Presentation is loading. Please wait.

Presentation is loading. Please wait.

Integration of Renewable Energy

Similar presentations


Presentation on theme: "Integration of Renewable Energy"— Presentation transcript:

1 Integration of Renewable Energy
P.R.Raghuram GM, SRLDC

2 Outline of this presentation
Introduction Basics of Renewable Technologies Scenario of Renewable Energy generation in India Issues involved in Grid Integration of RE: International Experience The Road ahead

3 Outline of this presentation
Introduction Basics of Renewable Technologies Scenario of Renewable Energy generation in India Issues involved in Grid Integration of RE: International Experience The Road ahead

4 The future depends on what we do in the Present….Mahathma Gandhi

5 Drivers for Alternate energy sources
Oil crisis in 1970s Dwindling/ limited natural Resources (Oil, Coal) Energy Security International mandate for development of CDM technologies and to reduce Carbon/ Sulpher/ Green House Gas emissions, phase out fossil fuel generation and develop alternate Energy sources IPCC (Intergovernmental Panel for Climate Change) under UNEP(1998) UNFCCC Rio De Janeiro 1992 Kyoto protocol 1997 Copenhagen Summit 2009 Indian initiatives NAPCC (National Action Plan for Climate Change) JNNSM (Jawaharlal Nehru National Solar Mission)

6 Outline of this presentation
Introduction Basics of Renewable Technologies Scenario of Renewable Energy generation in India Issues involved in Grid Integration of RE: International Experience The Road ahead

7 Various types of Renewable Energy
Wind On shore Off shore Solar Solar PV (Photo Voltaic, Concentrated PhotoVoltaic) Solar Thermal (Solar Concentrated, Parabolic trough/dish, Fresnel collector, Heliostat & Solar Tower receiver, Solar updraft receiver) Micro Hydel (upto 25 MW) Biomass/ Bagasse (the dry fibrous waste that is left after sugarcane has been processed) rice husk, cotton stalk, mustard stalk, groundnut shell, coconut fronds, waste cotton stalks, bark, roots of trees, cane trash, arecanut shells, Prosopis juliflora, poultry litter) Co-generation Municipal Solid waste Geo-Thermal Hydro kinetics Tidal power Wave technology

8 Power vs Wind speed for a typical Induction type WTG
where ρ= wind density, Cp is Power Co-efficient of Wind Turbine, λ is tip speed ratio, θ is the blade pitch angle, Ar = area of wind incidence on blades, v= wind speed Source:

9 Fixed Speed/ Induction type Wind Turbine Generator

10 Variable Speed type Wind Turbine Generator

11 Types of Wind Generators [1, 2, 3, 4]
Squirrel Cage Doubly Fed Direct Drive Induction Induction Synchronous Simple and Robust Less mechanical stress Less mechanical stress Less expensive Less noisy Less noisy Electrically efficient Aerodynamically efficient Aerodynamically efficient Standard generator Standard generator No gearbox Small converter Aerodynamically less Electrically less efficient Electrically less efficient efficient Gearbox included Gearbox included Large converter Mechanical stress Expensive Expensive Noisy Complex, heavy and large generator Oct. 2006 CREDP - Wind Farm Operation and Grid Integration 10

12 Electrical Characteristics of WTG
Reactive requirement: Fault Ride Through (FRT) /Low Voltage ride-through (LVRT) Governor operation available in WTG? Inertia contribution to Grid? Short circuit contribution Can WTG be Black Started? Distributed Generation Systems reduce burden on Tranasmission system and reduce Losses

13 Increase in capacity and efficiency: Development of turbine technology
appr.20,00,000 kWh 160 m Increase in capacity In a mere 20 years, the yield Of wind turbines has increased 100-fold.With the new 6 MW Turbines, It will multiply another fivefold. 2010 6.000 kW 170 m 13

14 Criteria for Site Selection
SITE SELECTION – PLAIN TERRAINS SITE SELECTION – HILLY TERRAINS High annual average Wind Speed ( > 7 m/sec.) Wind Structure at The Proposed Site Altitude of the proposed site. Nature of Ground (soil for proper foundation / civil work ). Favorable environmental condition to prevent corrosion & not prone to cyclone. Availability of electrical infrastructure for evacuation of electricity generated . 2.5 D

15 CSP - TOWER TECHNOLOGY CSP - TROUGH TECHNOLOGY CSP - DISH TECHNOLOGY

16 Typical arrangement of an Small Hydro Power station
SHP station on a river SHP station on a canal

17 Outline of this presentation
Introduction Basics of Renewable Technologies Scenario of Renewable Energy generation in India Issues involved in Grid Integration of RE: International Experience The Road ahead

