UPERC Clears 20 MW Floating Solar Project in Gorakhpur

Battery Material Company Astracite Raises $1.3 Million in Investments

RECPDCL Names Winner of 2 GW Transmission Project in Karnataka

Andhra Pradesh Floats Empanelment Tender for Rooftop Solar Projects

CERC Rejects Wind Developer’s Force Majeure Claim in 200 MW SECI Project

MSP Steel to Procure Power from Elevate Solar’s 10 MW Project

KREDL Invites Bids for 450 MW/900 MWh Battery Storage Projects

Mongolia Invites Bids for 110 MW Solar, 188 MWh Storage Systems

BEE Extends Solar Module Star Ratings Until December 31, 2026

Karnataka High Court Quashes KERC’s Captive Status Verification Procedure


					<table id="amazon-polly-audio-table">
						<tr>
						<td id="amazon-polly-audio-tab">
							<div id="amazon-ai-player-label">Listen to this article</div>
							<div id="amazon-ai-player-container">
			<audio class="amazon-ai-player" id="amazon-ai-player" preload="none" controls   controlsList="nodownload" >
				<source type="audio/mpeg" src="https://cms.mercomindia.com/wp-content/uploads/2026/05/amazon_polly_95112.mp3?version=1779274085">
			</audio>
		</div>
							<div id="amazon-polly-subscribe-tab"></div>
							<div id="amazon-polly-by-tab"></div>
						</td>
						</tr>
					</table><p>The Grid Controller of India (<a href="https://grid-india.in/en/" target="_blank" rel="noopener">GRID-India</a>) has flagged a sustained frequency oscillation event in the Bhadla-Bikaner-Fatehgarh renewable energy complex in Rajasthan earlier this month.</p>
<p>The event occurred between 10:26 AM and 10:40 AM on May 11, 2026, during which oscillations in voltage, active power, and reactive power were recorded across seven renewable energy projects with a cumulative capacity of 3,168 MW.</p>
<p>GRID-India has asked these renewable energy developers to conduct a detailed root cause analysis of the oscillation event and submit a report within 15 days.</p>
<p>In a communication to renewable energy developers’ associations, GRID India said that according to an analysis based on phasor measurement unit (PMU) data, the 400 kV bus voltage at the Bhadla substation varied sharply between 373 kV and 440 kV during the event. This severe system-wide oscillation calls for a detailed review by the renewable energy developers and original equipment manufacturers (OEMs).</p>
<p>The preliminary assessment covered the timing of oscillation onset, active and reactive power swings, dissipated energy flow, and the Q-V phase relationship. Certain projects showed early oscillatory response and positive energy-flow characteristics.</p>
<p>Explanations have been sought from the following projects:</p>
<ul>
<li>SJVN Green’s 888 MW project at Bikaner-II</li>
<li>Eden Renewable Alma’s 300 MW project at Bhadla-II</li>
<li>GEPL’s 300 MW project at Bikaner-II</li>
<li>XL Xergi Power’s 400 MW project at Fatehgarh-III</li>
<li>SPCEP’s 300 MW project at Bikaner</li>
<li>Altra Exergi’s 380 MW project at Fatehgarh-III</li>
<li>Ayana’s 600 MW project at Bikaner</li>
</ul>
<p>Developers must specifically examine inverter response, plant controller behavior, power plant controller settings, reactive power and voltage control functions, and any protection or control action that may have occurred during the oscillation period.</p>
<p>They must support their findings with disturbance recorder data, event logger records, protection relay event logs, low-voltage ride-through and high-voltage ride-through activation records, and internal or OEM analyses.</p>
<p>GRID-India also expressed concern about the unavailability of complete PMU data for 24 renewable energy projects totaling 6,751 MW during the event window. PMU data was available for only 71.4% against the target of 100%.</p>
<p>It noted that the lack of PMU data significantly affected post-event analysis and source identification. It directed developers to immediately resolve PMU data availability issues and ensure 100% data availability for future events.</p>
<p>The letter also referred to the root cause analysis reports that remain pending in response to a January 27, 2026, communication seeking data on 15 earlier major oscillation events that had been shared with renewable energy associations and developers.</p>
<p>According to an earlier GRID-India discussion paper, major renewable energy complexes, particularly in Rajasthan, had <a href="https://www.mercomindia.com/grid-india-proposes-grid-forming-capability-for-50-mw-bess-installations" target="_blank" rel="noopener">revealed</a> challenges related to low system strength, altered fault behavior, weak-grid oscillations, and sensitivity of inverter controls.</p>
<p>Subscribe to Mercom’s real-time <a href="https://www.mercomindia.com/product/mercoms-renewable-energy-regulatory-updates" target="_blank" rel="noopener">Regulatory Updates</a> to stay informed about critical updates from the renewable industry.</p>


