increasing from 179 TW-hr in 1985 to 1,057 TW-hr in 2012. The majority of the increase came from coal-fired plants and non-conventional renewable energy sources (RES), with the contribution from natural gas, oil, and hydro plants decreasing in 2012–2017. The gross utility electricity generation (excluding imports from Bhutan) was 1,384 billion kWh in 2019–20, representing 1.0% annual growth compared to 2018–2019. The contribution from renewable energy sources was nearly 20% of the total. In 2019–20, all the incremental electricity generation is contributed by renewable energy sources as the power generation from fossil fuels decreased. During the year 2020–2021, the utility power generation has decreased by 0.8% (11.3 billion kWh) with a reduction in power generation from fossil fuels by 1% and power generation from non-fossil sources is more or less same of the previous year. In 2020–21, India exported more electricity than it imported from neighboring countries. Solar power generation in 2020–21, occupied third place after coal and hydropower generations surpassing wind, gas and nuclear power generations. Notes: Coal includes lignite; Misc: includes contributions from emergency diesel generator sets, roof top solar, captive power generation from below 1 MW capacity plants, etc.; *Hydro includes pumped storage generation; na = data not available. Thermal power Pollution from coal-based power plants In India the Commercial Energy makes 74% of total energy, of which coal based energy production is around 72–75%, as per 2020 data. For utility power generation, India consumed 622.22 million tons of coal during 2019–20 which is less by 1% compared to 628.94 million tons during 2018–19. However coal imports for utility power generation increased by 12.3% during year 2019–20 at 69.22 million tons from 61.66 million tons during 2018–19. A large part of the Indian coal reserve is similar to Gondwana coal: it is of low calorific value and high ash content, with poor fuel value. On average, Indian coal has a gross calorific value (GCV) of about 4500 Kcal/kg, whereas in Australia, for example, the GCV is about 6500 Kcal/kg . The result is that Indian power plants using India's coal supply consume about 0.7 kg of coal per kWh of power generation, whereas in the United States thermal power plants consume about 0.45 kg of coal per kWh. In 2017, India imported nearly 130 Mtoe (nearly 200 million tons) of steam coal and coking coal, 29% of total consumption, to meet the demand in electricity, cement and