Grid Integration of Renewables

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K V S Baba CEO, POSOCO

kvsbaba@posoco.in

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NR

WR

SR

ER

NER

Ennore

Kudankulam

Kayamkulam

Partabpur

Talcher/Ib Valley

Vindhyachal

Korba

LEGEND

Coal

Hydro

Lignite

Coastal

Nuclear

Vizag

Simhadri

Kaiga

Tarapur

Mangalore

Krishnapatnam

RAPP

SIKKIM

MYANM

MAR

CHICKEN NECK

Cuddalore

SRI LANKACOLOMBO

NEPALBHUTAN

DESHBANGLA

South Madras

Pipavav

Generation Load-Centre

Kolkata

Bhubaneswar

Patna

Lucknow

Delhi

Mumbai

Chennai

Bangalore

Bhopal

Guwahati

Jammu

Ludhiana

Jaipur

Gandhinagar

Indore

Raipur

Thiruvananthapuram

Kozhikode

Hyderabad

Coal

Hydro

Wind and Solar

Courtesy: NASA

Indian Power System

• Peak Demand ~ 160 GW

• Energy Met ~ 3.5 BUs/day

• Hydro Gen. ~ 712 MU/day (Max.)

• Wind Gen. ~ 310 MU/day (Max.)

• Generating Stations ~ 900 Nos.

• Generating Units ~ 2200 Nos.

• > 7000 Sub-stations,

• > 3100 transformers

• 10 Nos. HVDC Bi-pole/BtB

• > 100 nos. 765 kV lines

• > 1300 nos. 400 kV lines,

• > 3200 nos. 220 kV lines

• 26 ISTS transmission licensees

Indian Power Market

• Licensed Traders - 43 Nos.

• Market Participants > 3000 Nos.

• Two Power Exchanges (PXs)

• Indian Energy Exchange

• Power Exchange of India Ltd.

• Open Access Volumes

• Transactions ~ 45,000 Nos./yr.

• Bilateral ~ 14,000 Nos.

• Collective (PX) ~ 31,000 Nos.

• Energy ~ 100 BUs/yr.

• Bilateral ~ 65 BUs

• Collective (PX) ~ 35 BUs

• Short Term ~ 10 %

Nepal Bhutan

Bangladesh

Myanmar

International Interconnections

Indian Grid…Large Footprint

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Wind Potential ~ 100 GW (at 80 m hub- height)

Solar Potential ~ 750 GW (4-7 kWh per sq. m per day)

National Offshore Wind Energy Policy

Solar Cities~ 60 Nos. Green Energy Corridors

Renewables CAGR ~ 18 %

Installed RE Capacity – 57, 260 MW as on 31 Mar’17

Generation-based Incentives

34 Solar Parks – 20 GW

Solar RPO ~ 8 % of total generation by 2022 (Excluding

Hydro)

Solar PV Reverse Bidding ~ Rs. 2.97/kWhr

Accelerated Depreciation

Wind Atlas, 2015

Renewables on the Rise…MW to GW

Intra-State Settlement System and Imbalance

Handling

Forecasting (Load/ RE generation/Net Load)

Spinning Reserves

Frequency Control (Primary/Secondary/

Tertiary)

Technical Standards for RE Generation

Ancillary Services

Balanced Portfolio Flexibility - Harnessing

and Incentivizing Market Design Enhancements

Communication in Power Sector

Capacity Building of all stakeholders

Web-Link: http://powermin.nic.in/sites/default/files/uploads/Final_Consolidated_Report_RE_Technical_Committee.pdf

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Technical Committee on Large Scale Integration of Renewables

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Indian Electricity Act, 2003

• Development of Grid Interactive Renewable Power

• Tariff Determination , Renewable Purchase Obligation

• Grid Connectivity, Market Development

National Electricity Policy, 2005

• Competition and Development of RE technologies

• Policy for Repowering of the Wind Power Projects – Aug’16

• Competitive Bidding

• Guidelines for Grid connected solar PV power projects – Sep’16

• RE Consumption Targets

Tariff Policy, 2016

• Competitive bidding for RE procurement (maximum 35% of installed capacity can be sourced from determined/preferential tariff)

• Renewable Generation Obligations (RGO), Long term RPO

• Vintage and technology multiplier allowed in REC

• Inter-state transmission charges waived off for RE power

• Solar RPO to be 8% by 2022 (excluding hydro power)

• Provisions regarding micro-grids

• Smart meters mandated - consumers 500 units (2017) & 200 units (2019)

• Procurement of power from waste-to-energy plants compulsory

175 GW by 2022

Policy Initiatives

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• Deviation charges of RE generators delinked from frequency

• More opportunities to revise the schedule – 16 times in a day

• Commercial liability known upfront with no additional charges & surcharges

• Centralized (LDCs) & De-centralized (Generators, Aggregators) Forecasting

• Renewable Energy Certificates (RECs) to ensure physical energy balance

Framework for Forecasting, Scheduling & Imbalance Handling for Renewable Energy Generators at Inter-State Level

• Indian Electricity Grid Code – Flexibility in Conventional Generation notified in May’17

• Deviation Settlement Mechanism – Provisions for Renewable Rich states

• Renewable Energy Certificate (REC) Mechanism

• 15 Minute Bidding in Power Exchanges, 24x7 Round-the-clock session

• Ancillary Services Operations, Roadmap to Operationalize Reserves

• Draft Communication System for inter-State transmission of electricity Regulations

• Draft Transmission Planning Regulations, 2017

Other Regulatory Measures at Inter-State Level

• Harmonization at intra-state levels - Draft by Gujarat, Andhra Pradesh, MP, Rajasthan, Odisha, Karnataka, Jharkhand, Tamil Nadu, Chhattisgarh, Manipur & Mizoram. Karnataka notified final regulations in May’16.