GRID-India Flags Severe Frequency Oscillation at 3.16 GW Rajasthan RE Complex


					<table id="amazon-polly-audio-table">
						<tr>
						<td id="amazon-polly-audio-tab">
							<div id="amazon-ai-player-label">Listen to this article</div>
							<div id="amazon-ai-player-container">
			<audio class="amazon-ai-player" id="amazon-ai-player" preload="none" controls   controlsList="nodownload" >
				<source type="audio/mpeg" src="https://cms.mercomindia.com/wp-content/uploads/2024/10/amazon_polly_70821.mp3?version=1728911264">
			</audio>
		</div>
							<div id="amazon-polly-subscribe-tab"></div>
							<div id="amazon-polly-by-tab"></div>
						</td>
						</tr>
					</table><p>For three days in August 2024, India&#8217;s electricity grid witnessed persistent high frequency above the ceiling of 50.05 Hz for 26% to 38% of the time.</p>
<p>All three days were Sundays when power demand usually drops. The contributing factors were the over-injection of solar and wind energy, limited flexibility from hydropower stations, and pumped storage plants due to high inflows and high reservoir levels. Inadequate flexibility of intra-state thermal generating stations and under-drawal, insufficient liquidity in the day-ahead and real-time markets (DAM/RTM) in the power exchanges, resulting in states committing more units, also added to the challenges.</p>
<p>A report by the Grid Controller of India said grid frequency remained above the 50.05 Hz limit for 226, 120, and 258 minutes on August 4, 11, and 25, respectively, during solar hours. The maximum instantaneous frequency on these days was 50.39 Hz, 50.33 Hz, and 50.38 Hz, respectively.</p>
<p>On these days, solar penetration as a percentage of the demand at the time of the highest frequency was 19.39%, 21.3%, and 18.45%, respectively.</p>
<p>Similar grid frequency fluctuations were <a href="https://www.mercomindia.com/cerc-reverts-to-frequency-linked-mechanism-as-grid-security-faces-threats" target="_blank" rel="noopener">witnessed</a> in December 2022 when the frequency deviated dangerously from the acceptable range of 49.90 -50.05 Hz, oscillating from 50.5 Hz to 49.41 Hz.</p>
<p>In August this year, the Central Electricity Regulatory Commission <a href="https://www.mercomindia.com/cerc-deviation-settlement-guidelines" target="_blank" rel="noopener">issued</a> regulations related to the deviation settlement mechanism. These regulations seek to ensure that grid users do not deviate from their schedule of drawal and injection of electricity in the interest of the grid&#8217;s security and stability.</p>
<p>The Grid India report said such sustained high-frequency operations threaten grid security. While short-term (real-time, day-ahead, and week-ahead) operational planning can offer only temporary relief, sustainable interventions are needed to manage high frequency in the long term.</p>
<p>Grid India asked all user entities to analyze the events and take measures to ensure the security and reliability of the country&#8217;s power systems.</p>
<p>It reiterated its earlier suggestions to enhance flexibility in grid operations. They include:</p>
<ul>
<li>Reduction in minimum turn-down level of intrastate thermal stations as per CEA regulations</li>
<li>Reduction in minimum turn-down level to 40 % of Maximum Continuous Rating (MCR)</li>
<li>Two-shift operation of selected thermal units with a high energy charge rate</li>
<li>Incentivize flexible operation by notification of compensation for part load operation and start/stops</li>
<li>Implementing a resource adequacy framework</li>
<li>Increase the capacity of long-duration storage</li>
<li>Power market reforms to reduce fragmentation of the market, raise market cap, and introduce negative pricing</li>
<li>Frequency response from renewable energy sources</li>
<li>Curtailment of renewable energy generation as a last resort during sustained high-frequency</li>
</ul>
<p>As per the Indian Electricity Grid Code (IEGC) 2023, the National Reference Frequency is 50.000 Hz, and the allowable frequency band is 49.900 Hz -50.050 Hz. IEGC mandates that the National Load Despatch Center, Regional Load Despatch Center, and State Level Loan Despatch Center endeavor to keep the grid frequency close to 50.000 Hz. If the frequency goes outside the allowable band, they must restore it within the permissible band of 49.900 Hz &#8211; 50.050 Hz as soon as possible.</p>
<p>All grid users must maintain their drawal per schedule to ensure frequency remains within the specified band. On regular days, the frequency remains within the IEGC-specified band for around 75 to 80% of the time.</p>
<p><strong>Drop in Electricity Demand</strong></p>
<p>The Grid India report said a more pronounced reduction in electricity demand was observed after July 31, coinciding with the intensified monsoon activity in the northern states. As a result, electricity demand in August saw a notable decline, fluctuating between 175 GW and 209 GW.</p>
<p><img loading="lazy" decoding="async" class=" wp-image-70824 aligncenter" src="https://mercomindia.s3.ap-south-1.amazonaws.com/wp-content/uploads/2024/10/High-Grid-Frequency-300x214.jpg" alt="High Grid Frequency" width="536" height="382" srcset="https://mercomindia.s3.ap-south-1.amazonaws.com/wp-content/uploads/2024/10/High-Grid-Frequency-300x214.jpg 300w, https://mercomindia.s3.ap-south-1.amazonaws.com/wp-content/uploads/2024/10/High-Grid-Frequency-768x547.jpg 768w, https://mercomindia.s3.ap-south-1.amazonaws.com/wp-content/uploads/2024/10/High-Grid-Frequency-650x463.jpg 650w, https://mercomindia.s3.ap-south-1.amazonaws.com/wp-content/uploads/2024/10/High-Grid-Frequency-624x444.jpg 624w, https://mercomindia.s3.ap-south-1.amazonaws.com/wp-content/uploads/2024/10/High-Grid-Frequency-600x427.jpg 600w, https://mercomindia.s3.ap-south-1.amazonaws.com/wp-content/uploads/2024/10/High-Grid-Frequency.jpg 826w" sizes="auto, (max-width: 536px) 100vw, 536px" /></p>
<p>Solar generation remained consistent and stable throughout this period, with daily peaks around 40 GW. Despite the reduction in overall demand, solar generation continued at its typical levels, creating an oversupply situation during peak solar hours.</p>
<p>Wind generation also remained between 20 GW and 25 GW in the first week of August, tapering to between 10 GW and 18 GW later in the month. The high initial wind output and the gradual decline introduced additional variability into the grid, challenging operators to manage the fluctuating wind supply while balancing it with the steady solar output and increasing hydropower generation.</p>
<p>With a record amount of solar installations <a href="https://www.mercomindia.com/india-15-gw-solar-1h-2024" target="_blank" rel="noopener">projected</a> over the next five years, the frequency of grid-related issues will continue to rise unless battery energy storage is urgently integrated into the system.</p>


