India’s Renewable Energy Firms Struggle With Weather Forecasts, Risk Grid Penalties

India's renewable energy producers on December 3 flagged the lack of effective weather forecasting models in the country, as the Central Electricity Regulatory Commission, the power regulator proposed stricter rules on how closely developers must adhere to their grid supply commitments, reported Reuters.

These gaps in forecasting technology and data update frequency make it difficult for producers to meet their grid commitments, raising the risk of supply disruptions.

CERC had issued stringent rules in a September draft for wind and solar power producers under the Deviation Settlement Mechanism, a system that fines companies when their actual power supply to the grid strays too far from their forecasts.

The draft framework aims to gradually narrow the permissible gap between the amount of electricity producers commit to supply and what they actually generate and was due to come into effect from April 2026.

According to Reuters, in a public hearing, several clean energy developers flagged the absence of precise hyperlocal weather forecasting models in the country that can aid them in meeting their promised power generation to the grid.

India has a tropical monsoon climate with unpredictable, abrupt weather transitions, making it prone to weather forecasting errors compared with mid-latitudes like Europe and the US that have predictable seasonal cycles, companies said, calling for improved weather forecasting technology.

Meanwhile, the radars deployed by the Indian government are from the disaster management perspective and there is no deployment in the renewable-energy-rich areas to assist in the energy forecasting, representatives of IndiGrid Solar told the commission.

Government-run India Meteorological Department does provide the base weather data used for forecasts across the nation, but its data are updated only once every six hours, making accurate short-term forecasting "next to impossible", they said.

Last week, Reuters reported that the country's renewable energy ministry had urged the power regulator to delay plans for stricter rules, saying hefty penalties could deter investments into the emerging clean energy sector.

Forecast Accuracy Matters

Improved weather forecasting plays a vital role in boosting reliability of variable renewable output.

According to a report published by the International Renewable Energy Agency (IRENA) titled ‘Advanced Forecasting of Variable Renewable Power Generation’ in 2020, accurate short- and long- term forecasts help generators and grid operators better estimate solar and wind generation, thereby, reducing imbalances, grid strain and deviation penalties.

In addition, the IRENA report further stated that power generation forecasts have become more accurate driven by an increase in computing power and improvement in algorithms. In a similar vein, due to the increasing use of AI fuelled by big data, predictions for short-term weather and energy generation have become more detailed. These factors can greatly help in the integration of renewable power into the grid.