In News:

Researchers at IIT Bombay have developed an advanced semi-transparent perovskite solar cell (PSC) layered over a traditional silicon solar cell. This results in a 4-terminal (4T) tandem solar cell that significantly boosts power conversion efficiency (PCE) to ~30%, compared to the current average of ~20% in conventional solar panels.

Key Features and Technology

• Structure: Tandem architecture using a bottom silicon sub-cell and a top layer of indigenously developed halide perovskite semiconductor.
• Material Efficiency: Halide perovskite is one of the most efficient light-absorbing materials and can be locally produced using available chemical resources.
• Cost & Efficiency Gains:
  • Potential to reduce solar power cost to ?1/kWh, down from ?2.5–4/kWh.
  • Offers 25–30% more efficiency compared to standard solar panels.
• Stability Improvements: Previously, PSCs degraded quickly. The new configuration extends lifespan up to 10 years, enhancing durability under heat and low-light conditions.

Strategic Significance for India

• Indigenous Manufacturing: Reduces dependence on imported raw materials, especially those dominated by China.
• Commercialization Plan:
  • Maharashtra government and MAHAGENCO exploring large-scale implementation.
  • ART-PV India Pvt. Ltd., a start-up from IIT Bombay's SINE, aims to deliver a commercial wafer-size solution by December 2027 using indigenous equipment.
• Applications:
  • Rooftop solar installations
  • Building-integrated photovoltaics (BIPV)
  • Vehicle-integrated photovoltaics (VIPV)

Clean Energy Linkage: IIT Bombay is also working with the Maharashtra government to develop green hydrogen solutions. The PSC’s high open-circuit voltage makes it suitable for solar-to-hydrogen (STH) applications, offering performance comparable to costly compound semiconductors but at lower cost and with locally accessible materials.