18 WIND ENERGY HARNESSED Source : MNRE
SR Maximum Wind AT 18:59 HRS % of Wind in SR I/C – 17% % of Wind Gen in SR Demand Met – 14.9 % % of Wind in TN I/C – % % of Wind Gen in TN Demand % Capacities in MW as on Inst. Cap. Potential Wind Power 13066 48561 Small Hydro Power 2939 14292 Biomass Power 997 8680 Bagasse Cogeneration 1562 5000 Waste to Power (Urban & Industrial ) 72 7000 Solar Power (SPV) 18 200000 Total 18654 283533 WIND ENERGY HARNESSED Source : MNRE 18

19 Wind Power Potential 19

20 Map showing Solar radiation across India
20

21 Potential Capacity of RE Sources Statewise
Wind SHP Biomass Andhra Pradesh 8968 552 830 Arunchal Pradesh 1333 Chattisgarh Gujarat 10645 916 Haryana 110 Himachal Pradesh 2268 Jammu & Kashmir 1411 Karnataka 11531 643 859 Kerala 1171 Maharashtra 4584 762 1711 Madhra Pradesh 1019 400 1059 Nagaland 28.67 Punjab 390 Rajasthan 4858 63 1289 Tamilnadu 5530 1186 Uttaranchal 1609 West Bengal 450 Total 48756 8680 21

22 Both Solar and wind concentration are geographically same
Solar Map Wind Map Both Solar and wind concentration are geographically same 22

23 Diurnal patterns S-W monsoon N-E monsoon Seasonal patterns

24 Integration issues of Wind

25 Integration issues of Wind
Planning criterion for RE Variability and Intermittancy Forecasting and Scheduling SCADA / telemetry Network related Problems and Congestion Protection Commercial mechanism implementation

26 Planning Transmission system for RE
Initially wind as an energy rather than capacity addition As the penetration of the wind increases, Wind treated interms of MW capacity Network development and O&M upto the pooling station by the wind developer beyond the pooling station by the Distribution licensee N-1 criterion to be maintained

27 Planning Transmission system for RE
Criteria used for Tr. Planning of Conventional power to be upgraded for RE Studies for power flow, time-domain and small-signal stability along with short-circuit duty analyses tools Trade off between network optimal utilization and redundancy Dynamic Line Rating : During high wind periods the network can be loaded to a higher levels of thermal ratings of the network because of higher heat dissipation due to wind. This concept is called dynamic Line rating. Diversity Factor : Wind farms are usually located across large geographical spreads, hence wind pattern for all the wind mills and wind farms is not the same, thus the wind production at a given point of time is not same for all the wind generators and farms. This is called Diversity factor and is to be duly factored while designing evacuation systems.

28 Planning criterion for RE
Outage of wind generator should be planned during lean wind season, outage of solar, if required during the rainy season and outage of run-of-the-via hydro power plant in the lean water season. 50Hz Load Generation Time frame Planning criterion 1 -30 years transmission and resource adequacy assessments. 1 year- 1 month New capacity addition, Tr. Adequacy assessment 1 day- 1 week Wind forecast, Demand forecast, Congestion monitoring, Market operations, Minutes - hour Wind forecast, Demand forecast, Unit Commitment and L-G balance Seconds-to-minutes Protection, AGC, Governor, Excitations systems, PSS, AVRs, SPS, FRT capability

29

30 Integration issues of Wind
Planning criterion for RE Variability and Intermittancy Forecasting and Scheduling SCADA / telemetry Network related Problems and Congestion Protection Commercial mechanism implementation

31 TN WIND GENERATION (28% of Energy)
Intermittancy: not continuously available Variability : variable in magnitude Uncertainity : Variations may not be as Expected SR Maximum Wind AT 18:59 HRS % of Wind in SR I/C – 17% % of Wind Gen in SR Demand Met – 14.9 % % of Wind in TN I/C – % % of Wind Gen in TN Demand % TIME → Data taken from SCADA 31 31 31

32 KARNATAKA WIND GENERATION
Karnataka can better manage variability due to Hydro as penetration increases, Difficult to manage TIME → Data taken from SCADA 32 32 32

33 TN WIND GENERATION MUs Data are as received from TN 33 33 33

34 Impact of Variability on Home state
Wind generation typically varies from 800 to 2000 MWs. Increased requirement of spinning reserve Dip the system frequency due to absence of spinning reserve Increasing the spot market cost of power Host state having to resort to massive load shedding Additional costs of dispatch of Liquid generation to offset the drop in RE generation Any committed export through bilateral open access contracts can not be revised adding to the voes of the host state. Burden of Frequency Support Ancillary services Sudden Increase in RE generation- Thermal Gen backing down has limitations

