SECI, Andhra Pradesh Ink 1.2-GWh Storage Deal

• SECI, Andhra Pradesh to deploy 1,200‑MWh battery with 50‑MW hybrid solar—storing midday sun for peak power, slashing curtailment, stabilizing grids, and monetizing timed MWh under new capacity tariffs.

SECI and Andhra Pradesh signed a pact to build a 1,200‑MWh battery paired with a 50‑MW hybrid solar park, designed to store midday solar and deliver power at evening peaks and during outages. Co-located, containerized lithium‑ion units with grid-forming inverters will share interconnection, cutting losses and capital costs.

Targeted at curtailment and price spikes in a solar-rich state, the multi-hour system can provide frequency and voltage support, reserves, fault ride-through and black-start. Execution hinges on orders for transformers and MV gear and on safeguards. SECI’s bankable tenders and evolving capacity/availability tariffs underpin returns, signaling a shift to valuing timed megawatt-hours.

How will SECI–Andhra’s grid-forming, co-located BESS curb curtailment and price spikes?

• Absorbs midday surplus at the point of interconnection, preventing reverse power-flow limits from forcing solar curtailment and freeing upstream lines during congested hours.
  
• Releases stored energy across evening peaks and morning ramps, shaving net demand spikes that trigger high marginal prices on DAM/RTM.
  
• Grid-forming inverters provide virtual inertia, fast frequency response, and volt/VAR control, stabilizing the local node so more solar can be dispatched without tripping or protection-driven curtailment.
• Supplies spinning/non-spinning reserves and ramping capacity, reducing reliance on costly gas/diesel peakers that set extreme prices during tight conditions.
  
• Delivers fault ride-through, islanding, and black-start, keeping feeders energized through disturbances and avoiding demand spikes when loads reconnect after outages.
  
• Participates in AGC and secondary/tertiary control, smoothing intra-hour imbalances that otherwise translate into penalty costs and price volatility.
• Co-location and shared interconnection minimize conversion and wheeling losses, improving round-trip economics so more stored MWh can be delivered at peak without extra grid fees.
  
• Eases substation and corridor congestion by charging during local bottlenecks and discharging when constraints relax, turning potential curtailment into saleable, timed MWh.
  
• Dampens price volatility via arbitrage: buying (charging) when prices collapse at solar noon and selling (discharging) when scarcity premia emerge, narrowing spreads.
  
• Supports capacity/availability contracts that monetize firm, on-peak delivery, shifting value from undifferentiated energy to deliverability and reducing merchant exposure to spikes.
  
• Increases the solar park’s capacity factor and revenue certainty by converting otherwise-curtailed output into contracted peak supply.
  
• Provides seasonal and weather-driven flexibility (cloud cover, monsoon variability, cyclones), limiting sudden net-load ramps that precipitate price surges.
  
• Reduces DSM and deviation penalties for the state by containing forecast errors with fast, accurate balancing at the node.
  
• Defers grid upgrades by acting as a local buffer, lowering the need for immediate transmission reinforcement that curtailment rules would otherwise enforce.
  
• Enhances reliability for C&I offtakers tied to the park’s feeders, curbing backup diesel use and associated high-cost, spike-prone demand during grid stress.