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Emerging Electrical Codes for Renewable Energy Sources Mark Konz PE Why are Codes Emerging? • Electricity is not changing-same properties since discovered. • What is changing? – Way we generate it – Ways we control it, i.e. smart grid devices – Tools we use, equipment we use – Ways we use it. More efficient i.e. LEDs What Emerging Codes? • • • • National Electric Safety Code (NESC) National Electric Code (NEC) National Fire Protection Association (NFPA) 70E Occupational Safety & Health Administration (OSHA) Regulations • Local building codes • International Residential Code 2015 • State and National renewable energy mandates What Emerging Codes? continued • • • • • • • International Energy Conservation Code International Mechanical Code International Plumbing Code Nationally Recognized Testing Labs International Building Code International Existing Building Code Uniform Solar Energy and Hydronics Code What Emerging Codes? NESC What Emerging Codes? NESC • NESC- 102 years old (1914) • Purpose-Practical safeguarding of persons, utility facilities, and affected property during the install, maintenance, and operation of electric supply and communication facilities. • Not a design manual What Emerging Codes? NESC • Scope-Supply and communication facilities and work practices employed by a private electric supply, communications, lighting , railway etc. • The generation, transmission and distribution of electricity, lumens, communication signals and communication data through public and private utility systems under the exclusive control of said utility. What Emerging Codes? NESC • Is on a 5 year revision cycle. 2017 out in Aug. 2016 • Composed of 10 subcommittees • The following groups are represented: – Utilities (electric and Communication) – Equipment Manufacturers – Industry associations – Consultants – Enforcement-is a consensus standard Emerging Technologies Working Group • Purpose: Ensure NESC is relevant and adds value for emerging energy generation and storage technologies (Wind, Solar, Battery Storage, others?) • Objectives: – Complete a gap assessment of current NESC requirements and the needs of emerging energy generation and storage system designers, installers, owners and operators. – Author code language proposals to address gaps identified above. – Determine need for code revisions to NESC to address the needs of emerging technologies, and make recommendations to the NESC Main Committee. Representation • Coordinator: Lee Kraemer – NESC Main Committee First Solar • Jim Tomaseski – NESC Exec Sponsor • Greg Ball – DNV – NESC Main Committee Alternate • Joe Cain – Sun Edison • Michael Snyder - Tesla Energy • Jason Spokes – SunPower • Grayling Vander Velde – Next Era Energy (Wind) • Michele Mihelic – AWEA • Sara Kayal – Sun Edison • Robert Preus – NREL/AWEA • Robert Wills - AWEA Key Sections of NESC that Need to Address Emerging Technologies • Scope – Need to recognize generation behind the meter belongs to NEC & need to come to agreement with NFPA that generation on line side of meter belongs to NESC. • Definitions – IPP, PV Array, Wind Turbine, Storage etc… • Section 11 - Protective arrangements in electric supply stations • Section 12 - Installation and maintenance of equipment • Section 14 - Storage batteries • Section 15 - Transformers and regulators • Section 16 – Conductors • Section 17 - Circuit breakers, reclosers, switches, and fuses • Section 18 - Switchgear and metal-enclosed bus • Part 4. Work Rules for the Operation of Electric Supply and Communications Lines and Equipment Next Steps Use the next NEC (2020) and NESC (2022) Code Cycles to: 1) Align on Private Utility issue with NEC 2) Develop NESC requirements for: 1) 2) 3) 4) PV Wind Storage Microgrids 3) Work with State regulators in key markets to ensure NESC is THE Code of choice for energy generation. Will need dedicated resources to be successful What Emerging Codes? NFPA-70 (NEC) What Emerging Codes? NFPA-70 (NEC) • Purpose-The practical safeguarding of persons and property from the hazards arising from the use of electricity. • Scope-Covers the installation of electrical conductors, equipment, etc. for the following: – Public and private premises – Yards, lots, carnivals and industrial substations – Installations used by utilities such as offices, garages, etc. that are not an integral part of a generating plant, substation, or control center. What Emerging Codes? NFPA-70 (NEC) • Enforcement-is