35 DEALING WITH WIND VARIABILITY
SPINNING RESERVE/ON CALL HYDRO ESTABLISHED METHOD IN MOST COUNTRIES ADDITIONAL SPINNING RESERVE MANDATED WITH INCREASED PENETRATION WHO BEARS THE COST? HYDRO AS HEDGE PUMPED STORAGE DINORWIG IN UK KADAMPARAI,SRISAILAM INDIA OPEN CYCLE GAS PLANTS GRID INTERCONNECTS TO HARVEST DIVERSITY FUTURE -STORAGE 35

36 Integration issues of Wind
Planning criterion for RE Variability and Intermittancy Forecasting and Scheduling SCADA / telemetry Network related Problems and Congestion Protection Commercial mechanism implementation

37 Need for Accurate Forecasting
Maintain Load Generation balance Increasing penetration of RE Absence of spinning reserve Perennial deficits in Generation Effect of Higher Intermittency of RE Thrust on Market participation of RE Ensure level playing field to Buyers of RE Favorable policy to RE vis-à-vis Accountability of RE gen Forecasting with minimum accuracy of 30% for wind and 20% for Solar – IEGC mandate Day ahead forecast for 15 min time blocks

38 Uncertainity in a narrow band, Hence it is possible to Forecast Wind generation

39 Align forecast with Scheduling granularity
How the Forecast is done? Inputs : Meteorological data of Weather from satellites, Site topography, SCADA/ current data of weather, power, and historical data of weather and power Earth surface divided into a grid of 35x70km and Earth’s atmosphere into 64 layers The meso scale models further divide the data into 2.5 sq km or 0.5 sq.km grid A digital model of Flow modelling, wake effect, and turbine output Forecast methods are based on statistical techniques involving Numerical Weather Prediction (NWP), Adaptive techniques, Time Series Anlaysis, Climatology. Inputs are fed to different Suite of models which are distinctly based on An intelligent model will combine the results of these individual models and gives a best fit of results. The results are continuously fine tuned by taking real time data inputs from wind farms on live updates of wind speed, live SCADA and site geography. Output :The wind forecast is based on Forecast process is done upto 16 days ahead, In the first 7 days it is run for 3 hour intervals while for the remaining period it run for 8 hour intervals. On day ahead basis, it is run for 4 times for a window of 6 hours with a granularity of 10 minutes, which has to be ultimately aligned with 15 min average values. The errors will be lesser and uncertainty band will be tighter for shorter forecast horizons. Align forecast with Scheduling granularity 39

40 Flow Diagram of a Forecast model
NWP Forecast Suite of Models Power model forecast Model adaptation Wind speed Historic SCADA Live Adaptive statistics Climatology Time Series Intelligent Model Combination Optimised combination of NWP suppliers Incorporation of mesoscale models Regular live feedback from the wind farm “Learning” Algorithms for: Meteorology Power models Site geography

41 Emphasis on Accuracy of Ramp Events
Comparison of Actual power with predicted Values Emphasis on Accuracy of Ramp Events

42 Aggregating of Forecast
Geographic area-wise Control Area-wise Developer-wise Windfarm wise Seller-wise Bilateral vis-à-vis Collective 4.i) of Complementary Commercial Mechanisms of IEGC Day ahead forecast: Wind/ power forecast with an interval of 15 minutes for the next 24 hours for the aggregate Generation capacity of 10 MW and above. Mapping to Transaction-wise is important

43 Variability over a large Area is lesser
Single Turbine A Windfarm A Control Area The forecast when aggregated on a larger Geo-graphical area will give lesser errors 43

44 Forecast to be furnished to
Host Control Area For Operational planning and Real time Monitoring RLDC For Checking the Schedule Vs Actual Forecast model to be adopted for Indian weather conditions Special Emphasis on Ramp Events Advance info on Forecast of Ramp Events to be given to System Operation at regular intervals and time horizons Common Control centre for co-ordinating with RLDC/ SLDC suggested

45 Forecast Data Flow to various functionalities
Real Time Monitoring Reserve Balancing Telemetry Forecasting/ Scheduling Trading

46 Need for Scheduling leads to……
Forecasting Revising to minimise UI Real Time monitoring (SCADA requirements) Need to measure Actuals (Metering) UI accounting (pool participation) RRF

47 Scheduling applicability
Wind farms with collective capacity >= 10MW Solar generating plants with capacity >= 5MW connected at >=33 KV level who have not signed any PPA with states/UTs/DVC or others Nodal developer to be identified for co-ordination for SCDA, Metering, Scheduling, UI Charges, RRF etc. Scheduling of RE w.e.f

48 How to accommodate Forecasted changes in Bilateral and Collective Schedules?
No Revision allowed in Collective schedules Revisions upto a max 8 times in day ( 1 for each 3 hr time slot) allowed in bilateral Revisions after a 6 time block notice Treat Collective as Fixed and revise the Bilateral as per forecast changes +ve changes : Easier to Manage -Ve Changes : L-G balance and Frequency will be effected. How to manage Ramp Events?

