Solar Plus Storage Nears 90% Grid Share Capability in India, But Monsoon Remains Challenge: EMBER

Solar power paired with battery storage can potentially meet up to 90% of India’s electricity demand at a competitive cost of Rs. 5.06/kWh, according to a new report by Ember. The finding marks a significant shift in the economics of clean energy, with battery costs falling sharply over the past two years. The analysis is based on a thought experiment conducted by Ember. While just a theoretical possibility right now, the finding could have serious implucations in the long term should  climnate impact on the ground force a global rethink and pressure to ease away from coal faster. For now, India has thermal well into its plans for 2060 and beyond. 

In India, solar has the potential to emerge as a dominant source of electricity. Ember’s modelling shows that solar combined with battery storage could supply 90% of the country’s electricity demand at a levelised cost of electricity (LCOE) of INR 5.06/kWh ($56/MWh), placing it firmly within the range of existing power procurement costs.

While higher shares—including 100%—are technically feasible, the Ember report noted that economics become progressively challenging beyond the 90% threshold. Each additional percentage point requires disproportionately higher investments in solar capacity and storage, pushing up overall system costs. Moreover, the research noted that with other clean energy sources such as wind, hydro, and nuclear already part of the mix, India is unlikely to require a fully solar-based system.

Battery storage plays a critical role by converting daytime solar generation into reliable evening electricity, effectively addressing intermittency concerns. Solar-plus-storage systems are already delivering electricity at costs lower than prevailing power purchase prices in many states, while also rivalling coal in terms of reliability. “From here, the economics only become more compelling,” said Duttatreya Das.

Meeting 90% Demand Requires 930 GW Solar—A Fraction of India’s Potential

India’s electricity demand stood at just over 2,000 terawatt-hours (TWh) in 2024. Meeting 90% of this demand would require 930 GW of solar capacity—less than one-third of the country’s estimated 3,343 GW of feasible ground-mounted solar potential, the research added. 

In addition, around 2,560 gigawatt-hours (GWh) of battery storage would be needed. This translates to roughly 4.9 GW of solar capacity and 13.5 GWh of battery storage for every 1 GW of annual average demand load. The modelling demonstrates that solar paired with battery storage could have met 90% of India’s 2024 electricity demand with 930 GW of solar and 2,560 GWh of storage—highlighting how a relatively small share of the country’s vast solar potential could deliver outsized results.

However, the key constraint is not battery availability, but extended periods of low solar generation—particularly during the monsoon. Even so, the LCOE of INR 5.06/kWh ($56/MWh) remains competitive. Importantly, India’s demand patterns are well aligned with solar output, with peak demand often coinciding with high solar radiation and easing during the monsoon months when solar generation dips.

10 States Can Meet 83%–92% of Demand with Solar + Storage

India currently has 143 GW of installed solar capacity as of February 2026—just around 4% of its estimated 3,343 GW potential. Yet, this potential alone is sufficient to generate nearly three times the country’s 2024 electricity demand. In 2025, solar accounted for 9.4% of total electricity generation according to the research. 

At the state level, the report finds that solar and battery systems could meet between 83% and 92% of electricity demand across the 10 largest power-consuming states. Seven states could achieve 90% or higher, led by Andhra Pradesh at 92%, while Uttar Pradesh ranks lowest at 83%.

This variation is largely driven by differences in demand patterns. States with higher electricity consumption during sunnier months tend to achieve higher solar shares, whereas states with strong monsoon-season demand—such as Uttar Pradesh and West Bengal—face greater challenges.

Demand–Solar Alignment Emerges as a Critical Factor

According to the research, a key driver of these outcomes is the seasonal alignment between electricity demand and solar generation. States where peak demand coincides with peak solar output require less additional capacity to achieve high renewable shares. In high-resource regions, solar capacity factors peak in March and April—around 20% above the annual average—before dropping to 28% below average in July during the monsoon.

This alignment is particularly favourable in Andhra Pradesh, Maharashtra, Karnataka, Tamil Nadu, and Telangana, where demand during high-solar months is 10–29% above the annual average. Except for Tamil Nadu, these states also see demand dip below average in July by 6–18%, further easing system balancing.

States such as Gujarat, Rajasthan, and Madhya Pradesh also display relatively stable demand profiles, which helps maintain system efficiency. In contrast, Uttar Pradesh and West Bengal stand out as less favourable cases, with demand during July—when solar output is weakest—rising 38% and 24% above the annual average, respectively.

Solar + BESS Already Cheaper in Many States

The report highlights that solar-plus-storage systems are already cost-competitive. Modelled LCOE ranges from INR 4.96/kWh ($55/MWh) in Andhra Pradesh to INR 5.48/kWh ($60/MWh) in Uttar Pradesh. In six of the ten largest states, where solar and storage can meet 90% or more of electricity demand, costs are already below current average power purchase prices. On average, LCOE is around 15% lower across these states. For example, in Gujarat, the cost of meeting 90% demand through solar and storage is 7% lower than the state’s current procurement cost. In Karnataka, the savings are even more pronounced, with costs 21% lower.

Even after accounting for transmission, the economics remain attractive. Transmission charges typically range from INR 0.7–0.9/kWh, and sourcing power from distant states could raise landed costs by INR 1.2–1.5/kWh—still within competitive levels.

States Can Procure Up to 99% Power from Solar + Storage

Ember’s analysis further shows that all 10 major states could procure at least 75%—and up to 99%—of their electricity from solar and battery storage at costs lower than current procurement levels. In Madhya Pradesh, which has the lowest existing power purchase cost (INR 4.75/kWh), solar-plus-storage systems could meet up to 76% of demand before exceeding current costs. In six states, however, solar and storage could meet 90% or more of demand without surpassing today’s procurement costs. In these cases, the LCOE for systems meeting between 95% and over 99% of demand ranges from INR 5.5 to 6.6/kWh.

Auction Prices Signal Further Cost Declines

Recent auction results reinforce the improving economics. Solar-plus-storage projects in 2025 were awarded at tariffs of INR 2.9–3.5/kWh for systems with four-hour battery storage. More recently, India’s first solar-plus-6-hour BESS auction in early 2026 discovered a tariff of INR 3.12/kWh.

These projects typically require developers to meet specified generation thresholds and supply evening peak demand with around 70% monthly reliability. Many are expected to be commissioned over the next two to three years and already reflect anticipated declines in battery costs.