intended to be suitable for mandatory application by governmental bodies that exercise legal jurisdiction over electrical installations. – Insurance inspectors – Local code enforcement – Building inspectors What Emerging Codes? NFPA-70 (NEC) • Updated every 3 years • Consists of 19 code making panels • Panels consist of: – Utility representatives – NEMA representatives – Manufacturers – Association of Home Builders reps. – IBEW reps – Many other groups are represented as well NEC Article 690: Solar Photovoltaic Systems – I. General (definitions, installation) – 690.1 Scope—PV Systems (only) – 690.2 Definitions—PV Output Circuit, Inverter Input Circuit—1 ½ pages of PVspecific jargon – 690.3—“Wherever the requirements of other articles of this Code and Article 690 differ, the requirements of Article 690 shall apply” – 690.4—Installation “Equipment: …shall be identified and listed for the application” – 690.5—Ground-Fault Protection—to reduce fire hazards – 690.6—AC Module—dc wiring is considered internal NEC Article 690: Solar Photovoltaic Systems • Solar Photovoltaic Systems – II. Circuit Requirements (sizing, protection) • 690.7 Maximum Voltage—Table 690.7 and manufacturers data. Max. 600Vdc for residential. • 690.8 Circuit Sizing and Current690.8(A) Max current = rated Isc x 1.25 = Imax • 690.8(B) Min ampacity and overcurrent = Imax x 1.25 • 690.9 Overcurrent Protection690.9(A) Generally required on all source circuits— exception: a.)no backfeed; and, b.) total Imax less than conductor ampacity. • 690.10 Stand-Alone Systems Inverter output need only meet demand. • No multi-wire circuits on 120V inverters. NEC Article 690: Solar Photovoltaic Systems • III. Disconnect Means (switches, breakers) • 690.13—Need to disconnect all conductors connected to building. No disconnect in grounded conductor • 690.14—Location—details and options (more to come) • 690.17—Switch or Circuit Breaker—Warning sign when line and load energized in open position. NEC Article 690: Solar Photovoltaic Systems • IV. Wiring methods • 690.31(A) FPN—PV modules get HOT • 690.31—single conductors outside conduit allowed in array. • Table 690.31—temp. correction must be applied to conductors. • 690.33—requirements for connectors. • 690.35—Ungrounded PV Power Systems NEC Article 690: Solar Photovoltaic Systems – V. Grounding (system, equipment) • 690.41 System Grounding Over 50Vdc must be • • • • grounded or comply with 690.35 690.42 Point of System Grounding Connection—one point, at GFP device if provided. 690.43 Equipment Grounding—metal likely to become energized must be grounded—listed equipment can be used to bond modules to support structure.. 690.45 Size of EGC—Table 250.122 with GFP 690.47 Size of GEC—ac use Table 250.66; dc use Table 250.166 NEC Article 691 Will be introduced in 2017 version • 691 – Requirements for Large Scale PV • 691.1 Scope. – This article covers the installation of large-scale PV electric supply stations operated for the sole purpose of providing electric supply to a system operated by a regulated utility for the transfer of electrical energy with a generating capacity of no less than 5,000 kW. Electric supply stations are locations containing the generating stations and substations, including their associated generator, storage battery, transformer, and switchgear areas. Facilities covered by this article have specific design and safety features unique to large-scale PV facilities as indicated in 691 .4. – Informational Note: 90.2(B)(5) includes information about utilityowned properties not covered under this Code. For additional information on electric supply stations, see ANSI/IEEE C2-2012, National Electrical Safety Code. What Emerging Codes? NFPA-70E What Emerging Codes? NFPA-70E • Electrical Safety in the Workplace • Purpose- to provide a practical safe working area for employees relative to the hazards arising from the use of electricity. • Scope-addresses electrical safety-related maintenance requirements and other admin controls for employee workplaces relative to the electrical hazards while maintaining, operating, installing and removing electrical equipment. What Emerging Codes? NFPA-70E • Does not apply to utility workers working on utility installations under the direct control of the utility. • Does apply to utility workers working on other installations NOT under the direct control of the utility. • Includes rules requiring certain levels of protective equipment for voltage classes. What Emerging Codes? OSHA