49 Intervals for Revisions of Intra-day Bilateral Trade Schedules
6 blocks notice 3 hours 3 hours 3 hours 3 hours 3 hours 3 hours 3 hours 3 hours

50 Why limit Sale under Collective transactions (Px) ?
Collective schedules can not be revised. Real time Deviations due to fixed collective schedules to be factored for operational planning Procedures for RRF mechanism :3.6. The concerned SLDC/RLDC will be responsible for checking that there is no gaming (gaming is an intentional mis-declaration of a parameter related to commercial mechanism in vogue, in order to make an undue commercial gain).

51 Px schedules can not be revised

52 Integration issues of Wind
Planning criterion for RE Variability and Intermittancy Forecasting and Scheduling SCADA / telemetry Network related Problems and Congestion Protection Commercial mechanism implementation

53 Telemetry is a must for scheduling and monitoring
IEGC mandates… Wind farms shall have communication channel which is continuously available to system operator. - Data Acquisition System facility shall be provided for transfer of information to concerned SLDC and RLDC Telemetry is a must for scheduling and monitoring

54 SCADA and telemetry : Due to dispersed and distributed nature of the wind generation across a large geo-graphical area, telemetering the data is a challenge Real time data from wind turbines is metered and shall be transmitted to the local control centre of each wind farm. The net injection of the wind farm is also measured at the pooling station and transmitted to the Area control centre (SubLDC), which in turn is re-transmitted to SLDC As of now Only partial data is transmistted to SRLDC. Sometimes manually replaced data is sent

55

56 Reactive compensation of Wind farms can be utilised by Grid operator
Typical Windfarm Layout VCB 33KV - Internal Lines 33KV - External Lines Cluster-1 Cluster-2 Cluster-3 L1 L2 L3 Billing Meters Transmission Grid Grid Substation WINDFARM WINDFARM SS G1 G2 UTILITY SS 220 KV 132 KV 110 KV 66 KV Local Loads Reactive compensation of Wind farms can be utilised by Grid operator 56

57 Integration issues of Wind
Planning criterion for RE Variability and Intermittancy Forecasting and Scheduling SCADA / telemetry Network related Problems and Congestion Protection Commercial mechanism implementation

58 Each Region has to conduct Studies to know How much wind can be accomodated Congestion anticipated after Kudankulam (2x1000MW) new IPPs in coastal TN and AP come up

59 Integration issues of Wind
Planning criterion for RE Variability and Intermittancy Forecasting and Scheduling SCADA / telemetry Network related Problems and Congestion Protection Commercial mechanism implementation

60 Protection requirements for RE :
Under-Voltage/ Over Voltage protection Under frequency / Over frequency protection Over current and earth fault protection Load unbalance (negative sequence ) protection Differential protection for WTG and grid connecting Transformer. Capacitor bank protection

61 Protection requirements for RE :
Reactive Compensation (0.95 pf lag or lead) Fault Ride Through (FRT) Lightning protection of WTG system shall be according to IEC TR Preferred configuration of the grid connecting transformer is delta connection on the wind farm side and grounded wye connection on the transmission system (grid) side to block the harmonics current and to detect the earth faults on the grid side .

62 Fault Ride Through / Low Voltage Ride Through (FRT/ LVRT)
WTG to stay connected to the grid during voltage dips caused by short-circuit one or all phase of its terminal current upto a specified voltage level. It is achieved through modifications of the turbine generator controls . This capability is essential as large scale trippings of Wind Turbines in large Wind farms result in disturbance in load flows. This should be achieved without damaging the WTG due to unbalance torque, Electronic and mechanical components.

