A high headline growth number may hide structural weakness. Analyse with reference to recent trends in India's core industries.

The Index of Core Industries (ICI) grew 7.9% in September 2026, the fastest growth in the new 2022-23 series [1]. Taken apart sector by sector, the figure shows real strength in a few areas. Much of it, however, comes from weather and a statistical base effect rather than lasting demand.

Strengths behind the headline

• Iron ore grew 18.4% and refinery products grew 10.3%. Cumulative April–September growth was 5.1%, roughly double the previous year's 2.5% [1].
• Iron ore was added to the basket in the revised series [2]. Its growth reflects demand from steel and construction, which is a genuine sign of investment.

Weaknesses the headline hides

• Weather-driven demand: electricity grew 11.4% and coal 10.7% [1]. This followed a heat wave linked to El Niño. That demand will fall away as winter sets in.
• Restocking, not new demand: by September, dozens of thermal plants were at critical coal-stock levels under CEA norms [3]. Part of coal's jump was mines refilling empty stockyards.
• Base effect: energy output was weak in September 2025, which makes this year's growth rate look larger [1]. Coal had contracted for most of 2026, including in August [1].
• Weight concentration: electricity carries the largest weight in the index, about 31% [2]. A single hot season can therefore move the whole index.
• Structural laggards: crude oil, natural gas and fertilisers contracted [1]. This points to continued dependence on imported energy. Steel grew only 4.9%, which is modest [1].
• Limited coverage: the core industries make up only part of the IIP [2]. A spike driven by power output says little about labour-intensive manufacturing.

Heat wave → power demand ↑ → coal stocks ↓ → coal output ↑ → ICI ↑
             (temporary)                       (refill)       (headline)

Fig: How weather can inflate core-sector growth

Reading the signal correctly

• Check the weights, base effect, cumulative trend and cause together before treating any month as a recovery.
• Planning should tie coal stocks to the climate forecast and expand domestic oil and gas exploration.

In short, September's 7.9% combines a real but narrow gain in iron ore and refining with a large, temporary bump from weather and the base effect. The index should be treated as an early warning that needs checking against the IIP and investment data. Lasting growth will need broad-based investment and energy security, in line with SDG 9 on resilient infrastructure.