High Grid Frequency Events Prompt Grid India to Warn Users to be Cautious


					<table id="amazon-polly-audio-table">
						<tr>
						<td id="amazon-polly-audio-tab">
							<div id="amazon-ai-player-label">Listen to this article</div>
							<div id="amazon-ai-player-container">
			<audio class="amazon-ai-player" id="amazon-ai-player" preload="none" controls   controlsList="nodownload" >
				<source type="audio/mpeg" src="https://cms.mercomindia.com/wp-content/uploads/2023/04/amazon_polly_53011.mp3?version=1781010539">
			</audio>
		</div>
							<div id="amazon-polly-subscribe-tab"></div>
							<div id="amazon-polly-by-tab"></div>
						</td>
						</tr>
					</table><p>The Central Electricity Regulatory Commission (<a href="https://cercind.gov.in/" target="_blank" rel="noopener">CERC</a>) has expanded the scope of operation of the Reserve Regulation Ancillary Services (RRAS) Regulations, 2015, to facilitate the availability of adequate power reserves with the system operator to manage the peak demand.</p>
<p>The aim of the RRAS Regulations 2015 is to restore the frequency at the desired level and to reduce congestion in the transmission network.</p>
<p>The ancillary services ensure generation to meet the excess demand during peak hours.</p>
<p>Expanding the scope of RRAS Regulations, the Central Commission has included state-generating stations whose tariffs have been determined or adopted by the State Commission and are willing to participate in RRAS.</p>
<p>Also, included under the purview of RRAS Regulations are generating stations that have been mandated by the central government to participate in RRAS and have their tariffs discovered through a competitive bidding process.</p>
<p>This is in addition to the regional entities whose tariffs have been determined and adopted by the Central Commission.</p>
<p>Also, the nodal agency’s merit order stack must now encompass state-generating stations whose tariffs have been determined or adopted by the State Commission and generating stations mandated by the central government to participate in RRAS, as well as regional generating stations whose tariffs have been determined and adopted by the Commission.</p>
<p>Under the existing RRAS Regulations 2015, only generating stations that are regional entities with their tariff determined or adopted by the Central Commission are eligible to offer RRAS.</p>
<p>Grid-India reported that this made it difficult to use other projects whose tariffs had yet to be determined or adopted by the Commission for RRAS.</p>
<p>After examining the power supply status across the nation, the Commission noted that on April 18, 2023, the highest level of demand reached 215.9 GW. This is anticipated to escalate even more due to rising temperatures in the coming months.</p>
<p>Grid-India informed the Commission of the steps taken by the system operator to guarantee the dependable operation of the grid.</p>
<p>Furthermore, to ensure that reserves are sufficient, Grid-India requested the Commission to expand the scope of RRAS Regulations 2015 to include resources other than the generating stations regulated by the Central Commission.</p>
<p>Recently, CERC  <a href="https://www.mercomindia.com/measures-reduce-grid-frequency-fluctuations" target="_blank" rel="noopener">issued</a> regulations to limit frequency fluctuations within the operating band in the interest of grid security. The regulator has set the normal rate of charges for deviation for a given time block.</p>
<p>Earlier, CERC had <a href="https://www.mercomindia.com/cerc-new-deviation-guidelines-maintain-grid-security" target="_blank" rel="noopener">issued</a> new guidelines to supplement the Deviation Settlement Mechanism (DSM) Regulations 2022 to maintain grid security. The Commission added a new category of wind-solar generators and introduced charges for DSM. Further, it also hiked monetary incentives for both generators and procurers to maintain the grid frequency between the safe range of 49.95-50.05 Hz.</p>
<p>Subscribe to Mercom&#8217;s real-time <a href="https://mercomindia.com/product/mercoms-renewable-energy-regulatory-updates/" target="_blank" rel="noopener">Regulatory Updates</a> to ensure you don&#8217;t miss any critical updates from the renewable industry.</p>


