Download Emerging Electrical Codes for Renewable Energy Sources

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?
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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
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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:
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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
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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:
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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
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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
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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?
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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)
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Coal-33%
Natural gas-33%
Nuclear-20%
Hydro-electric-6%
Renewables-7%
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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
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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
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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
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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 ?