• Report on SCHEDULING, ACCOUNTING, METERING AND SETTLEMENT OF TRANSACTIONS IN ELECTRICITY (“SAMAST”)

• FOR Model Regulations in March 2017 regarding Deviation Settlement Mechansim at intra-state level for adoption by respective SERCs.

FOR - Model Regulations on Forecasting, Scheduling and Deviation Settlement of Wind/Solar at the State Level

Regulatory Interventions

• Technical Minimum @ 55 % in Conventional Thermal Generators

• Station Heat Rate (SHR) linked compensation mechanism

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Expected All India Duck Curve

(Sample: 20000 MW of Solar Generation)

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Net Load

Actual Demand

Belly:

Decrease in net load

Neck:

Steep ramping

Head:

Evening Peak

Source: NLDC SCADA data, CAGR assumed: 8%

Max. PLF ~ 78 % (2009-

10)

PLF ~ 62 % (2015-16)

Challenges • Recognize Flexibility • Define Flexibility • Design Metrics for Flexibility • Measure Flexibility • Pay for Flexibility • Incentivize Flexibility

Incentivizing Flexibility

• Operational Pumped Storage Hydro Plants – Purulia (900 MW)

– Srisailam (900 MW)

– Kadamparai (400 MW)

– Ghatghar (250 MW)

– Bhira (150 MW)

• Balancing with Conventional Generation

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1-Apr 1-May 1-Jun 1-Jul 1-Aug 1-Sep

In M

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on U

nits

Flexing the Hydro for Balancing the wind generation in Karnataka

Hydro

Wind

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Flexing of Thermal for Balancing Wind Generation in Karnataka

THERMAL

Wind

Flexing Hydro Flexing Thermal

• Balancing with Pumped Storage Hydro Plant

MW

Kadamparai - Pump Storage Plant 8

Balancing of Renewables

• Load Forecasting; a paradigm shift

• RE forecasting at infancy

• Need for forecasting and scheduling framework at intra state level

• Need for aggregators

• Forecast Service Providers (FSPs)

• Centralized and decentralized

• Capacity Building

2016 pre-Diwali festival

India to prepare for 26th Dec 2019 and 21st June 2020 solar eclipse!! 9

Forecasting & Scheduling

• Layer of Centralized Ancillary Despatch over Decentralized Layer of Scheduling Process

• Ramp Management, Congestion Management

• Grid Resilience, Reliability Support

• Benefits to stakeholders – Generators & State Utilities

• Freedom and Choice available to states retained

• Improvement in Frequency Profile

Enabler – 24x7 Power for All

• RRAS Providers: 48 Nos.

• Capacity under RRAS: 52 GW

• RRAS Instructions (Avg.): 05 to 06 Nos./day

• Highest RRAS ‘Up’ in a day: 3746 MW

• Highest RRAS ‘Down’ in a day: 1946 MW

• Energy Despatch/day- Up : 6 MU, Down : 1 MU

• Weekly Accounting

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Ancillary Services – Security, Reliability and Economy

Primary

• All India - 4000 MW

• Outage of Ultra Mega Power Plant (UMPP) or any similar event

Secondary

• All India - 3623 MW

• NR – 800 MW

• WR – 800 MW

• SR – 1000 MW

• ER – 660 MW

• NER – 363 MW

Tertiary

• All India - 5218 MW

• NR – 1658 MW

• WR – 1353 MW

• SR – 1343 MW

• ER – 857 MW

• NER – 65 MW

• CERC Roadmap for Reserves • Stakeholder Consultations • Pilot project initiated– Sept.’16

• Coal fired based station – NTPC Dadri • Plant level specifications - AGC signals • Control actions from NLDC

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Roadmap for Reserves

• Low Voltage Ride Through (LVRT)

• High Voltage Ride Through (HVRT)

• Voltage and current harmonics

• Primary Response

• Voltage Control

Draft Standards up for public comments http://cea.nic.in/reports/regulation/draft_technical_std_grid_regulations.pdf

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Technical Standards for Grid Connectivity

Imperatives for moving to ‘Fast Markets’

• Learning from implementation of Ancillary Services • Requirements under ancillary despatch are

• Quick / Fast response & turnaround time • Despatch for short durations • Example: hour boundary changeover

• A costly resource, to be used in limited manner for system reliability • Increasing granularity would optimize cost of despatch

• Earliest possible implementation of RRAS despatch instruction is 16 minutes

• Re-scheduling of resources • 4-blocks of 5 minutes (20 min) vs 4-blocks of 15-minutes (60 min)

• Increasing RE penetration

• Ramping requirements

• Recognizing flexibility as a requirement

• Implementation of Primary, Secondary (AGC) and Tertiary Reserves/Control

• Reserves: Despatch, accounting & settlement

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Actions Needed for implementation of Fast Markets in India

• Forecasting

• Scheduling & Despatch

• Markets : 5-minute bilateral markets; Power Exchanges – 5 minute price discovery

• Deviation Settlement 5-minute prices in DSM

• Commercial interface metering

• Settlement system – energy accounting, financial settlement

• Changes in various CERC/SERC Regulations

• Gate closure provisions

• Changes in CEA Metering Standards

• Replacement of meters

• Software upgrade at the RLDCs/SLDCs – scheduling, meter data processing, accounting, settlement

• Software upgrade at the RPCs

• Holding workshops, dissemination, stakeholder capacity building

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Discussion

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Thank You !