{"id":515,"date":"2026-07-07T12:25:27","date_gmt":"2026-07-07T10:25:27","guid":{"rendered":"https:\/\/www.calibsun.com\/?page_id=515"},"modified":"2026-08-19T14:59:31","modified_gmt":"2026-08-19T12:59:31","slug":"%e5%8d%b0%e5%ba%a6%e5%a4%aa%e9%98%b3%e8%83%bd","status":"publish","type":"page","link":"https:\/\/www.calibsun.com\/zh\/india-solar-energy\/","title":{"rendered":"\u592a\u9633\u80fd\u53ef\u518d\u751f\u80fd\u6e90 | \u5370\u5ea6\u7684\u592a\u9633\u80fd"},"content":{"rendered":"\t\t
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India<\/span> \n
Solar forecasting<\/h1>\t\t\t\t<\/div>\n\t\t
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India crossed 164.6 GW of installed solar in July 2026, and one third of the capacity recently commissioned cannot always reach the grid. Since 1 April 2026 the deviation band is half what it was. Both constraints resolve inside the same fifteen-minute block.<\/p>\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t

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Solar forecasting in India<\/h2>\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t
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India crossed 164.6 GW of installed solar capacity on 31 July 2026, and added a record 15.3 GW in the first quarter of 2026 alone, 12.6 GW of it utility-scale. Gujarat and Rajasthan carried close to four fifths of those large-scale additions.<\/p>

The constraint has moved with them. Around one third of the renewable capacity recently commissioned in India now faces grid curtailment, and under temporary general network access the curtailed share reaches 50 to 60 percent during solar generation hours. Curtailment is most pronounced in exactly the two states that are building fastest.<\/p>

A second constraint arrived on 1 April 2026. The tolerance band for solar and wind-solar hybrid stations moved from plus or minus 10 percent to plus or minus 5 percent, so every 15-minute block that leaves the band is charged twice as easily as in 2025.<\/p>

Together these two forces change what a schedule is worth. Output that cannot be evacuated has to be stored or shifted, and output that is declared wrongly is charged. Both decisions are made inside the hour.<\/p>\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t

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Curtailment first, deviation charges second<\/h2>\t\t\t\t<\/div>\n\t\t\t\t
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Indian solar is scheduled in 15-minute blocks. The generator, or a Qualified Coordinating Agency acting for it, submits a day-ahead schedule to the load despatch centre and revises it during the day. Settlement compares injection to schedule, block by block, and charges the gap.<\/p>

Curtailment sits upstream of that. Transmission build-out is running behind connection, with a pipeline of 107 GW awaiting interstate integration between the 2026 and 2031 financial years, and transmission projects still exposed to land acquisition and right of way delays. Curtailment erodes plant load factors by up to four percentage points in the states with the highest penetration.<\/p>

The deviation charge is concentrated, not spread. On a 150 MW plant in the SRLDC area between October 2023 and March 2024, the blocks deviating by more than 30 percent were 2.35 percent of all blocks and carried 45.12 percent of the penalty paid. Forecasting in India is a tail problem.<\/p>\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t

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Solar in India: the market in figures<\/h2>\t\t\t\t<\/div>\n\t\t
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Photo: Tata Power<\/figcaption>\n\t\t\t\t\t\t\t\t\t\t<\/figure>\n\t\t\t\t\t\t\t\t\t<\/div>\n\t\t
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India is the second-largest national market for renewables growth worldwide, with close to 345 GW of renewable capacity expected between 2025 and 2030, nearly 60 percent of it auction-driven utility-scale solar.<\/p>\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t

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The physical loss is not theoretical. On a 350 MW plant in Bikaner, clear-day generation averaged 2,843 MWh while the worst cloudy day delivered 310 MWh, a shortfall of 89 percent. The schedule for that day had been submitted the day before.<\/p>\t\t\t\t\t\t\t\t<\/div>\n\t\t

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Indicator<\/p>\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t

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Value<\/p>\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t

