Workshop on Hydro Power Development17th September, 2018, Delhi
K V S BabaCMD, POSOCO
Image Credit: NASA
Leverage Hydro Power for Balancing the Renewable and Ensuring Grid Stability
Indian Grid…Large Footprint
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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 – Aug’17
• Guidelines for Development of Wind Power Projects – Oct’16
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
• Guidelines in July 2016 for long term growth of RPOs for non-solar & solar
• 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
Policy Initiatives (1)
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Technical Committee on Large Scale Integration of RE, 2016
• 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
Guidelines on Cross Border Trade of Electricity, 2016
• Facilitating cross border trade of electricity between India & neighbouring countries.
• Aims to promote transparency, consistency and predictability in regulatory approaches across jurisdictions and minimize perceptions of regulatory risks.
• Ensures establishment of a larger footprint suitable for RE integration
• Draft CERC Regulations on Cross Border Trade of Electricity in Feb’17
Policy Initiatives (2)
Web-Link: http://powermin.nic.in/sites/default/files/uploads/Final_Consolidated_Report_RE_Technical_Committee.pdf
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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
• Grid Code – Flexibility in Conventional Generation; 55% minimum for thermal
• 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
• Communication System for inter-State transmission of Electricity
• Transmission Planning
• Pilot Project on 05-Minute Metering and Fast Response Ancillary Services (FRAS)
Other Regulatory Measures at Inter-State Level
• Harmonization at intra-state levels
• Report on SCHEDULING, ACCOUNTING, METERING AND SETTLEMENT OF TRANSACTIONS IN ELECTRICITY (“SAMAST”)
Forum of Regulators - Model Regulations on Imbalance Handling Mechanisms
Regulatory Interventions
• Balancing with Conventional Generation
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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
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Balancing of Renewables
• 96,524 MW Pumped Storage potential
• 4785 MW developed• 1080 MW under construction.
• Only four (4) plants of 2450 MW operational as pumped storage.
• Tehri Pumped Storage Plant -First PSP in India to have Variable speed vertical Francis type reversible Turbine. Anticipated to be operational in 2019.
Ancillary Services - Essential Reliability Service
• Layer of Centralized Ancillary Despatch over Decentralized Layer of Scheduling Process
• Ramp Management, Congestion Management
• Grid Resilience, Reliability Support
• Benefits – Generators & State Utilities
• Freedom and Choice available to states retained
• Improvement in Frequency Profile
Enabler – 24x7 Power for All
• Service Providers: 55 Nos.
• Capacity under RRAS: 56 GW
• Instructions/day (Avg.): 7-8 Nos.
• Highest Regulation ‘Up’ in a day: 3816 MW
• Highest Regulation ‘Down’ in a day: 2518 MW
• Weekly Accounting
Weblink: https://posoco.in/download/half-year-
feedback-to-cerc/?wpdmdl=8916
Launched in Apr’16
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Improved Frequency Profile
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Flexibility Resources for Grid Operation to manage variability of demand & RE generation:
- Flexible Hydro / Gas generation
- Grid level Energy Storage (like PSP)
Hourly Variation in Demand (2008-17)
The envelope is likely to widen further due to changes in load pattern
Variation in Demand
6/12/2017 10
Typical Winter Day (2016)Typical Summer Day (2017)
Need for Flexibility Resources
Variation in Hydro Generation
• Sub optimal operation of some hydro generators
– Scope for optimization & flexible operation along with economic gains
– Requirement of flexibility in view of large scale Renewable Integration
• Hydro Power - a source of flexibility & reliability• Overload capability• Fast ramping• Peaking support• Voltage Regulation• Black Start Capability
• Constitution of FOLD Working Group
Need for Optimization of Hydro Resources
• Hydropower potential - 150 GW out of which 44.6 GW (30%) tapped.
• Central – 15 GW, State - 27 GW, Private - 3 GW
• Capacity harnessed for peaking is of the order of 30-32 GW.
