Power Systems Large Scale and Micro-Grid 7/16/2014 NREL - Golden Colorado
Team Leader: Sal Sferrazza Electrical Engineer NREL Team Members Nancy VyasSafety EngineerArmy Research Laboratory Bill BrooksPrincipal EngineerBrooks Engineering Chris Brooks Principal Manager ESC Engineering Inc. Edward ChesneyElectrical CoordinatorLawrence Livermore Nat. Lab Thomas NehringPrincipal EngineerBrookhaven Natl. Lab Bernie RuffenachPresident Electrical Safety Consulting Brian Sautter EngineerSavannah River – DOE Eric StrombergEngineer / Safety OfficerLas Alamos National Lab John Stultz Code Inspector/NFPA 70 EPantex – Consolidated Nuclear
This Working Group focused on the following electrical safety issues, with diverse sources and storage of energy: Interconnection Distribution Assessment of Hazards Arc Flash Risks Shock Risks Signage - Warnings Fault assessment and mitigation Energy storage systems Procurement and Acceptance criteria Maintenance and Operations Procedures and Policies Control of all Electrical Sources PPE LOTO
Micro-grid: A localized grouping of electricity sources and loads that can operate autonomously or can be connected to the utility grid Large Scale: A power system that is under the control of the utility system operator Power System: A power source or group of sources that work together to supply electrical loads Power Source: Equipment that converts non-electrical energy into electrical energy to be used in a power system
Utility System: A power system that is regulated by a public utility commission Service: The conductors and equipment for delivering electric energy from the serving utility to the wiring system of the premises served
Identified applicable codes, standards and procedures for electrical power sources within DOE sites Design guidance related to operation and maintenance Interconnection – IEEE 1547, local utility, ISO, FERC, NERC PV standards – UL 1703, UL 1741, UL 61730, UL 2703, UL Construction / installation guidance NFPA 70 (NEC) Chapters 1-4 and Articles 690, 692, 694, 701, 702, 705 NECA 1 NESC (IEEE C2) NFPA 70E OSHA 1926 Sub Part E, K, M, V NFPA 780 (Lightning protection) Equipment Manufacturer – instructions/guidelines
Identified applicable codes, standards and procedures for electrical power sources within DOE sites continued Operation and maintenance guidance (qualified and authorized) OSHA Subpart I, R (269) NFPA 70E NESC (IEEE C2) Interconnection requirements (IEEE 1547, local utility, ISO, FERC, NERC) Equipment Manufacturer – instructions/guidelines
Codes and Standards currently under development PV standards – ASTM ICOMP WK43549 (O&M); 2017 NEC Article 690 / 691(Proposed)(Large Scale PV Plants); Ground-fault protection upgrades; arc-fault protection upgrades Wind standards and papers, “Arc-Flash Hazard in Wind Power Plants,“ among 11 existing papers that may be rolled into an IEEE guide
Needed Codes, Standards, and revisions NFPA 70E (need better information on dc Arc Flash calculations for PV, batteries, capacitors) Guidance on fault contribution of site sources Specific guidance for special locations (e.g. altitude, lightning, corrosion, dust, temperature extremes, humidity extremes)
Develop Electrical Safety Checklists: Micro Grid System Power Sources Solar Photovoltaic System Energy Storage System Battery Flywheel Inductors/Capacitors Fuel Cell System Wind Power System Hydro Power System
Develop Electrical Safety Checklists: continued Internal Combustion Power System – Renewable and Non-renewable (e.g. Diesel, Natural Gas, Biofuels) Reciprocating Gas Turbine Steam Power System (Geothermal, Biomass,…) Types of Power Converters Static Power Converter Inverter Rectifier Rotating Power Converter Induction Synchronous
Suggested for Future Best Practices Micro Grid Safety Design Checklist Solar Photovoltaic Safety Checklist Battery Safety Checklist Controls Safety Checklist Generators Safety Checklist Renewable Non-renewable General System Operation
Applicable Code References for DOE Sites For contractor work rules at power sources on DOE sites OSHA (a)(3)(iii) - “The contract employer and the host employer shall coordinate their work rules and procedures so that each employee … is protected ….” OSHA Appendix E – Table 2 (Arc Flash Assessment – examples of acceptable methods) NFPA 70E IEEE 1584 Commercially available software programs
Questions ?