MERC Forecasting Scheduling Deviation Settlement

The Maharashtra Electricity Regulatory Commission (MERC) is preparing draft regulations for the forecasting, scheduling, and deviation settlement of solar and wind generation in the state. It noted that the process for drafting these regulations was already underway in its response to a petition by the Maharashtra State Electricity Distribution Co. Ltd. (MSEDCL).

The draft regulations are in response to issues that could arise like back-down of solar and wind power from the expected challenges due to expansion of intermittent solar and wind generation in Maharashtra.
According to the Maharashtra Energy Development Agency (MEDA), the state is home to approximately 5 GW of wind and solar installations (solar accounted for about 800 MW) with renewable installations targeted to reach 22 GW by 2022 based on Renewable Purchase Obligation (RPO) requirements set by Ministry of New and Renewable Energy (MNRE).

MERCThe Petition

In its petition, MSEDCL stated that the intermittent nature of wind power and its variable generation in a given period of time creates challenges for maintaining grid stability and for planning power purchases. Forecasting and scheduling helps grid operators operate generators more efficiently to accommodate changes in wind and solar generation. Depending upon the generation, MSEDCL can plan its resources in advance so that its financial burden can be reduced.

MSEDCL asked MERC to provide suitable, state-level guidelines for the scheduling and forecasting of wind and solar power in view of the Model Regulations by the Forum of Regulators on the Forecasting and Scheduling of wind and solar generating stations at the state level.

MSEDCL also asked MERC to initiate a consultative process to frame appropriate regulations for the forecasting and scheduling of wind and solar power at the Intra-State level in Maharashtra.

The MERC Order

MERC held a hearing on August 3, 2017. At the hearing, MERC observed that it has already initiated a process to frame the necessary regulations for the forecasting and scheduling of wind and solar generation, and disposed of the petition by MSEDCL.

MERC also pointed to rules already set forth by the Central Electricity Regulatory Commission (CERC) in its Deviation Settlement Mechanism and Related Matters (Third Amendment) Regulations, 2016. In those rules, CERC set the deviation limit for renewable energy-rich states at 250 MW per time block and the limit for the over-withdrawal or under-withdrawal of renewable energy at not more than 12 percent or 150 MW when grid frequency ranges from 49.70 Hz to 50.10 Hz. This standard will be applied in Maharashtra.

The state-level guidelines are expected to smoothen the renewable generation integration in the state. The order is expected to provide clarity to MSEDCL, which is one of the largest distribution companies in India and caters to the power needs of millions. Once implemented the new regulations are expected to lessen the uncertainty and prevent back-down of solar and wind power which enjoy ‘must run’ status per CERC guidelines.

With approximately 10 GW of solar power expected to be installed in 2017 grid issues have popped up all over the country. Two other states recently issued regulations regarding forecasting and deviation settlement which gives a good template as to what we can expect from Maharashtra.

Andhra Pradesh Electricity Regulatory Commission (APERC) released new regulations for forecasting, scheduling, and deviation settlement of solar and wind generation with immediate effect in August to facilitate large-scale grid integration of solar and wind power while maintaining grid stability.

The Gujarat Electricity Regulatory Commission (GERC) also issued draft regulations for large-scale grid integration of solar and wind power while maintaining grid stability through forecasting, scheduling, and implementing a commercial mechanism for deviation settlement of the generators.