Regulator Amends Ancillary Services Norms to Meet Peak Power Demand


					<table id="amazon-polly-audio-table">
						<tr>
						<td id="amazon-polly-audio-tab">
							<div id="amazon-ai-player-label">Listen to this article</div>
							<div id="amazon-ai-player-container">
			<audio class="amazon-ai-player" id="amazon-ai-player" preload="none" controls   controlsList="nodownload" >
				<source type="audio/mpeg" src="https://cms.mercomindia.com/wp-content/uploads/2023/02/amazon_polly_49081.mp3?version=1781183952">
			</audio>
		</div>
							<div id="amazon-polly-subscribe-tab"></div>
							<div id="amazon-polly-by-tab"></div>
						</td>
						</tr>
					</table><p>The Central Electricity Regulatory Commission (<a href="https://cercind.gov.in/" target="_blank" rel="noopener">CERC</a>) has issued new guidelines to supplement the Deviation Settlement Mechanism (DSM) Regulations 2022 to maintain grid security.</p>
<p>The Commission has added a new category of wind-solar generators and introduced charges for DSM. Further, it has also hiked monetary incentives for both generators and procurers to maintain the grid frequency between the safe range of 49.95-50.05 Hz.</p>
<p>The Commission said there is an urgent need for the system operator to estimate and procure adequate reserves and deploy them prudently to avoid frequency fluctuations and help maintain grid frequency.</p>
<p>While the market participants adjusted to the new regime, it had become incumbent upon the Commission, given the continued frequency fluctuations, to intervene in the interest of grid security and ensure grid participants help maintain grid frequency.</p>
<p>Last December, CERC had <u><a href="https://mercomindia.com/cerc-reverts-to-frequency-linked-mechanism-as-grid-security-faces-threats/" target="_blank" rel="noopener">reverted</a></u> to a frequency-linked DSM as an interim measure to protect grid stability which had come under pressure for three weeks owing to a change in regulations. The grid frequency had deviated <a href="https://mercomindia.com/explainer-why-new-regulations-made-grid-unstable/" target="_blank" rel="noopener">dangerously</a> away from the acceptable range of 49.90 -50.05 Hz. It oscillated from 50.5 Hz and 49.41 Hz on December 20.</p>
<p><strong>Background</strong></p>
<p>The DSM Regulations 2022 came into force on December 5, 2022, after which wide frequency fluctuations in the grid had occurred. The Commission stipulated certain measures to contain frequency within the operating band.</p>
<p>As directed by the Commission, Grid-India provided weekly operational feedback on the implementation of DSM Regulations, highlighting the high and low-frequency events.</p>
<p>Grid-India noted some improvement in the frequency profile excursions above 50.05 Hz but said the overall frequency profile continued to be a concern.</p>
<p>While the frequency remained within the operative band for ~75-80% of the time before December 5, 2022, it deteriorated to the level of ~54% during December 5-26 before improving to ~60% post after December 26.</p>
<p><strong>Commission’s analysis</strong></p>
<p>The Commission stated that the normal rate of charges for deviations for a time block should be equal to the higher of the weighted average Area Clearing Price (ACP) of the Day-Ahead Market segments of all the power exchanges and the weighted average ACP of the Real-Time Market segments for that time block subject to a ceiling of ₹12 (~$0.145)/kWh.</p>
<p>For a general seller (other than a run of river generating station or a generating station based on municipal solid waste), the deviation charges <a href="https://mercomindia.com/cerc-dsm-regulations/" target="_blank" rel="noopener">remain</a> the same. However, the Commission added two new categories, namely for the wind-solar seller being a generating station based on the wind resource and for the wind-solar seller being a generating station based on solar or a hybrid of wind-solar resources.</p>
<p>The deviation charges payable by a seller under these two new categories are given below:</p>