Survey of hydro power stations
• 35 GW (79%) out of 44.5 GW
• 149 hydro stations
• 486 generating units
Consultation with hydrogenerators / State LoadDespatch Centres• Appreciation of constraints• Philosophy of dispatch
Big Data Analysis• 9 Years Data Analysis• 38 Million Data Points• Data Visualization
Brain Storming in FOLDMeetings• 6 months work• Around 50 Contributors• More than 1000 man hours
Survey and Analysis Process
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Distribution of Hydro Stations
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Out of the 486number of hydro units responded, there are 146 number of grid friendly peltonturbine hydro units (~8534 MW) which can smoothly operate at part load & regulate generation from no load to full load to provide flexibility in grid operation;
Distribution of Turbine Types
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Region
Multi-Purpose HEPs Electricity-Only HEPs
Number of
Stations
Number
of Units
Capacity
(MW)
Number
of
Stations
Number of
Units
Capacity
(MW)
ER 7 34 2966 3 12 1782
NER 3 8 220 12 31 1042
NR 17 62 6540 31 92 5679
SR 48 148 9821 0 0 0
WR 22 82 6501 6 17 697
All India97 334 26048 52 152 9200
Out of the 149 stations responded, 97 are multipurpose (26048 MW) projects whereas 52 stations (9200 MW) are used purely for electricity generation;
Multi-Purpose/Electricity-Only HEPs
1. Introduction 2. Existing Hydro & Pattern Analysis
& Survey3. Flexibility Metrics 4. Valuing Hydro: Flexibility
Assessment, Ranking & Optimization
5. Pump Storage Facilities6. Constraints in Hydro Generation
Despatch7. Tariff Structure for Hydro Power 8. Scheduling & Dispatch at
Regional level9. International Experience on
Hydro Despatch10. Recommendations11. Bibliography
(Appendices)
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Report on Operational Analysis for Optimization of Hydro Resources & facilitating Renewable Integration in India
1. Peaking Capability
2. Ramping Capability
3. Frequency Response
4. Part-load operation for maintaining reserves,
5. Load following – Correlation with Demand
6. Energy Storage capability (pumped storage hydro units)
7. Multiple start-stop operation
8. Dynamic VAR support - Synchronous condenser operation
9. Black-start capability
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Flexibility Metrics
• Defining Flexibility Indices– Peaking,Ramping,Capacity Utilization
– Flexibility Indices as a metric forimprovement
– Plants with multi part tariff performing better
• Operational Performance– Peak Hydro Support 30 GW in high
hydro season & 18-20 GW in lean hydroseason against IC of 45 GW
– Seasonal Hydro Flexibility
– 87 tested for black start
– 25 Stations out of 150 havesynchronous condenser facility - to beharnessed
Summary of Findings (1)
• Valuing Hydro
– 128 BU of annual hydro generation
– 32 BU Reservoir energy content
– Economic gains with further optimization
• Optimization based on Production CostModelling
– 4 GW Extra Peaking Support duringpeak
– 5 GW Extra Backing down during offpeak
– Overall flexibility enhanced
All India Hydro Gen. Optimisation (with PLEXOS) for a year
Summary of Findings (2)
Sample IllustrationPeaking Support from Hydro Power Stations
• Pilot Project on 05-Minute Scheduling, Metering, Accounting and Settlement for Thermal/Hydro, and on Hydro as Fast Response Ancillary Services (FRAS)
– CERC Order in Petition No. 07/SM/2018 (Suo-Motu) dtd. 16 July 2018
• Covering all Central sector hydro generating stations
– All constraints declared by the hydro stations shall be honoured
– Total energy delivered over the day shall be maintained as declared
– Total energy dispatched under FRAS shall be squared off by end of day
– FRAS shall be triggered based on a stack prepared based on the balance energy available in the hydro station.
– Schedules of the beneficiaries shall not be disturbed in FRAS despatch
– RPCs shall issue weekly FRAS accounts along with the RRAS accounts
– Incentive shall be paid from the DSM Pool on mileage basis 22
Pilot Project – Fast Response Ancillary Services
Optimization & Incentives for Flexibility
Ancillary Services from hydro power stations
Coordinated Scheduling & Despatch
Transmission planning -hydro flexibility
Multi Part TariffSilt Forecasting &
Coordinated Flushing
Inflow Forecasting Review of standards
Revisiting Hydrological Constraints
Renovation & Modernization
Key Recommendations