The Central Electricity Authority (CEA) has released a report on the ramp rate compliance framework and scheduling methodology for coal-based power plants in the context of flexible operation and increasing renewable energy integration.
The report notes that ramp rate is assessed based on changes in average generation between consecutive 15-minute time blocks, while actual ramping includes boiler response, active ramping and stabilisation phases. Therefore, generating units may need to operate at higher ramp rates to achieve the required average ramp rate. The difference between scheduled and actual generation during ramping may result in deviation settlement mechanism charges, even when units operate within their technical ramping capability. In addition, frequent consecutive ramping and immediate reversal without stabilisation can place additional stress on thermal units. The report recommends operating coal-based plants at minimum technical load of 55 per cent, or phase-wise down to 40 per cent, avoiding consecutive ramping of the same units, and introducing ramping and stabilisation blocks. It also recommends using hydropower, gas power plants, pumped storage plants and battery energy storage systems for fine grid balancing and requisite modifications to the regulatory framework.