Oncor Electric Delivery Distributed Storage and Microgrid Demonstration Projects Nathan Kassees BSEE Maintenance Strategy & Planning Nathaniel.Kassees@Oncor.com 5/8/2015 1
Neighborhood Storage Reliability Initiative Goals Demonstrate the use of energy storage technology to improve reliability Outage backup Voltage regulation Gather performance data to identify value of technology on system SAIDI minutes saved Efficiency Customer feedback 2
S&C Community Energy Storage 25 kw, 25 kwh Installed at single phase 120/240 secondary 6 on Oncor System (South Dallas & Lancaster) Supports residential homes during outages and maintains voltage within mandated levels (114 126 V) 3
Configuration Transformer 800 V DC Current Power Converter 120/240 V AC current Internal 240 V AC Breaker Batteries (Underground) 4
Example: Outage CES Tie Breaker 5
Example: Outage CES Tie Breaker 6
Example: Outage CES Tie Breaker 7
Normal Switching Scheme 8
Bypass Switching Scheme 9
CES Testing 25 kw Load Island Test 26.7 ms Transition to Inverter 33.0 ms Transition to Grid 10
Safety Self-Isolation of the CES removes the system as a potential backfeed onto the circuit during outages Category 1 clothing and class 2 gloves are sufficient for protection of the voltages present inside CES Arc flash hazard is no higher than anywhere else along a 240 V secondary line Operations personnel have disconnect procedures to follow to quickly isolate CES 11 Oncor Confidential - For Internal Use Only
Oncor Community Energy Storage Demonstration Project Location Selection 120/240 Single Phase Test Installation South Dallas Target Area High SAIDI Feeders Customer Verbal Approval Available Space Noise 12
Summary Location Date Energized Efficiency Island Operations Total Island Time Test Location (Microgrid) 4/17/14 N/A 4 359 minutes Location 1 7/12/14 95.35% 6 443 minutes Location 2 12/22/14 96.36% 2 35 minutes Location 3 12/22/14 96.85% 0 N/A Location 4 12/22/14 98.53% 1 3 Location 5 12/22/14 97.77% 2 124 minutes Multiple instances of voltage regulation, mostly due to high voltage, have occurred with multiple units. 13
Lessons Learned High Impedance and bolted fault testing, inrush/motor start testing emphasized Sizing specifications Bypass switching scheme improves operational efficiency Tie breaker relay setting needs to be easily adjusted Energy Storage System controller s power supply should be fed directly from battery 14
Oncor Microgrid Demonstration Project Goals Autonomously controlled microgrid Multiple generation sources, both renewable and nonrenewable Demonstrate the ability to seamlessly combine and switch between multiple generation sources Remotely control from user-friendly GUI Develop an Immersion Room capable of displaying the evolution of the power grid 15
SOSF Microgrid Plan Existing Components: TOC 1 2 175 kw Diesel Backup Generators 1 1 50 kva UPS Transformer Shop 1 25 kw/25kwh Battery Meter Services 13 5 1 45 kw Propane Backup Generator Planned Components: Site: 5 Intelliteam on Grid Sources Primary Meter Point Planned Environmental Lab 11 Microgrid Demonstration/Education Center 13 Solar Battery Propane Microturbine 11 Microgrid Control System Meter Services 13 1 210 kw Diesel Backup Generator 16 4/24/2015
SOSF Micro Grid Site Layout Propane Micro-turbine Ground mounted PV Array PV Canopy Battery
Microgrid One-Line
Preferred Sequence of Operations
Tesla Battery 200 kw/ 400 kwh Stationary Storage Six 70 kwh Li-Ion batteries Two 100 kw bidirectional Princeton Inverter/Chargers Specifications DC Capacity: 420 kwh Nominal AC Power: 200 kw Voltage Range: 288-403.5 V DC Nominal Voltage: 345 V DC Efficiency: 85%, Roundtrip Nominal Discharge Current (per sub-pack) : 320 A DC Peak Discharge Current (per sub-pack): 350 A DC Input Voltage(communications and charging) : 3 phase 480 V
Solar Canopy and Ground mounted PV Array Canopy 112 kw DC Composed of the following: 448 Kyocera KD F 250 W modules 6 SMA Sunny Tri Powers 480/277 V centralized inverters 97% Efficiency Large, full cantilever tapered tee support structure Ground Mount 3.5 kw DC Single pole mounted inverter Schletter FS ground mount racking
65 kw Propane Micro-turbine Specifications Output Power: 0-65 kw Output KVA: 65 kva Voltage Operating Range: 360-528 V AC Max Output Current: 100 A Short Circuit Rating: 145 A Power Required at Start: 6.8 kw peak, 0.014 kw/hr, 42 seconds Cool Down Power: 2.0 kw peak, 0.3 kwh for 90 seconds Standby Power: 0.8 kw Grid Inrush Current: 24 A Starting Current from Grid: 16 A Output Power Slew Rate: 1.15 kw/sec (900 rpm/sec)
Generators Total of 4 generators on site supporting the micro-grid at various locations Micro-grid Section 2 Generator 2 210 kw 480 V Generator 4 45 kw 120/208 V Micro-grid Section 1 Generator 3 175 kw 120/208 V Generator 5 175 kw 120/208 V Generator 2 and Generator 5 do not sync correctly and therefore cannot be paralled. As a result, Micro-grid sections 1 & 2 can not be tied in to support Micro-grid section 3
Transformer 16 ABB 500 kva, 12.47 kv/480/277 V with 480 V Delta Tertiary The Delta Tertiary winding has an electrically actuated contactor inside of the cabinet This contactor is used to provide a 480 V and 12.47 kva ground reference when Microgrid Section 1 is islanded