Regulations • US Dept. of Labor established the OSH act in 1970 • employers are responsible for providing a safe and healthful workplace. OSHA's mission is to assure safe and healthful workplaces by setting and enforcing standards, and by providing training, outreach, education and assistance. Employers must comply with all applicable OSHA standards. Employers must also comply with the General Duty Clause of the OSH Act, which requires employers to keep their workplace free of serious recognized hazards. What Emerging Codes? OSHA Regulations: • • • • • General Industry Construction Maritime Agriculture Record keeping What Emerging Codes? OSHA Regulations, continued. • Revised on no set schedule • Usually as need arises-results of accidents • Vigorously enforced – By inspections – After accident investigations – Fines and prison time can result What Emerging Codes? International Building Code • 2015 International Building Code covers all buildings except detached one- and two-family dwellings and townhouses up to three stories. • Updated every 3 years What Emerging Codes? International Building Code • 2015 IBC handbooks also available – Excellent resources to get more detailed info about the intent of code. What Emerging Codes? International Existing Building Code What Emerging Codes? International Existing Building Code • 2015 International Existing Building Code contains requirements intended to encourage the use and reuse of existing buildings. The scope covers repair, alteration, addition and change of occupancy for existing buildings and historic buildings, while achieving appropriate levels of safety without requiring full compliance with the new construction requirements contained in other International Codes What Emerging Codes? International Residential Code What Emerging Codes? International Residential Code • Updated every 3 years • Contains provisions for safeguarding residents • Provisions for photovoltaic system structural and mechanical requirements • Wind loading, snow loading, weather tightness, roof penetrations, provisions for maintenance What Emerging Codes? International Energy Conservation Code What Emerging Codes? International Energy Conservation Code • Updated every 3 years • Provides information on things like: – Solar Access (ability to see the sun, shading) – Sustainability-conservation, renewability and other positive environmental impacts. – Climate criteria What Emerging Codes? International Mechanical Code What Emerging Codes? International Mechanical Code • Updated every 3 years • Regulates those mechanical systems permanently installed and utilized to provide control of environmental conditions and related processes within buildings. • Requires guards, means of access, material compatibility, etc. What Emerging Codes? International Plumbing Code What Emerging Codes? International Plumbing Code • • • • • • Updated every 3 years For active solar water heaters Provisions for pressure relief Tank expansion and contraction Protection from Freezing Backflow prevention What Emerging Codes? Nationally Recognized Testing Labs • • • • • • Underwriter’s laboratories (UL) Canadian Standards Association (CSA) Curtis-Straus LLC (CSL) Intertek MET Laboratories International Association of Plumbing and Mechanical Officials EGS (LAPMO) • Others What Emerging Codes? Underwriter’s labs • Safety and Consulting company in 46 countries • Provides safety related certification, validation, testing, inspection, auditing, advising and training services • Nationally recognized testing lab • Lots of electric equipment may have the “UL listed” sticker on it. Underwriters Lab Standards • UL Standard 1703 – Standard for flat panel photovoltaic modules and panels. • UL Standard 1741 – Standard for Inverters, Converters, Controllers and Interconnection System Equipment for Use With Distributed Energy Resources • UL Standard 2703 – Rack mounting systems and clamping devices for flat-plate PV modules and panels Uniform Solar and Hydronics Code • Applies to the erection, installation, alteration, addition, repair, relocation, replacement, additions to, use or maintenance of solar systems. • Designed to be a one stop shop for codes • American National Standard Solar ABCs • Solar America Board for Codes and Standards • is a collaborative effort funded by the U.S. Department of Energy that dedicates experts to transforming solar markets by improving building codes, utility interconnection procedures, and product