Recently researchers at Stanford University, U.S. studying the impact of emissions from coal-fired power plants on rice and wheat yield in India found that coal power plant emissions reduce crop yield by up to 10% in some states.

Key Findings of the Study

Major Emissions from Coal-Fired Power Plants

• Emit pollutants such as carbon dioxide (CO₂), nitrogen oxides (NOₓ), sulfur oxides (SOₓ), particulate matter, soot, and trace gases.
• These pollutants contribute to smog, acid rain, and reduced air quality, impacting crops and human health.

Effects of Nitrogen Oxides (NOₓ) on Crops

• Phytotoxic properties: NOₓ stresses plants, hinders cellular function, and interferes with crucial enzymatic activities.
• Ozone formation : NOₓ contributes to ozone production, which worsens crop damage.
• Particulate matter accumulation : Blocks sunlight, reducing photosynthesis efficiency.

Crop Yield Losses Due to NO₂ Exposure

• Rice yield losses: 0.0006 metric tons per hectare for every 1 ppb (parts per billion) increase in NO₂.
• Wheat yield losses: More affected than rice due to winter fog and reduced sunlight availability.

Regional Differences in Coal Pollution Impact

• Chhattisgarh: Highest share of NO₂ pollution from coal plants (19% in monsoon, 12.5% in winter).
• Uttar Pradesh: High overall NO₂ levels, but only a small portion comes from coal power.
• Tamil Nadu: Relatively low NO₂ pollution, but majority originates from coal plants.

Economic Impact of Crop Losses

• Rice and wheat yield losses from coal power emissions cost India up to $820 million (₹7,000 crore) annually.
• Targeting highly polluting power stations could significantly reduce losses and improve agricultural productivity.

Sources of Nitrogen Oxides (NOₓ) Emissions

Sustainable Ways to Improve Crop Yield

Reducing Pollution from Coal Power Plants

• Adopting Cleaner Energy Sources: Increase use of solar, wind, and hydropower to reduce coal dependence.
• Installing Advanced Emission Controls: Equip coal plants with Flue Gas Desulfurization (FGD) and Selective Catalytic Reduction (SCR) technology to cut NOₓ emissions.
• Shutting Down Highly Polluting Plants: Prioritize retirement of old, inefficient coal-fired power stations.
• Encouraging Industrial Compliance: Strict enforcement of NOₓ emission standards in power and manufacturing sectors.

Sustainable Agricultural Practices

• Reducing Stubble Burning: Promote alternative uses of crop residue (e.g., biofuel, organic composting).
• Optimizing Fertilizer Use: Adopt precision farming techniques to minimize excess nitrogen application. For example use of Nano Urea improves efficiency of fertilizer application.
• Improving Soil Health: Use organic fertilizers and crop rotation to maintain soil fertility and reduce NOₓ emissions.
• Enhancing Irrigation Methods: Implement drip irrigation and rainwater harvesting to improve water efficiency and reduce plant stress.

Integrating Climate-Smart Policies

• Strengthening Air Quality Regulations: Implement stricter limits on coal power plant emissions.
• Promoting Sustainable Energy Subsidies: Provide incentives for farmers and industries to switch to cleaner alternatives.
• Developing Early Warning Systems: Use satellite monitoring and predictive analytics to mitigate pollution-related agricultural losses.