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Source<\/p>\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t

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Installed solar capacity<\/p>\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t

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164,595 MW at 31 July 2026<\/p>\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t

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MNRE, physical progress<\/p>\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t

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Solar added in the first quarter of 2026<\/p>\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t

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15.3 GW, a record, 12.6 GW utility-scale<\/p>\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t

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SPDA, June 2026<\/p>\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t

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Share taken by Gujarat and Rajasthan<\/p>\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t

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Close to four fifths of large-scale additions<\/p>\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t

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SPDA, June 2026<\/p>\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t

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Renewable capacity facing curtailment<\/p>\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t

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33 percent of 54.8 GW recently commissioned<\/p>\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t

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ICRA, May 2026<\/p>\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t

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Curtailment under temporary network access<\/p>\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t

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50 to 60 percent during solar hours<\/p>\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t

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ICRA, May 2026<\/p>\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t

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Effect on plant load factor<\/p>\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t

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Up to 4 percentage points in high-penetration states<\/p>\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t

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Mordor Intelligence, 2026<\/p>\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t

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Deviation tolerance band since 1 April 2026<\/p>\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t

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Plus or minus 5 percent, against 10 percent before<\/p>\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t

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CERC Order, Petition 9\/SM\/2025<\/p>\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t

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Key context<\/h3>\t\t\t\t<\/div>\n\t\t\t\t
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Two constraints now act on the same 15-minute block. Curtailment decides how much of the available output can physically reach the grid, and the deviation band decides how much of what is declared has to be delivered. A plant that forecasts well manages both. A plant that does not pays twice.<\/p>\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t

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CERC, the states, open access, and now storage<\/h2>\t\t\t\t<\/div>\n\t\t
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Source: Sustainable Projects Developers Association<\/figcaption>\n\t\t\t\t\t\t\t\t\t\t<\/figure>\n\t\t\t\t\t\t\t\t\t<\/div>\n\t\t
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Four rulebooks on the same 15-minute block<\/h3>\t\t\t\t<\/div>\n\t\t\t\t
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CERC<\/strong> governs inter-state entities. It halved the solar tolerance band on 1 April 2026 and set a trajectory for the coefficient X, which decides whether deviation is measured against available capacity or against the submitted schedule. X holds at 100 percent until 31 March 2027, then falls to 90, 75, 55 and 30 percent, and reaches 0 percent on 1 April 2031. As X falls the denominator shrinks, and the same absolute error yields a larger deviation.<\/p>

Each state commission<\/strong> sets its own bands and charges for intra-state sales. Gujarat and Rajasthan concentrate both the new capacity and the curtailment, and their rules are not the central ones. The band, the revision gate and the charge schedule therefore differ from one connection point to the next.<\/p>

Short Term Open Access<\/strong> adds a third clock. A plant selling through STOA books capacity for days or weeks rather than for the life of a contract, declares a schedule against that booking, and carries the deviation on it. Open access volumes are growing as commercial and industrial consumers buy directly, which means more plants scheduling more often, on shorter notice.<\/p>

Storage is becoming a rulebook of its own.<\/strong> Large-scale battery integration is the answer the sector is giving to curtailment, and it changes the forecasting problem rather than removing it. A battery has to be told what to charge and discharge, block by block, against a forecast of what the plant will produce and of what the grid will accept. Get the minute-scale profile wrong and the battery arbitrages the wrong way.<\/p>\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t

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Rulebook<\/p>\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t

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What it sets<\/p>\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t

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Why it matters to a forecast<\/p>\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t

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Rulebook<\/p>\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t

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What it sets<\/p>\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t

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Why it matters to a forecast<\/p>\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t

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CERC, inter-state<\/p>\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t

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Tolerance band and the trajectory of X<\/p>\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t

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Band halved on 1 April 2026, denominator shrinks from 2027<\/p>\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t

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State commissions<\/p>\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t

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Intra-state bands, charges, revision gates<\/p>\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t