standards, reliability, and safety, and is part of its overall strategy to reduce barriers to the adoption of solar technologies and to stimulate market growth Solar ABCs • Summary of Topics Rated Highest Priority – Firefighters and solar industry have different views for module level disconnect – Firefighters are unsure how to fight fires around PV installations – Insurance companies have PV loss concerns – Continued involvement in NEC revision process – Arc fault standard needs to be adopted – Better address storage technologies in NEC Solar ABCs • Need a qualification standard for distributed array electronics • Need stakeholder education on grid connection standard changes and requirements • Wind upload requirements for flush mounted solar arrays • No safety standard exists for disconnect devices • On and on… • Solarabcs.org Why so Many Codes? • • • • • • • Electricity is Inherently Dangerous Tiny amounts of current can kill 1 mA-Threshold of Feeling 5mA-accepted as harmless 7-20mA-muscular contraction(can’t let go) 100-300mA-Ventricular fibrillation, can be fatal 6A-Sustained ventricular contraction. Temporary respiratory paralysis and burns. Why? Relationship between voltage and current • Ohm’s law – Voltage =Resistance X Current – Or Current=Voltage / Resistance • Average resistance human body – Varies-wet, dry etc. – Dry skin-100,000ohm-600,000ohm – Wet skin-1,000ohm Electric Generation in US 2015 (provided by US Energy Information Administration) • • • • • Coal-33% Natural gas-33% Nuclear-20% Hydro-electric-6% Renewables-7% – – – – Wind-4.7% Biomass-1.6% Solar-.6% Geothermal-.4% • Petroleum-1% Renewables are Becoming Mainstream 2014 Capacity Added (MW) GTM Research states that 7.4 GWdc of PV was installed in 2015 Other 456 Rooftop Solar (est.), 2103 Utility-Scale Solar, 3139 Wind, 4080 Natural Gas, 7485 Nuclear, 71 Oil, 47 Coal, 106 Electric Generation What codes apply? • NESC-Part 1 – Safety Rules for the Installation and Maintenance of Electric Supply Station and Equipment Electric Generation NESC Part 1 • Utility owned and operated generation in US is governed by National Electric Safety Code. Part 1 deals explicitly with Electric Supply Stations which includes generation and substations. • There are 37 pages in NESC devoted to these stations in part 1. • Doesn’t matter what kind of station or generation Electric Generation NESC Part 1 • NESC Part 1 rules provide for the safeguarding of persons during the installation, operation, or maintenance of these facilities. • Covers general requirements such as – – – – – layout, safety clearance zone, illumination Installation and maintenance Guarding live parts, guarding moving parts Proper working space Classified locations (contain flammable or hazardous substances) Electric Generation NESC Part 1 • • • • • • Also cover rotating equipment Storage batteries Transformers and regulators Conductors, protective equipment Switchgear and surge arresters Station grounding Electric Generation NESC Part 4 • Work Rules for the Operation of Electric Supply and Communications Lines and Equipment. Section 40-Purpose and Scope • Covers work done anywhere on utility owned and operated electric system including supply stations. • Intent is to safeguard the employees and the public NESC Part 4 • Section 41- Supply and Communication systems-Rules for employers – Employers must notify and train employees on the hazards and safety rules. – Assessments must be done to determine potential exposure to electric arcs. Or use Table 410-1,2 or 3 – Require employees to wear clothing or clothing systems with an arc rating not less than the anticipated level of arc energy – Tables go from 50V-800KV NESC Part 4 • Section 42-General rules for Employees – Employees responsible to be knowledgeable with the safety rules and emergency methods – Employee qualifications – Safeguarding oneself and others – Tools and protective equipment – Clothing suitable for task and arc rated if required – Fall protection is required over 10’ NESC Part 4 • Section 42-General rules for Employees(cont) – 1st line supervisor duties, JSB, proper tools etc. – Area Protection-must protect the public from hazards – Overhead line operating procedures • Setting poles near energized lines • Inspect structures before climbing • Installing or removing wire or cables NESC Part 4 • Section 42-General rules for Employees (cont.) – Underground line operating procedure • • • • Guarding openings Testing for gasses Use of flames in underground