<p style="text-align: center;"><a href="https://mercomindia.com/wp-content/uploads/2023/02/CERC-DSM-Regulations-3.png"><img loading="lazy" decoding="async" class="alignnone wp-image-49083 size-full" src="https://mercomindia.com/wp-content/uploads/2023/02/CERC-DSM-Regulations-3.png" alt="CERC DSM Regulations-3" width="764" height="457" srcset="https://mercomindia.s3.ap-south-1.amazonaws.com/wp-content/uploads/2023/02/CERC-DSM-Regulations-3.png 764w, https://mercomindia.s3.ap-south-1.amazonaws.com/wp-content/uploads/2023/02/CERC-DSM-Regulations-3-300x179.png 300w, https://mercomindia.s3.ap-south-1.amazonaws.com/wp-content/uploads/2023/02/CERC-DSM-Regulations-3-650x389.png 650w, https://mercomindia.s3.ap-south-1.amazonaws.com/wp-content/uploads/2023/02/CERC-DSM-Regulations-3-624x373.png 624w, https://mercomindia.s3.ap-south-1.amazonaws.com/wp-content/uploads/2023/02/CERC-DSM-Regulations-3-600x359.png 600w" sizes="auto, (max-width: 764px) 100vw, 764px" /></a></p>
<p>The deviation charges in a time block payable by a buyer are given below:</p>
<p style="text-align: center;"><strong><a href="https://mercomindia.com/wp-content/uploads/2023/02/CERC-Deviation-Regulations-4.png"><img loading="lazy" decoding="async" class="alignnone wp-image-49084 size-full" src="https://mercomindia.com/wp-content/uploads/2023/02/CERC-Deviation-Regulations-4.png" alt="CERC Deviation Regulations -4" width="738" height="503" srcset="https://mercomindia.s3.ap-south-1.amazonaws.com/wp-content/uploads/2023/02/CERC-Deviation-Regulations-4.png 738w, https://mercomindia.s3.ap-south-1.amazonaws.com/wp-content/uploads/2023/02/CERC-Deviation-Regulations-4-300x204.png 300w, https://mercomindia.s3.ap-south-1.amazonaws.com/wp-content/uploads/2023/02/CERC-Deviation-Regulations-4-650x443.png 650w, https://mercomindia.s3.ap-south-1.amazonaws.com/wp-content/uploads/2023/02/CERC-Deviation-Regulations-4-624x425.png 624w, https://mercomindia.s3.ap-south-1.amazonaws.com/wp-content/uploads/2023/02/CERC-Deviation-Regulations-4-600x409.png 600w" sizes="auto, (max-width: 738px) 100vw, 738px" /></a></strong></p>
<p><strong>When the frequency is under 49.95 Hz</strong></p>
<p>For frequency less than 49.95 Hz, the general seller (other than an RoR generating station or a generating station based on municipal solid waste) will be paid back for deviation by way of over-injection at 120% of the reference charge rate when the frequency is between 49.90 Hz and 49.95 Hz and at 150% of reference charge rate when the frequency is less than 49.90 Hz.</p>
<p>Further, the general seller (other than an RoR generating station or a generating station based on municipal solid waste) will pay for deviation by way of under-injection at 150% of the reference charge rate or at 120% of the regular rate of charge for deviation, whichever is higher. When the frequency is between 49.90 Hz and 49.95 Hz, the general seller will have to pay 200% of the reference charge rate or 150% of the normal deviation charge, whichever is higher, when the frequency is less than 49.90 Hz.</p>
<p>The buyer will be paid back for deviation by way of under-drawal at 120% of the normal rate of charge for deviation when the frequency is between 49.90 Hz and 49.95 Hz and at 150% of the normal deviation charge when the frequency is less than or equal to 49.90 Hz.</p>
<p>The buyer will pay for deviation by way of over-drawal at 150% of the normal rate of charge for deviation when the frequency is between 49.90 Hz and 49.95 Hz and at 200% of the normal rate of charge for deviation when the frequency is less than or equal to 49.90 Hz.</p>
<p><strong>When the frequency is over 50.03 Hz</strong></p>
<p>The general seller (other than an RoR generating station or a generating station based on municipal solid waste) will be paid back for deviation by way of over-injection at 50% of the reference charge rate when the frequency is between 50.03 Hz and 50.05 Hz. No charges apply when the frequency exceeds 50.05 Hz.</p>
<p>The general seller (other than an RoR generating station or a generating station based on municipal solid waste) will pay for deviation by way of under-injection at 75% of the reference charge rate when the frequency is between 50.03 Hz and 50.05 Hz and at 50% of reference charge rate when the frequency is 50.05 Hz or higher.</p>
<p>The buyer will be paid back for deviation by way of under-drawal at 50% of the normal rate of deviation charge when the frequency is between 50.03 Hz and 50.05 Hz. No charges will apply when the frequency is 50.05 Hz or higher.</p>
<p>The buyer will pay for deviation by way of over-drawal at 75% of the normal rate of charge for deviation when the frequency is between 50.03 Hz and 50.05 Hz. If the frequency exceeds 50.05 Hz, the buyer will not have to pay any charges.</p>
<p>Subscribe to Mercom’s real-time <a href="https://mercomindia.com/product/mercoms-renewable-energy-regulatory-updates/" target="_blank" rel="noopener">Regulatory Updates</a> to ensure you don’t miss any critical updates from the renewable industry.</p>