63 Integration issues of Wind
Planning criterion for RE Variability and Intermittancy Forecasting and Scheduling SCADA / telemetry Network related Problems and Congestion Protection Commercial mechanism implementation

64 Commercial Options for RE Gen
Scheduling by ? REC eligible ? Cost Revision in Scheduling Forecast Reqd? 1 PPAs with home state( Preferential Tariff By SLDC No FIT ( as decided by SERC) As per state policy Required 2 Bilateral with an Intra-state buyer Yes Mutually negotiated 3 Bilateral with an Intra-Regional state buyer By RLDC Max once in 3 hrs. 1.5hrs notice 4 Bilateral with an Inter-Regional state buyer By RLDCs Max once in3 hrs. 1.5hrs notice 5 Collective transaction through Px Price discovered thro’ Auction Not allowed

65 Options for DISCOMs to fulfill RPO
What is RPO ? Renewable Purchase Obligation specified by SERC. It will : Incentivise the RE generator Socialise the cost of variations by RE Reduce the Geographical imbalances in RE spread

66 Options for RE generators
Prefrential Tariff [State Regulated Tariff] REC Option Electricity Green Attributes Sale of electricity to Obligated Entities at State regulated tariff REC [Solar & Non-Solar] Sale of Electricity at Market Price in open market Sell to DisComs at Price ≤ Pooled Cost of Power Purchase* Sale of RECs at Power Exchange * - Weighted Average Pooled Price at which distribution licensee has purchased electricity (including cost of self generation, long-term and short term purchase) in the previous year, but excluding the cost of RE power purchase 66

67 REC Framework: Eligibility
Grid Connected RE technology approved by MNRE Self Consumption/ Captive use Third party sale/Open Access PPA with Distribution Licensee No Promotional Wheeling No Promotional Banking No Electricity Duty Exempt Sale at Mutually Agreed Price PPA at Average Power Purchase Cost PPA at Preferential Tariff Eligible Eligible Not Eligible Eligible if All Three conditions mentioned above are met 4/14/2017 67

68 Steps involved in REC mechanism
SERCs to specify Renewable Purchase Obligationat 5% in year 2010, increasing 1% every year for 10 years. SERC to designate SA CERC to designate CA State Agency (SA) gives Accreditation of RE generator Central Agency (CA) for Registration of RE and operate RE registry Px for Price discovery RE generators to apply for REC (within 3 months of generation) SLDC to certify the RE generation CA issues REC based on SLDC Certification (Solar and Non-solar) RE can trade REC in either IEX or PxIL One REC for 1 MWh of electricity injected (365 days from the date of issuance) REC would be issued to RE generators only REC mechanism is expected to overcome geographical constraints Facilitate effective implementation of RPO compliance, reduce risks for local Discom, reduce transaction costs create competition among different RE technologies

69 Salient features …… Recognition
SERC to recognize REC as valid instrument for RPO compliance State Agency SERC to designate State Agency for accreditation for RPO compliance and REC mechanism at State level Central Agency CERC to designate Central Agency for registration, issuance of REC, repository for implementation of REC framework at national level Only accredited project can register for REC at Central Agency Non solar REC (Rs/ MWh) Solar REC Forbearance Price 3,900 17,000 Floor Price 1,500 12,000 69

70 REC sale as on 30-03-11 Non-Solar Solar RECs issued 532 Nil Buy Bid
70377 30001 Sell Bid Cleared Volume Price discovered 3900/2225 ----- No. of participants 15

71 Outline of this presentation
Introduction Basics of Renewable Technologies Scenario of Renewable Energy generation in India Issues involved in Grid Integration of RE: International Experience The Road ahead

72 World wide Wind Installed capacities
Country         Inst. capacity (MW) China 42,287 United States 40,180 Germany 27,214 Spain 20,676 India 13,065 Italy 5,660 France United Kingdom 5,204 Canada 4,009 Denmark 3,752 As in 2010

73 GEMAS – a tool for RE integration computes Max. Admissible Wind Gen.
GEMAS carries out every 20 minutes 3-ph dead faults in the bus bars of 70 different substations.

74 Outline of this presentation
Introduction Basics of Renewable Technologies Scenario of Renewable Energy generation in India Issues involved in Grid Integration of RE: International Experience The Road ahead

75 Storage Technologies to address variability
Pumped hydro storage High Energy Battery storage Storage Capacitors Superconducting Magnetic Energy Storage (SMES) Compressed Air Energy Storage (CAES) Flywheel energy storage Thermal Energy Storage Smart Grid applications Plug-in Hybrid Electric Vehicles (PHEV)

76 KADAMPARAI PUMP MODE ON 18-MAR-03
6MUs pumped 76 76

77

78 Need for develop Real time tools Assess Stability Limits
Conclusions With Larger Grid interconnection The variability can be better handled. With Forecasting, Operational planning can be better executed With Scheduling accountability is induced With REC mechanism and trading across seams, RE will be an attractive business Retrofitting of old machines Need for develop Real time tools Assess Stability Limits

79 Thank You


Download ppt "Integration of Renewable Energy"

Similar presentations


Ads by Google