
• Conclusion: 2-axis tracking (Option 3).

Correct option: (3) 2-axis tracking

• Operating Temperatures in Parabolic Trough Collectors (PTC):
• Concentration Mechanism: Parabolic Trough Collectors are single-axis tracking line-focus concentrating solar collectors with a geometric concentration ratio of $30 - 80$.
• Operating Temperature: Synthetic thermal oils (e.g., Therminol VP-1, Dowtherm A) or molten salts pumped through evacuated receiver tubes placed along the focal line attain working temperatures up to $400^\circ\text{C}$ ($350 - 400^\circ\text{C}$), generating superheated steam for industrial process heat and power plants.
• Conclusion: 400°C (Option 2).

Correct option: (2) 400 °c