India’s New Renewables Face 33% Curtailment

One‑third of India’s newly commissioned renewable capacity is being curtailed

India is currently evacuating only about 67% of the 54.8 GW of renewable power that came online in the last year, meaning roughly 33 % is stuck behind the grid. The curtailment is most severe during sunny hours – solar output is being throttled by 50‑60 % in the peak‑generation window. This picture comes from ICRA’s latest assessment of transmission bottlenecks, which notes that the short‑term “temporary general network access” (T‑GNA) route is now handling the bulk of the overflow.

Transmission delays are the primary bottleneck

The root cause is a lag in building new high‑voltage corridors. ICRA estimates that 20,000 km of new lines and 120 GVA of sub‑station capacity are required each year to keep pace with the government’s renewable‑energy targets. So far, only a fraction of the planned interstate transmission system (ISTS) has been completed, leaving large solar‑rich states like Rajasthan and Gujarat to rely on the temporary network. Southern India, where solar output is lower, sees far less curtailment.

Billions of rupees needed to unlock the power

To clear the bottleneck, the ratings agency projects INR 5‑6 trillion (≈ US$52‑63 bn) of investment in the transmission sector between 2026 and 2032. The spend will go toward strengthening existing lines, adding new evacuation capacity, and carving out fresh corridors that can carry the > 900 GW of non‑fossil generation slated for 2035‑36, of which ≈ 548 GW will be solar and wind. Without that cash, the curtailment rate could stay at current levels or even rise as more solar farms come online.

Project timelines are slipping, hurting returns

Delays are not limited to transmission. Of the projects awarded through the tariff‑based competitive bidding (T‑BCB) route up to March 2026, only 12 % hit their scheduled commercial‑operation date. The rest were late by two months to three years, with a median delay of over 10 months. Late commissioning pushes revenue streams further into the future, eroding internal rates of return and making financing more expensive.

What it means for Israel

Even though the grid challenges are Indian, the economics echo what Israeli developers see when transmission or grid‑connection stalls. Using typical Israeli figures – a 10 kW rooftop system in the central region yields about 17 MWh / yr (≈ ₪8,160 at the residential ₪0.48 /kWh tariff) and costs roughly ₪31,500 to install. If a comparable utility‑scale plant in Israel faced a similar level of curtailment, the loss of energy and revenue would be substantial, extending the payback period beyond the typical ~4 years seen under normal conditions. Israeli planners can therefore take a cue from India: securing transmission capacity early is as vital as securing the solar panels themselves. For a deeper dive into Israeli ROI, try our solar ROI calculator and explore the latest market data [/data].

Outlook: faster lines, faster growth

ICRA warns that if the annual 20,000 km of lines and 120 GVA of substations are not delivered on schedule, India could see chronic curtailment that drags down project economics and slows progress toward its renewable‑energy goals. The next five years will be a test of whether policy‑driven financing can outpace land‑acquisition and right‑of‑way hurdles. For investors, the message is clear: grid‑ready projects will command a premium, while those stuck on the temporary network may face reduced returns.