Solar Radiation Decline in India | 30 Apr 2024

Source: TH

Why in News?

As concerns about climate change continue to escalate, the importance of renewable energy sources like solar power becomes increasingly evident.

• However, a recent study by scientists at the India Meteorological Department (IMD) has revealed a concerning trend about the quantity of solar radiation available for conversion into electricity by solar panels is on the decline in several locations across India.

What are the Key Highlights of the Study?

• Aerosol Load:
  • Increased aerosol load from carbon emissions, fossil fuel burning, and dust, along with clouding, contribute to the decline in solar radiation.
  • Aerosols absorb the sunlight and deflect it away from the ground and they can also precipitate the formation of dense clouds that again block sunlight.
  • The efficiency of solar panels is significantly influenced by the amount of sunlight incident on them.

• Decline in Solar Photovoltaic (SPV) Potential:
  • Analysis reveals a widespread decline in SPV potential across all monitored stations.
    • SPV is the amount of radiation that may be practically available to be converted to electricity by panels.
  • SPV potential showed a general decline in all stations which included Ahmedabad, Chennai, Goa, Jodhpur, Kolkata, Mumbai, Nagpur, New Delhi, Pune, Shillong, Thiruvananthapuram, and Vishakhapatnam.
  • India’s largest solar parks are located in the northwest, particularly Gujarat and Rajasthan, and cities in both these States are also showing a decrease in SPV potential.
• Global Solar Radiation (GR) over India:
  • Global solar radiation (GR) is the total amount of solar radiation that is being received per unit area on the earth's surface.
    • GR is maximum over northwest India and inland peninsular India, minimum over extreme north and northeast India.
      • Reduction attributed to increased atmospheric turbidity and cloudiness. Monsoon clouds reduce the GR over most parts of India.
    • Maximum GR in pre-monsoon season for most stations, except Srinagar.
    • Minimum GR varies between monsoon, post-monsoon, or winter depending on the station.
• Diffuse Radiation (DR):
  • Diffuse radiation refers to solar radiation scattered by atmospheric particles.
    • Clear skies transmit a large percentage of solar radiation, resulting in relatively small diffuse radiation.
    • In contrast, a partly cloudy or turbid atmosphere exhibits high diffuse radiation due to increased scattering of solar radiation by atmospheric particles.
  • Significant increase in DR observed in more than 50% of stations, especially in northwest and some parts of peninsular India.
    • Increase attributed to increased atmospheric turbidity and cloudiness.

What are the Implications for India's Solar Power Goals?

• Current Scenario:
  • India’s current installed solar power capacity is about 81 GW (1 GW is 1,000 megawatts), or roughly 17% of the total installed electricity.
  • India stands 4^th globally in Renewable Energy Installed Capacity, 4^th in Wind Power capacity and 5^th in Solar Power capacity (as per International Renewable Energy Agency - Renewable capacity statistics 2023).
• Ambitious Targets:
  • India has ambitious plans of sourcing about 500 GW, nearly half its requirement of electricity, from non-fossil fuel sources by 2030.
    • This would mean at least 280 GW of solar power by that year or at least 40 GW of solar capacity being annually added until 2030.
• Challenges:
  • Despite ambitious goals, the country has struggled to meet its targets, with annual additions barely crossing 13 GW in the last five years.
  • Factors like the Covid-19 pandemic have been cited as hindrances to progress and the country was on track to add between 25-40 GW annually in the coming years.
  • And other challenges for solar power development in India include land acquisition complexities, grid integration issues, slow growth of rooftop solar, limited availability of storage technology, and a need for more innovation.

What are the Government Initiatives Related to Solar Energy?

• The Production Linked Incentive Scheme (PLI) for the National Programme on High-Efficiency Solar PV Modules.
• Solar Park Scheme.
• PM-KUSUM.
• Rooftop Solar Programme.
• International Solar Alliance (ISA).

Way Forward

• Analyse the aerosol types contributing most to the decline (e.g., black carbon from vehicles, industrial dust).
  • Enact targeted policies to address those sources. Partner with local authorities to tackle regional pollution hotspots.
• Focus on promoting bifacial solar panels that capture sunlight from both sides, potentially increasing generation even with diffused light.
  • Incentivise domestic manufacturing of these panels to reduce reliance on imports and create green jobs.
• Partner with international research organisations like the International Renewable Energy Agency (IRENA) to share data and best practices on mitigating the impact of air pollution on solar radiation.
• Develop and deploy Artificial Intelligence-powered robotic systems for automated cleaning of solar panels in arid regions.
  • Dust accumulation on panels significantly reduces efficiency. These AI cleaners can optimise cleaning schedules based on weather data and dust forecasts, maximising solar power generation.
• Enact building codes mandating pre-installation of rooftop solar panels on all new commercial and government buildings.
  • This can significantly increase rooftop solar adoption and reduce reliance on traditional grid power.