Distributed Generation and Impacts to Distribution Systems. FMEA Energy Connections Conference 2017

Transcription

1 Distributed Generation and Impacts to Distribution Systems FMEA Energy Connections Conference

2 Biographies Matt Lundeen has a BSEE degree from the University of Florida and is currently pursuing a MSEE degree specializing in Power and Energy from the New Jersey Institute of Technology. Matt has over 12 years of utility experience with background work including distribution engineering, key account management, and managing a team of engineers performing various electric system power quality and reliability analyses on the JEA system. Matt s current role is to effectively lead a team implementing projects that improve the reliability and power quality of the electric distribution system at JEA. Trishia Swayne is a registered professional engineer with 13 years of experience in electric utility system planning and consulting. She obtained a Bachelor of Science in Engineering Physics and a Master s Degree in Business Administration at Murray State University in Kentucky. She leads a team at Leidos that performs DER interconnection impact studies and distribution planning services such as capital improvement plans, voltage optimization, and system protection and coordination studies for utilities across the United States and the Caribbean islands. 2 2

3 Outline JEA Electric System Overview JEA History with Solar Solar Policy New Solar Projects Solar Challenges with Operations Net Metering Net Metering Policy Challenges Policy Revisions for DG Future Preparations Electric System Potential Impacts of Distributed Generation Study Methodologies in Case Study Study Outcomes in Case Study Conclusions 3

4 JEA Electric System Overview Part 1 JEA is a vertically-integrated electric utility Established in 1883, JEA is the nation s 8 th largest community-owned municipal utility Service Territory Approximately 900 square miles All of Duval County; a portion of St. Johns County and Clay County ~474,000 retail electric customers served Combination of residential, business and industrial Wholesale service to the City of Fernandina System Peaks (Instantaneous) Winter 2009/2010: 3,250 MW Summer 2007: 2,937 MW 2017: 2,505 MW(w); 2,727 MW(s) 4 4

5 JEA Electric System Overview Part 2 Net Assets In-Service: $3.7 billion Power Production Assets 6 Plant sites *, 18 Units * Net Capacity (2017): 3,769 MW (4,110 MW winter) Fuel sources: Oil, Natural Gas, Coal and Petroleum Coke Small amount of renewables (solar and landfill gas) Transmission System Voltage levels (KV): 500, 230, 138, and miles of transmission 74 substations; 200 transformers (high side >= 69kV) Distribution System Voltage levels (kv): 26.4, 13.2 and feeders ( kv; kv; 27 4 kv) 6,760 circuit miles (45% overhead; 55% underground) 102,600 transformers; 200,900 poles * = Includes St Johns River Power Park and Plant Sherer (Jointly Owned) 5 5

6 JEA History with Solar Duval County public schools Jacksonville Zoo Jacksonville Chamber of Commerce Jacksonville International Airport Jacksonville University FSCJ COJ Fire Rescue Station JEA downtown parking 2010 JEA s Jacksonville Solar Project 12MW(AC) solar generation facility PPA (Purchased Power Agreement) for 31 years Fixed array PV panels situated on 100 acres adjacent to JEA s Brandy Branch Generation Station FSCJ Florida State College of Jacksonville COJ City of Jacksonville PV Photovoltaic 6

7 JEA Existing Photovoltaic Resources End of CY2016 Solar Portfolio Program Size (MW) Annual Energy (MWh) JEA Solar PV JEA Solar PPA 12 21,000 Net Metering 6.0 8,300 Total ,428 Solar Thermal 5.5 2,300 Total ,

8 Policy Highlights Solar Policy Key Points Add up to 38 MW of solar photovoltaic (PV) Purchase agreements (PPAs) Include utility-scale and smaller solar-garden scale Customer offerings are being developed Sites offer geographic diversity within the service territory PPA offer to take advantage of 30% federal tax credit End of CY2017 Interim Target Solar Portfolio Program Size (MW) Annual Energy (MWh) JEA Solar PV JEA Solar PPA 12 21,000 New Solar PPAs 32 75,686 Net Metering 10 13,140 Total Solar PV ,026 Solar Thermal 5.5 2,300 Total Solar ,326 JEA Solar Portfolio Will be 4.7 times 2014 levels by the end of 2017 Approximately 1% of JEAs total energy 8 8

9 New Solar Energy JEA Solar Contracts No. Project Company MW Status 1 Jacksonville Solar Jax Solar 12 Online 2 NW JAX Solar Partners Farm* grosolar 7 Online 3 Old Plank Rd Solar Farm VeloSolar/COX 3 Online 4 Starratt Solar Inmansolar 5 Under Constr. 5 Blair Site Solar Hecate 4 Site Clearing 6 Simmons Rd Solar Inmansolar 2 Permitting 7 Sunport Solar Farm NationalSolar 5 Permitting 8 Old Kings Solar MirasolFafco 1 Permitting Total Solar Capacity 39 MW *Formerly referred to as Montgomery Solar 9