CERC Issues New Deviation Settlement Guidelines to Maintain Grid Security


					<table id="amazon-polly-audio-table">
						<tr>
						<td id="amazon-polly-audio-tab">
							<div id="amazon-ai-player-label">Listen to this article</div>
							<div id="amazon-ai-player-container">
			<audio class="amazon-ai-player" id="amazon-ai-player" preload="none" controls   controlsList="nodownload" >
				<source type="audio/mpeg" src="https://cms.mercomindia.com/wp-content/uploads/2022/12/amazon_polly_46792.mp3?version=1776947998">
			</audio>
		</div>
							<div id="amazon-polly-subscribe-tab"></div>
							<div id="amazon-polly-by-tab"></div>
						</td>
						</tr>
					</table><p>Less than three weeks after the Central Electricity Regulatory Commission&#8217;s (<a href="https://cercind.gov.in/" target="_blank" rel="noopener">CERC</a>) new regulation de-linked deviation charges and frequency, grid frequency swung wildly and dangerously on December 20, which spooked the power industry and launched a debate on the impact of the regulatory change to the health of the grid.</p>
<p>A significant drop or rise in frequency could lead to a blackout.</p>
<p>Concerned about the security of the grid, the Commission has <a href="https://mercomindia.com/cerc-reverts-to-frequency-linked-mechanism-as-grid-security-faces-threats/" target="_blank" rel="noopener">reverted</a> to a frequency-linked deviation settlement mechanism (DSM) as an interim measure to protect grid stability.</p>
<p>Before the new regulation, maintaining a healthy grid frequency was monetarily productive for all stakeholders. The earlier regulation imposed penalties and incentives on power producers and consumers alike, which ensured that the grid frequency did not fluctuate dangerously.</p>
<p>However, the Commission <a href="https://mercomindia.com/cerc-dsm-regulations/" target="_blank" rel="noopener">revised</a> the deviation settlement mechanism (DSM) framework, which has now linked deviation charges to time-block-wise prices discovered in the day-ahead market (DAM), real-time market, and ancillary services market.</p>
<p>The clear and sharp jump and fall of all India frequencies up to 0.5 Hz can be seen in the chart below.</p>
<p><em><a href="https://mercomindia.com/wp-content/uploads/2022/12/Frequency-profile-for-december-1.png"><img loading="lazy" decoding="async" class="aligncenter wp-image-46818 size-full" src="https://mercomindia.com/wp-content/uploads/2022/12/Frequency-profile-for-december-1.png" alt="Frequency profile for december" width="872" height="477" srcset="https://mercomindia.s3.ap-south-1.amazonaws.com/wp-content/uploads/2022/12/Frequency-profile-for-december-1.png 872w, https://mercomindia.s3.ap-south-1.amazonaws.com/wp-content/uploads/2022/12/Frequency-profile-for-december-1-300x164.png 300w, https://mercomindia.s3.ap-south-1.amazonaws.com/wp-content/uploads/2022/12/Frequency-profile-for-december-1-768x420.png 768w, https://mercomindia.s3.ap-south-1.amazonaws.com/wp-content/uploads/2022/12/Frequency-profile-for-december-1-650x356.png 650w, https://mercomindia.s3.ap-south-1.amazonaws.com/wp-content/uploads/2022/12/Frequency-profile-for-december-1-624x341.png 624w, https://mercomindia.s3.ap-south-1.amazonaws.com/wp-content/uploads/2022/12/Frequency-profile-for-december-1-600x328.png 600w" sizes="auto, (max-width: 872px) 100vw, 872px" /></a>*Permissible frequency range per CERC IEGC Regulation is 49.90 -50.05 Hz</em></p>
<p>A top executive of an energy solution company said, &#8220;When the demand exceeds the generation, the frequency tends to go down. Basically, this can be traced back to the new DSM regulations. The impact of DSM is very high and could change how people are scheduling power.&#8221;</p>
<p>He added that frequency fluctuations could recur, and the Commission must work with Grid-India to ensure grid stability.</p>
<p><strong>Regulator&#8217;s rationale for new mechanism</strong></p>
<p>Arguing for the new mechanism, CERC had said the old system was not a reliable indicator of whether the electricity generation was short or surplus. There is little opportunity to profit from price arbitrage using frequency, it said.</p>
<p>Speaking to Mercom, founder of a top renewable energy management company, said, &#8220;The earlier frequency-linked tariff had a barrier where both generators and buyers had to respond based on grid frequency.&#8221;</p>
<p>For instance, earlier, if a power producer scheduled 1 GW but injected 2 GW into the system, the entity would be penalized for the excess energy based on the frequency. The earlier price signals originated from frequency-linked power tariffs,</p>
<p>&#8220;Stakeholders won&#8217;t bother about frequency, and they&#8217;ll look at other price signals that have nothing to do with frequency. The deviation can be compounded because of the changing regulations,&#8221; another industry source said.</p>
<p>Further, the Commission had based its decision on the introduction of ancillary services, which made the linkage of DSM price to frequency largely redundant. While ancillary services are deployed centrally by the system operator to restore and maintain system frequency closer to 50 Hz, the frequency-linked DSM price is a decentralized tool for controlling frequency.</p>
<p>Another reason cited by CERC was that the discipline in the grid had discouraged power distribution companies from waiting for the high-frequency period to draw power as the prices would dip very low during the period. But with grid frequency being maintained mainly within the recommended band, even the DISCOMs couldn&#8217;t take advantage of the price arbitrage.</p>
<p>However, de-linking the frequency without a transitionary phase has repercussions on the Indian grid.</p>
<p>&#8220;The grid is like a flywheel where the speed will increase if more energy is added. If people are not encouraged to consume more when the speed is high, the frequency will not return. There must be some linkage between deviation and frequency if we want to operate in a loose pool system, or we should move towards the European market design, where everyone must operate at a mandated frequency,&#8221; another source said.</p>
<p><strong>A comparison of frequency trajectories</strong></p>
<p>A comparison of the frequency profile is below, which juxtaposes three different periods. December 1, 2022, to December 20, 2022, vs. November 1, 2022, to November 20, 2022 (to assess the immediate effect of the implementation of the new regulation) and December 1, 2021, to December 20, 2021 (to see the impact of the season)</p>
<p><a href="https://mercomindia.com/wp-content/uploads/2022/12/Frequency-variation-index-4.png"><img loading="lazy" decoding="async" class="aligncenter wp-image-46824 size-full" src="https://mercomindia.com/wp-content/uploads/2022/12/Frequency-variation-index-4.png" alt="Frequency variation index" width="792" height="432" srcset="https://mercomindia.s3.ap-south-1.amazonaws.com/wp-content/uploads/2022/12/Frequency-variation-index-4.png 792w, https://mercomindia.s3.ap-south-1.amazonaws.com/wp-content/uploads/2022/12/Frequency-variation-index-4-300x164.png 300w, https://mercomindia.s3.ap-south-1.amazonaws.com/wp-content/uploads/2022/12/Frequency-variation-index-4-768x419.png 768w, https://mercomindia.s3.ap-south-1.amazonaws.com/wp-content/uploads/2022/12/Frequency-variation-index-4-650x355.png 650w, https://mercomindia.s3.ap-south-1.amazonaws.com/wp-content/uploads/2022/12/Frequency-variation-index-4-624x340.png 624w, https://mercomindia.s3.ap-south-1.amazonaws.com/wp-content/uploads/2022/12/Frequency-variation-index-4-600x327.png 600w" sizes="auto, (max-width: 792px) 100vw, 792px" /></a>The chart clearly shows the impact of regulation in the December 1 to December 20 period compared with other more controlled periods during previous regulations.</p>
<p>CERC reported that the sudden increase in the amount of renewable energy in the power grid could reach up to 50%, which may cause problems with inertia. This would affect the drop in frequency that occurs immediately after a significant disruption (inertial response) and before the primary response takes effect.</p>
<p>While changing the regulations to adapt to market conditions is important, grid security must remain sacrosanct.</p>