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Gujarat and Rajasthan differ from the central rules<\/p>\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t

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Short Term Open Access<\/p>\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t

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Booked capacity and the schedule against it<\/p>\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t

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More plants scheduling more often, on shorter notice<\/p>\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t

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Key context<\/h3>\t\t\t\t<\/div>\n\t\t\t\t
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This is the structural point.<\/strong> Curtailment, the deviation band, open access and storage dispatch are four different mechanisms, set at four different levels, and they all resolve inside the same 15-minute block. A forecast that is good on a national monthly average answers none of them.<\/p>\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t

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Satellite imagery over the Kachchh region, 31 July 2024 and 17 August 2024. Analysis: CalibSun<\/figcaption>\n\t\t\t\t\t\t\t\t\t\t<\/figure>\n\t\t\t\t\t\t\t\t\t<\/div>\n\t\t
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The monsoon decides when the money is lost<\/h3>\t\t\t\t<\/div>\n\t\t\t\t
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Around 75 percent of the deviation charges an Indian solar plant pays in a year are paid during the monsoon and fog months.<\/p>

The exposure is not annual, it is seasonal, and inside those days it concentrates in a handful of 15-minute blocks. That is why an annual accuracy average tells an operator almost nothing about its bill.<\/p>

From June to September the south-west monsoon carries moisture from the Mascarene High across the Arabian Sea and the Bay of Bengal onto the subcontinent. For a plant in Gujarat or Rajasthan that is not one cloud field. It is two, stacked and moving in opposite directions.<\/p>

CalibSun analysed satellite imagery over the Kachchh region on 31 July 2024 and 17 August 2024, alongside ERA5 wind roses computed at 775, 500 and 300 hPa over 2020 to 2024. The pattern is stable. Fragmented low clouds arrive from the sea on a south-westerly flow and travel north-east. High-altitude layers overlay them, moving east to west.<\/p>

A single cloud-motion vector from satellite imagery collapses that vertical structure into one plane. Geostationary imagery resolves at roughly 15 minutes and 3 km. Below the 15-minute block, that latency is comparable to the whole forecast horizon.<\/p>\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t

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Region<\/p>\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t

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Dominant constraint<\/p>\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t

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Forecasting difficulty<\/p>\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t

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Region<\/p>\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t

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Dominant constraint<\/p>\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t

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Forecasting difficulty<\/p>\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t

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Kachchh and Banaskantha, Gujarat<\/p>\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t

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Monsoon regime, two decoupled cloud layers<\/p>\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t

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Cloud vector methods assume a single advected layer<\/p>\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t

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Bikaner and Jodhpur, Rajasthan<\/p>\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t

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Desert-scale plants, dust and winter fog<\/p>\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t

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Fog days cut output by up to 89 percent<\/p>\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t

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Tamil Nadu and Karnataka<\/p>\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t

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Coastal convection, north-east monsoon<\/p>\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t

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Cells form and dissolve inside one satellite frame<\/p>\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t

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Key context<\/h3>\t\t\t\t<\/div>\n\t\t\t\t
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Indian cloud physics is not mid-latitude cloud physics. Peer-reviewed work on Indian forecasting regulation notes that convective clouds prevalent in India form and dissolve quickly, unlike the mostly advective cloud motion of mid-latitudes. Cloud vector methods assume advection. In a convective monsoon regime the assumption breaks.<\/p>\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t

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Where the gap sits, and why a battery needs it<\/h2>\t\t\t\t<\/div>\n\t\t\t\t
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In an independent benchmark across 30 sites, CalibSun ranked first of seven providers, reducing normalised mean absolute error against the incumbent by 46 percent at 5 minutes, 33 percent at 15 minutes and 23 percent at 60 minutes. Beyond two hours every provider converges on the same weather models and the gap closes.<\/p>