facilities Excavations-use of shoring NESC Part 4 • Section 43-Rules for Communications Employees – Communication worker minimum approach tables – Joint use structures- don’t get out of the communications space on pole NESC Part 4 • Section 44-Additional rules for supply employees – Must abide by the minimum approach distances to energized parts-Table 441-1 – AC table and DC table – Switching control procedures – Working on energized lines and equipment – De-energizing equipment or lines to protect employees-employees request – Protective grounds-procedures for installing and removing protective grounds Renewables How they fit in • Utility scale solar and wind • Considered just another type of generation – governed by NESC part 1 and part 4 – Governed by OSHA regulations as well Large Scale Solar Concentrated Solar Power Concentrated Solar Power Wind Generation Wind Generation Wind Generation Renewables Small Scale Solar • Typically 250KW or less • Can be tied to electrical distribution system or not. • If excess capacity is expected then best to attach. Get credit for selling excess electricity back to power company. • Requires special meter and disconnecting equipment. Must be able to disconnect from system in event of widespread outage. Residential rooftop Commercial rooftop Solar Cell Basics • One silicon solar cell produces 0.5 volt • 36 cells connected together have enough voltage to charge 12 volt batteries and run pumps and motors • 72-cell modules are the new standard for gridconnected systems having a nominal voltage of 24-Volts and operating at about 30 Volts. • Module is the basic building block of systems • Can connect modules together to get any power configuration Solar cell to solar array Typical household design Renewables Small Scale Solar • Not governed by NESC • What codes then? – NEC-if in US – IBC, IRC, IEBC – IECC – IMC – USEC – US&HC Small Scale Solar • Can be hazardous to line workers if attached and generating. • Must sign agreement with utility and meet their requirements. • Most utilities have limits to this. – With over 15% they start to lose voltage control of system – Hawaii is example • Using +/- 5% Voltage bandwidth at the meter (or less), and up to 5% voltage drop on line transformer, secondary and service, it is a real challenge to accommodate large amounts of PV. Renewables-Which code? NESC NEC Small Scale Solar On Utility Owned Structures Small Scale Solar On Utility Owned Structures • Located on utility pole in communication space. Owned by utility. – Generates DC voltage – Uses micro-inverter to change to 120V AC – Attaches directly to secondary bushings of transformer. – Injects small amounts of power into the distribution system but lots of installations. Small Scale Solar On Utility Owned Structures • Subject to NESC Part 2 – Safety Rules for the Installation and Maintenance of Overhead Electric Supply and Communication Lines. – Must maintain clearance from other parts and conductors – Must also maintain climbing space on pole – Also places addition load (wind) on pole which must be accounted for. – Rules may be changing to keep up Small Scale Solar • Subject to NESC part 4 – These are the work rules for employers and for employees – MAD distances – Must be qualified and trained – Must wear proper personal protective equipment and clothing or clothing systems – Many more Summary • As you can see there are many codes applicable to the installation, use and maintenance of energy systems. • Location and type dictates which codes • On utility system-generally NESC & OSHA • On other facilities-generally the NEC, NFPA 70E, IBC, IRC, IEBC, IPC, US&HC, IECC • UL listed or other approved equipment are generally required by NEC and hence by inspectors. Summary • We can expect these codes to struggle to keep up with the changing landscape of renewable generation. • You can be sure more changes are coming • Consolidation of the codes would be nice • Local authorities having jurisdiction can require any of the listed codes as they see fit for construction. • Most of these codes are “guidelines” and not the law. They must be adopted the authorities having jurisdiction. Conclusion • It is important to get involved in the rule / code making process to help shape the future • Otherwise all you can do is react to the changes • Some of these changes may not improve safety at all, they may increase costs though due to special interest involvement • Constant challenge to stay current Questions ?