Explainer: Why the New Regulations Have Made the Grid Unstable


					<table id="amazon-polly-audio-table">
						<tr>
						<td id="amazon-polly-audio-tab">
							<div id="amazon-ai-player-label">Listen to this article</div>
							<div id="amazon-ai-player-container">
			<audio class="amazon-ai-player" id="amazon-ai-player" preload="none" controls   controlsList="nodownload" >
				<source type="audio/mpeg" src="http://mercomindia.com/wp-content/uploads/2022/12/amazon_polly_46785.mp3?version=1672208778">
			</audio>
		</div>
							<div id="amazon-polly-subscribe-tab"></div>
							<div id="amazon-polly-by-tab"></div>
						</td>
						</tr>
					</table><p>The Central Electricity Regulatory Commission (<a href="https://cercind.gov.in/Regulations/168-SOR-DSM.pdf" target="_blank" rel="noopener">CERC</a>) has reverted to frequency-linked deviation settlement mechanism (DSM) as an interim measure to protect grid stability which has been under pressure over the last three weeks owing to a change in regulations.</p>
<p>The grid frequency deviated <a href="https://mercomindia.com/explainer-why-new-regulations-made-grid-unstable/" target="_blank" rel="noopener">dangerously</a> away from the acceptable range of 49.90 -50.05 Hz. It oscillated from 50.5 Hz and 49.41 Hz on December 20.</p>
<p>The Commission, in its order, inserted provisions of the older mechanism that would override the latest regulations until such time amendments are made in the 2022 regulations.</p>
<p>The commission had <a href="https://mercomindia.com/cerc-dsm-regulations/" target="_blank" rel="noopener">revised</a> the DSM framework to delink frequency and link deviation charges to the prices observed on market platforms in the day-ahead market (DAM), real-time market, and ancillary services market during a particular time slot.</p>
<p>It also directed Grid-India to provide weekly reports on frequency fluctuation causes, primary and automatic gain control responses from generating stations, efforts to obtain and deploy secondary reserve ancillary service (SRAS) and reserves regulation ancillary services (RRAS) to control frequency, and any remedial measures taken.</p>
<p>These new rules will take effect at midnight on December 28, 2022. They will remain in place until further notice from the Commission.</p>
<p>“The normal rate of charges for deviations are now capped at ₹12 (~$0.15)/kWh. The frequency-linked DSM is back &#8211; albeit partially now. The broader question is &#8211; the regulatory provisions are extremely nonlinear for over and under-injections. Sellers and buyers would always strive to reduce the DSM payments. RRAS and SRAS would still be critical to watch out for and would determine how the stakeholders (buyers and sellers) respond to the grid plus ancillary market,” said Vishal Pandya, Cofounder, REConnect Energy.</p>
<p>The Commission’s order noted instances where the frequency has been outside the desired range of 49.90 Hz to 50.05 Hz due to both over-injection and under-drawal occurring at different time slots.</p>
<p>To address this issue, general sellers (except for run-of-river generating stations or generating stations based on municipal solid waste) will not be paid from the deviation and ancillary service pool account for over-injection in time blocks where the system frequency is 50.05 Hz or higher.</p>
<p>Further, the order said that when system frequency falls below 49.90 Hz in a certain time block, the general seller will receive 150% of the reference charge rate for excess injection deviation from the deviation and ancillary service pool account during that time block, regardless of volume limits.</p>
<p>General sellers will pay back to the deviation and ancillary service pool account for any shortfall in energy due to under-injection in any time block at 50% of the reference charge rate.</p>
<p>Buyers will be paid back from the deviation and ancillary service pool account for under-drawal in time blocks where the system frequency is 50.05 Hz or higher.</p>
<p>The deviations are attributed to entities scheduling more energy production or consumption than necessary and capacity shortages during peak times. These issues, along with under-injection by generators and over-withdrawal by distribution companies, have made it difficult to use secondary reserve ancillary services and reserve regulations to manage large frequency fluctuations.</p>
<p>As a result, the system frequency and applicable DSM rates have often remained high, and the system operator has occasionally had to use gas generation based on regasified liquefied natural gas to address capacity shortages for ancillary services.</p>
<p>CERC has capped deviation charges at ₹12 (~$0.15)/kWh due to instances of high charges (nearly ₹ 40 (~$0.48)/kWh) resulting from the use of costly ancillary services. These high charges can discourage over-drawing or under-injecting, but they can also incentivize under-drawing or over-injecting if the deviation charge is linked to the normal rate.</p>
<p>Subscribe to Mercom’s real-time <a href="https://mercomindia.com/product/mercoms-renewable-energy-regulatory-updates/" target="_blank" rel="noopener">Regulatory Updates</a> to ensure you don’t miss any critical updates from the renewable industry.</p>