Those two horizons, 5 and 15 minutes, are exactly the ones a battery is dispatched on. A storage asset paired with a solar plant decides charge and discharge against the expected profile of the next few blocks, not against a daily total. It is the horizon where the curtailment can be absorbed instead of lost, and the horizon where the deviation is settled. The place where CalibSun is measurably strongest is the place where storage makes its money.<\/p>\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t

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Horizon<\/p>\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t

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What the market uses today<\/p>\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t

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Where the gap sits<\/p>\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t

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Horizon<\/p>\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t

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What the market uses today<\/p>\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t

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Where the gap sits<\/p>\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t

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Day-ahead<\/p>\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t

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Numerical weather prediction<\/p>\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t

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Adequate at plant level<\/p>\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t

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Intraday, one to four hours<\/p>\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t

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NWP and satellite imagery<\/p>\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t

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Local microclimate not resolved<\/p>\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t

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One minute to one hour<\/p>\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t

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No effective coverage<\/p>\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t

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Cloud motion below satellite resolution<\/p>\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t

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Pre-construction resource<\/p>\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t

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Satellite databases only<\/p>\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t

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No on-site measurement to calibrate<\/p>\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t

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Key context<\/h4>\t\t\t\t<\/div>\n\t\t\t\t
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The revision gate sits close to two hours centrally and close to one hour in Gujarat. That is exactly the window where the measured gap is widest, and it is the window a satellite-only product cannot reach.<\/p>\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t

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CalibSun in India: on-site data where the models stop<\/h2>\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t
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Global satellite models and numerical weather prediction describe the atmosphere in kilometres and in hours. The cloud about to cross a specific array sits below both. CalibSun measures it from the ground.<\/p>\t\t\t\t\t\t\t\t<\/div>\n\t\t

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\n\t\t\t\t\t\t\t\t\t\t\n\t\t\t\t\t\t\n\t\t\t\t\t\t\t\t\tINSTANT | Nowcasting<\/span>\n\t\t\t\t\t<\/span>\n\t\t\t\t\t<\/a>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t
\n\t\t\t\t\t\t\t\t\t\t\n\t\t\t\t\t\t\n\t\t\t\t\t\t\t\t\tNEXT | Forecasting<\/span>\n\t\t\t\t\t<\/span>\n\t\t\t\t\t<\/a>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t
\n\t\t\t\t\t\t\t\t\t\t\n\t\t\t\t\t\t\n\t\t\t\t\t\t\t\t\tFUTURE | Solar resource assessment<\/span>\n\t\t\t\t\t<\/span>\n\t\t\t\t\t<\/a>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t
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INSTANT, sub-hourly nowcasting for monsoon ramps and storage dispatch<\/h3>\t\t\t\t<\/div>\n\t\t\t\t
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INSTANT deploys hemispherical sky imagers and pyranometers on the plant, updates every minute, and anticipates irradiance drops at second to minute resolution. An inner camera triangle covers clouds within 5 km, an outer triangle 5 to 30 km. Because it measures cloud height by stereoscopy rather than assuming it, it separates the two monsoon layers instead of averaging them.<\/p>

That is the signal a co-located battery needs. Knowing a ramp is coming two minutes before it arrives is what allows the storage asset to charge the excess instead of the plant losing it to curtailment.<\/p>

At the Loulo gold mine in Mali, INSTANT has run continuously and unattended since 2020, on a photovoltaic fleet tripled to 72 MWp over a 65 MW heavy fuel oil and diesel grid.<\/p>\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t

\n\t\t\t\t\t\t\t\t\t\t\n\t\t\t\t\t\t\n\t\t\t\t\t\t\n\t\t\t\t<\/path><\/svg>\t\t\t<\/span>\n\t\t\t\t\t\t\t\t\tDiscover more<\/span>\n\t\t\t\t\t<\/span>\n\t\t\t\t\t<\/a>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t
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NEXT, intraday and day-ahead accuracy where deviation is settled<\/h3>\t\t\t\t<\/div>\n\t\t\t\t
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NEXT assimilates plant measurements from your SCADA, satellite imagery and a weather model ensemble, and returns quantile distributions per 15-minute block rather than a single trace, timed to the revision gates. It is software only, delivered by API, with no hardware on site. In an independent 30-site benchmark it ranked first of seven providers.<\/p>\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t