10 Solar PV Challenges for Operations JSI Performance by Weather Type 3000 Summer Peak Day System Load MW 2000 MW Clear Few Scattered Broken Overcast MW Hour Winter Peak Day System Load Hour Hour Sky Condition MWH/Day % Output Days % of Year Clear % 53 15% Few (10% sky covered) % 41 11% Scattered (10% - 50% sky covered) % % Broken (60% - 90% sky covered) % % Overcast (100% sky covered) % 42 12% MWH % Output Total Output (If 100% Clear) 34, % Total Output (2013) 21,183 61% Losses Due to Weather 13,621 39% PV Photovoltaic JSI JUWI Solar Inc 10

11 Net Metering Program started in 2009 Put in place to test and incentivize the emerging customer-owned solar market Incentives result from utilities paying customers for all excess generation at the retail rate Solar system buyers also receive a 30% Federal tax credit for the value of their purchase. 428 of the 1,276 net metering customers were installed in FY17 approximately 34% 11

12 Net Metering Policy Challenges The existing Net Metering policy creates an unsustainable cost of service recovery condition within the residential rate class. Energy delivered to JEA is purchased at full retail (~$0.11) versus avoided cost which is essentially the fuel rate currently around $ per kwh. Impacts recovery of the fixed assets associated with owning and maintaining the infrastructure of the generation fleet, transmission, and distribution systems through the variable per kwh consumed energy charge. 12

13 Policy Revisions for DG Revised Policy approved in October pay fuel rate for energy sent to JEA. Introduced Battery Incentive Program to encourage customers to store excess energy, preserving customer economics. Considering possible rate structures to more accurately reflect cost structure such as solar rate derived from JEA cost of solar, and a residential demand rate. DG Distributed Generation 13

14 Keeping Up With the Pace IEEE 1547 Updates Working Group targeting Q2/Q3 of 2018 for publishing revised 1547 standard Smart Inverter Working Group/Rule 21 Phase 1 has been adopted and autonomous functions established in phase 1 are mandatory after September 8 th, 2017 Phase 2 and Phase 3 are currently being worked on by the SIWG JEA Interconnection Requirements Updates Revising interconnection standards based on project experience where TrOV exists using existing 1547 standard and to incorporate Smart Inverter capabilities TrOV Transient Overvoltage 14

15 Distributed Generation Potential Impacts Thermal Loading Short Circuit, Protection, and Grounding PQ Implications such as Flicker Unintentional Islanding/Safety Dynamic Stability System Upgrades TrOV Substation Transformers Load Tap Changer Operations Load Flow and System Planning Afternoon Storm PQ Power Quality 15

16 Case Study Methodologies Case Study 7 MW PV site 26.4 kv distribution circuit Existing rooftop penetration of PV = 168 kw Peak daytime load = 10.4 MW Light daytime load = 2.5 MW PV photovoltaic 16

17 Case Study Methodologies Analyses Comments Steady State Analysis Capacity, voltage, power factor, reverse power flow, tap movement Voltage Flicker Short Circuit and Protection Risk of Islanding Voltage fluctuations due to intermittent source Device ratings, effective grounding, reclosing, coordination Sandia Report Screening method Transient Analysis Load rejection, ground fault, in-rush, overvoltage 17

18 Reverse Power Flow No concern Case Study Outcomes 18

19 Case Study Outcomes Steady State Analysis Existing low voltage not exacerbated by Project One LTC tap movement at peak with Project Power factor at substation acceptable (> 95%) Capacity violation on tap to Project site; 5 miles upgraded to 636 aluminum LTC Load Tap Changer 19

20 Case Study Outcomes Voltage Flicker Pst and Plt evaluation - acceptable Single worst case event = 3.81%; is a concern Pst Short Term Flicker; Plt Long Term Flicker 20

21 Case Study Outcomes Short Circuit and Protection Fault contribution 18% of maximum fault current at POI Two upstream devices between the feeder relay and POI; 65T fuse and recloser (see next slide) Need to move overloaded fuse downstream of POI Fast curves of recloser do not leave margin for a POI site recloser; recommend upgrade to electronic and slow down fast curves Reclosing at feeder relay to start at 2 seconds or beyond POI Point of Interconnection 21

22 Short Circuit and Protection Case Study Outcomes 22

23 Case Study Outcomes Risk of Islanding Sandia Screening Method Results in negligible risk Red flag is PV penetration concerns Circuit 393 PV/Load = 294% Circuit 393 Midstream recloser PV/Load = 740% Red flag is PV penetration concerns Next steps Transient analysis in PSCAD PV photovoltaic 23

24 Case Study Outcomes Transient Analysis Load rejection (feeder and mid-stream recloser) Ground fault analysis Energization (in-rush) analysis Note: Follow Transient Overvoltage (TOV) criteria from IEEE 1547 Transient Overvoltage Curve (draft) 24

25 Case Study Outcomes Load Rejection Violation with transient overvoltage with midstream recloser event Solution requires inverter to have instantaneous response to voltage violations VintPOI Source Current : Graphs sec

26 Conclusion Key Takeaways Importance of customer education as it pertains to various technologies such as PV...to better understand foundation of policies developed by utilities and/or PUC s/psc s/boards Set priorities on keeping up with technologies/markets and how that may impact standards/policies/internal procedures/operations etc Good data for studies is key Even minor mitigations determined in studies could lead to major operations and reliability issues 26

27 Questions Matt Lundeen (904) Trishia Swayne, P.E. (615)