CERC Reverts to Frequency-Linked Mechanism as Grid Security Faces Threats

<p>The Ministry of New and Renewable Energy (<a href="http://mnre.gov.in/" target="_blank" rel="noopener noreferrer">MNRE</a>) has issued draft guidelines for standards regarding the technical specifications for solar grid-tied inverters. The Ministry has invited comments and inputs from the public and stakeholders by April 30, 2020.</p>
<p>Solar inverters must be tested for safety, efficiency, environmental tests, and grid inter-connection aspects to ensure their quality and reliability. Keeping this in mind, the Ministry has introduced relevant standards covering safety, efficiency, environmental, and islanding prevention measures tests for utility-interconnected photovoltaic inverters.</p>
<p>Further, to make the process of testing simple and consistent, the focus has been laid on developing an inclusive standard for photovoltaic grid-tied inverters for complete performance evaluation for grid-interactive applications for quality and reliability assurance in the Indian conditions.</p>
<p>The draft has laid out a detailed interconnection between technical specifications and requirements along with environmental test specifications. The Ministry said that the purpose of the standards is to lay down the requirements for the interconnection of PV systems and inverters to the utility distribution system.</p>
<p>The standards also provide a test procedure to evaluate utility-interconnected PV power systems that operate in parallel with the utility and for utilizing static non-islanding inverters for the conversion of DC to AC. Islanding is the condition in which a distributed generation system continues to power a location even when grid power is not available. So, an anti-islanding inverter will cease to energize a utility system that is out of its regular operation specifications after a specified amount of time.</p>
<p>The draft added that the MNRE series guidelines should be referred to for selecting the samples from a single family of inverters. In August 2019, the MNRE had <a href="https://mercomindia.com/mnre-approves-series-guidelines-solar-inverters/" target="_blank" rel="noopener noreferrer">approved</a> the series guidelines for grouping solar inverters. These guidelines were for conducting tests in laboratories for the implementation of quality control order that was introduced in 2017. As per the guidelines, the manufacturers will have to submit a declaration about the series of their products while submitting the samples of a particular series for testing.</p>
<p>The draft has proposed routine tests that should be performed by the manufacturer on all inverters, and a test report should be included with each inverter. These tests are:</p>
<ul>
<li>Protection against abnormal voltage</li>
<li>Protection against abnormal frequency</li>
<li>Response to utility recovery</li>
</ul>
<p>These tests assume that the equipment has met the applicable requirements of this standard and may be conducted as a factory test or performed as part of a commissioning test, the draft guidelines added.</p>
<p>For the Harmonic test, the MNRE has suggested shifting from the Institute of Electrical and Electronics Engineers (<a href="https://www.ieee.org/" target="_blank" rel="noopener noreferrer">IEEE</a>) standard to the International Electrotechnical Commission (<a href="https://www.iec.ch/" target="_blank" rel="noopener noreferrer">IEC</a>) standard. Solar PV systems incorporate power electronic interfaces, which generate a level of harmonics. These harmonics have a great influence on the operational efficiency and reliability of the system.</p>
<p>Regarding the grid interconnection test, the draft states that the PV system will not inject DC higher than 0.5% of the continuous maximum rated inverter output current into the utility interface when tested at 25%, 50%, 75%, and 100% of rated output power.</p>
<p>“The requirement is not applicable for an inverter that interconnects through a line frequency isolation transformer located between the output of the inverter and the utility system,” the MNRE added.</p>
<p>Regarding the grid management, the MNRE has suggested that the PV system, which is connected to the low voltage (LV) and medium voltage (MV) lines, will be capable of remaining connected to the grid during low and high voltage conditions.</p>
<p>Previously, Mercom has <a href="https://mercomindia.com/confusion-bis-certification-inverters/" target="_blank" rel="noopener noreferrer">written</a> about the struggles of inverter manufacturers in gaining clarity on the ambiguous BIS certification process. The unavailability of labs, lack of testing facilities and workforce, unreasonable costs of testing, absence of series guidelines, and confusion regarding MNRE notifications were some of the issues that have made the compliance of the order “<em>Solar Photovoltaics Systems, Devices and Component Goods Order 2017”</em> extremely difficult. Through several interviews with inverter suppliers, Mercom <a href="https://mercomindia.com/solar-quality-tests-good-fronius-india-interview/" target="_blank" rel="noopener noreferrer">found</a> out that the cost of BIS certification is also a cause of concern for the inverter suppliers apart from the time-taking process.</p>
<p>In January 2020, the Ministry <a href="https://mercomindia.com/new-deadline-bis-certification-solar-inverters/" target="_blank" rel="noopener noreferrer">issued</a> a notification extending the deadline for the self-certification of solar inverters by six months from December 31, 2019, to June 30, 2020. Realizing the need for quality components in solar projects, the government had mandated that laboratories must conduct the tests for compulsory registration with the Bureau of Indian Standards (BIS) for the implementation of the quality order. Considering various issues related to testing fees, and the lack of test labs available, the industry has been seeking more time for compliance since the introduction of the policy.</p>


frequency

Get the most relevant India solar and clean energy news.

RECENT POSTS