# Fifteen-minute blocks: the clock Indian industrial electricity runs on > Indian electricity markets and most industrial tariffs settle in fifteen-minute blocks, 96 a day. Why that clock, not the monthly bill, decides what green electricity and scheduled load are worth. Canonical: https://joulewise.com/insights/fifteen-minute-blocks Publisher: jouleWise Advisory Services Pvt Ltd, Noida, India · Spain Reviewed: 2026-10-08 Status: company page ## In short An industrial electricity bill arrives once a month with one number on it. The system that produced that number runs on a far shorter clock. Open access scheduling with the state load despatch centre, the day-ahead, green day-ahead and real-time exchange markets, deviation settlement and time-of-day tariffs all work in fifteen-minute blocks — 96 of them a day. A plant that only looks at the monthly total has already made all the decisions that mattered, by default. *Published 2026-10-08 · ergOS · the operating layer* ## The bill is monthly; the price is not An industrial electricity bill arrives once a month with one number on it. The system that produced that number runs on a far shorter clock. Open access scheduling with the state load despatch centre, the day-ahead, green day-ahead and real-time exchange markets, deviation settlement and time-of-day tariffs all work in fifteen-minute blocks — 96 of them a day. A plant that only looks at the monthly total has already made all the decisions that mattered, by default. ## Why green electricity is a block-by-block question A contracted solar or wind plant generates when the resource is there, not when the factory is consuming. Generation only counts towards the plant's renewable share when it lands in a block the plant is drawing in; the rest is spilled or banked on terms the state sets. That is why renewable share is capped by matching rather than by capacity, and why a round-the-clock load tends to stall near 60% on open access alone before storage or a different solar–wind balance moves it further. It is also why a time-of-day tariff and the exchange price can move the value of a kWh by a factor of two inside one day. The illustrative tariff on the ergOS screen runs from ₹6.33 off-peak to ₹10.13 in the evening peak, with open access at ₹4.20 and the exchange somewhere in between depending on the hour. ## What scheduling is worth Some industrial load has slack in when it runs: heat pumps charging a thermal store, chillers charging an ice or chilled-water store, compressors with receivers, grinding with silo headroom. Run flat, that load pays the average price. Scheduled against the block price, with storage to carry the gap, it pays closer to the cheapest blocks. The difference is the energy saving, and it is only as large as the spread between the two prices and the share of load that can actually move. The second half is often larger and quieter. Contract demand is billed monthly, so not starting everything at once — shaving the coincident peak by a few percent — is worth real money every month and needs nothing but knowing what is about to happen. In the studio's default case, 8 GWh a year of movable load with 60% flexibility on a ₹1.50 spread, plus 8% off a 10 MW contract demand at ₹350 per kVA per month, is worth about ₹1.06 crore a year, roughly a quarter of the bill for that load. ## When it is worth nothing Set the flat price and the cheap-block price equal and the energy saving goes to zero. That is a real situation: a flat tariff with no time-of-day structure and no on-site generation. ergOS Studio says so rather than finding a number anyway. In that case the operating layer earns on metering, demand management and the disclosure record, which is why ergOS is sold alongside esgOS rather than as a trading tool. ## What the operating layer actually does ergOS meters electricity, steam, fuel and water every fifteen minutes from the source and the load rather than from the invoice; forecasts generation, load and price 96 blocks ahead; schedules with the SLDC and trades the exchange markets; and dispatches heat pumps and storage against price and the production plan. What it controls directly, what it recommends, and what stays with plant operations is agreed per site. **Try it:** [Value the scheduling in ergOS Studio](https://joulewise.com/studios/ergos) ## Questions and answers **How many settlement blocks are there in a day?** 96. Indian scheduling, exchange markets, deviation settlement and most industrial time-of-day tariffs work in fifteen-minute blocks. **What does load scheduling save?** The spread between the flat price and the cheap blocks on the share of load that can move, plus demand charges avoided by shaving the coincident peak. On a flat tariff with no on-site generation, the energy saving is zero. **Does ergOS take control of the plant?** Only what is agreed. The default is metering, forecasting and scheduling with recommendations; direct dispatch of heat pumps and storage is enabled per site with the plant team. ## Related - [Value the scheduling in ergOS Studio](https://joulewise.com/studios/ergos) - [ergOS](https://joulewise.com/solutions/ergos) - [The journey](https://joulewise.com/decarbonisation) --- jouleWise · https://joulewise.com/ · sales@joulewise.com · +91 84483 22771