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FUTURE, on-site measurement before the plant exists<\/h3>\t\t\t\t<\/div>\n\t\t\t\t
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FUTURE runs twelve months of on-site measurement at 5-minute resolution to correct satellite bias at source, taking irradiance uncertainty from around 5 percent to 0.5 percent. It produces a bankable typical meteorological year on 20 to 30 years of corrected satellite history, with P50 and P90 structured for lenders, plus a 1-minute series for storage sizing.<\/p>\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t

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Need more information?
Get in touch!<\/h2>\t\t\t\t<\/div>\n\t\t\t\t
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  • \n\t\t\t\t\t\t\t\t\t\t\t\n\t\t\t\t\t\t\t<\/path><\/svg>\t\t\t\t\t\t<\/span>\n\t\t\t\t\t\t\t\t\t\tQuestions<\/span>\n\t\t\t\t\t\t\t\t\t<\/li>\n\t\t\t\t\t\t<\/ul>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t
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    Frequently Asked Questions<\/h2>\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t
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    How much Indian solar capacity is exposed to curtailment? <\/h3><\/span>\n\t\t\t\t\t\t\t\n\t\t\t<\/path><\/svg><\/span>\n\t\t\t<\/path><\/svg><\/span>\n\t\t<\/span>\n\n\t\t\t\t\t\t<\/summary>\n\t\t\t\t
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    Around one third of the renewable capacity recently commissioned faces grid curtailment, 33 percent of 54.8 GW according to ICRA as of May 2026. Under temporary general network access the curtailed share reaches 50 to 60 percent during solar generation hours. It is most pronounced in Rajasthan and Gujarat, the two states building fastest.<\/p>\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t<\/details>\n\t\t\t\t\t\t

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    What deviation band applies to an Indian solar plant in 2026? <\/h3><\/span>\n\t\t\t\t\t\t\t\n\t\t\t<\/path><\/svg><\/span>\n\t\t\t<\/path><\/svg><\/span>\n\t\t<\/span>\n\n\t\t\t\t\t\t<\/summary>\n\t\t\t\t
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    Under the central framework the first volume limit is a deviation up to 5 percent of available capacity from 1 April 2026, against 10 percent until 31 March 2026, and the second runs up to 10 percent. Intra-state sales follow the applicable state regulation, which may differ. The coefficient X begins to fall in 2027, which tightens the same rule further.<\/p>\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t<\/details>\n\t\t\t\t\t\t

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    Why does satellite forecasting underperform during the monsoon? <\/h3><\/span>\n\t\t\t\t\t\t\t\n\t\t\t<\/path><\/svg><\/span>\n\t\t\t<\/path><\/svg><\/span>\n\t\t<\/span>\n\n\t\t\t\t\t\t<\/summary>\n\t\t\t\t
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    Geostationary imagery resolves at roughly 15 minutes and 3 km, and cloud vector methods assume clouds are advected rather than formed and dissolved in place. Monsoon conditions stack two layers moving in different directions, and convective cells appear and disappear inside a single frame interval.<\/p>\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t<\/details>\n\t\t\t\t\t\t

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    What does a battery change for forecasting? <\/h3><\/span>\n\t\t\t\t\t\t\t\n\t\t\t<\/path><\/svg><\/span>\n\t\t\t<\/path><\/svg><\/span>\n\t\t<\/span>\n\n\t\t\t\t\t\t<\/summary>\n\t\t\t\t
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    It moves the problem rather than removing it. A battery has to be told what to charge and discharge for each 15-minute block, against a forecast of plant output and of what the grid will accept. That decision is made at the 5 and 15 minute horizons, which is where the measured accuracy gap is widest.<\/p>\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t<\/details>\n\t\t\t\t\t<\/div>\n\t\t\t\t\t