Clean Energy Question of the Week
IREC and our EMPOWERED partners are committed to providing you with up to date, reliable, and vetted information that meets your needs. Join us each week for answers to your clean energy questions provided by leading industry organizations. The answer to each question contains links to additional resources you can explore to learn more!
Check out this week’s question and answer:
In today’s dynamic energy environment, new methods have emerged for managing power sources and their integration into building wiring systems, as well as exporting surplus electricity generated onsite back into the utility grid. For example, as more energy storage systems are being installed, technology has advanced to keep up with the evolving energy landscape. The speed of adoption has created some misunderstandings as to what a“transfer” switch is.
A stand-by generator is typically connected through a transfer switch. These units are neither synchronized with, nor are they ever connected to, the utility grid. The load is supplied by either the generator or the utility, but never both sources.
By contrast, a utility-interactive energy storage system is synchronized with the utility and always connected to both the load and the utility unless the utility is de-energized. If the utility grid goes down a microgrid interconnect device (MID) isolates the utility source. This MID acts differently than a transfer switch.
Incorrect installations can result when the distinction between parallel power production sources like an energy storage system, and a generator-based optional standby system connected through a transfer switch, is not fully understood.
Read More:
This short course, Energy Storage Systems and Generators: Some Critical Distinctions, will clarify when a system is able to produce electricity in parallel with the grid and highlight the applicable code requirements for utility-interactive interconnected energy storage systems.
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Solar
To inspect any system with batteries, at a minimum you should have voltage-rated gloves and safety glasses. Battery chemistry can range from flooded lead acid to lithium ion. The common factor is that a battery bank can store a lot of energy, and can discharge that current instantaneously. Have the right PPE for the job. And be sure to have a copy of the plan with you for all inspections. As more and more solar-plus-storage systems make their way into your jurisdiction, you will want to ensure a proper plan review before showing up on site for an inspection. This will help you ensure the system is designed to code, understand all the components configured in the system, and help you prepare what to bring on site for a safe and successful inspection.
Learn More
In this resource, take a tour of an inspection in Liberty, North Carolina of a ground mounted AC-coupled PV system with energy storage. The tour is led by IREC’s Joe Sarubbi and Rebekah Hren, Solar PV and Energy Storage Systems Subject Matter Expert and NEC Code Making Panel 4 Member.
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Standard permitting and inspection processes for solar photovoltaic (PV) systems and energy storage systems (ESS) can vary greatly across local jurisdictions, increasing costs and extending project timelines for building officials, contractors, and system owners. For many residential projects, including rooftop PV systems up to 15 kilowatts (kW) and in some cases for ESS up to 80 kilowatt-hours (kWh), a simplified process can ensure that projects are safe, effective, and in compliance with universally adopted construction codes.
To streamline permitting, building officials can download a six-step checklist covering the information required for permitting review, electrical requirements, structural requirements, and more. For field inspections, building officials can download checklists that address notable installation requirements for PV systems and ESS. The inspection checklists can be customized with state and local requirements. Bill Brooks, an industry expert and principal engineer at Brooks Engineering, drafted each set of checklists with support from the Sustainable Energy Action Committee, SolSmart, and IREC.
Learn More:
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Solar energy systems can sometimes face more complicated and costly permitting processes in areas where permit reviewers are less familiar with the technology. A simplified process can help streamline the permitting of most residential rooftop photovoltaic (PV) systems, including those with energy storage. This simplified process can help reduce informational barriers and ensure that all items in the inspection process have been adequately addressed before inspectors arrive on site.
Learn More
If you are a plan reviewer, inspector, or installer, these permitting and inspection guides from the New Buildings Institute provide an overview of code requirements for the installation of energy storage systems (stand-alone and paired with simple photovoltaic systems) in single-family, multifamily, and office buildings.
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Energy storage systems (ESS) are becoming more common across the country. When inspecting a PV + ESS, there can be a lot of system components to review, from the modules, to inverters and disconnects, to the ESS itself. To ensure a safe and correct inspection, it is valuable to understand the system components you will encounter and how to refer to approved plans and installation manuals.
Learn More
In this instructional video, you will learn from Chief Electrical Inspector Pete Jackson about the ins and outs of a solar PV system with a string inverter and a Tesla PowerWall in Bakersfield, California. This video course will help you educate yourself about the components of the system and related codes and standards, as well as permitting and inspection guides.
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Energy Storage
In today’s dynamic energy environment, new methods have emerged for managing power sources and their integration into building wiring systems, as well as exporting surplus electricity generated onsite back into the utility grid. For example, as more energy storage systems are being installed, technology has advanced to keep up with the evolving energy landscape. The speed of adoption has created some misunderstandings as to what a“transfer” switch is.
A stand-by generator is typically connected through a transfer switch. These units are neither synchronized with, nor are they ever connected to, the utility grid. The load is supplied by either the generator or the utility, but never both sources.
By contrast, a utility-interactive energy storage system is synchronized with the utility and always connected to both the load and the utility unless the utility is de-energized. If the utility grid goes down a microgrid interconnect device (MID) isolates the utility source. This MID acts differently than a transfer switch.
Incorrect installations can result when the distinction between parallel power production sources like an energy storage system, and a generator-based optional standby system connected through a transfer switch, is not fully understood.
Read More:
This short course, Energy Storage Systems and Generators: Some Critical Distinctions, will clarify when a system is able to produce electricity in parallel with the grid and highlight the applicable code requirements for utility-interactive interconnected energy storage systems.
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As battery energy storage systems (BESS) become more prevalent, pre-incident planning holds a pivotal role in ensuring effective and safe emergency response. By proactively familiarizing fire service professionals with the intricacies of BESS installations, potential risks, and emergency protocols, pre-incident planning equips responders with critical knowledge. Understanding battery technology, storage locations, shut-off procedures, and containment measures enables firefighters to make informed decisions during emergencies, minimizing the risk of catastrophic incidents and enhancing their ability to protect lives and property. Incorporating pre-incident planning for battery-related incidents is not just about adapting to a changing energy landscape; it’s about empowering fire service professionals to confidently navigate the evolving challenges of firefighting in an electrifying world.
Learn More:
The American Clean Power Association recently released guidance for first responders, the First Responders Guide to Lithium-Ion Battery Energy Storage System Incidents. This guide provides recommendations for pre-incident planning and incident response specific to ESS with lithium-ion batteries, and also covers hazards including fire, explosion, arc flash, shock, and toxic chemicals. Use this guide to invest in your training and be prepared as the energy industry transforms!
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To inspect any system with batteries, at a minimum you should have voltage-rated gloves and safety glasses. Battery chemistry can range from flooded lead acid to lithium ion. The common factor is that a battery bank can store a lot of energy, and can discharge that current instantaneously. Have the right PPE for the job. And be sure to have a copy of the plan with you for all inspections. As more and more solar-plus-storage systems make their way into your jurisdiction, you will want to ensure a proper plan review before showing up on site for an inspection. This will help you ensure the system is designed to code, understand all the components configured in the system, and help you prepare what to bring on site for a safe and successful inspection.
Learn More
In this resource, take a tour of an inspection in Liberty, North Carolina of a ground mounted AC-coupled PV system with energy storage. The tour is led by IREC’s Joe Sarubbi and Rebekah Hren, Solar PV and Energy Storage Systems Subject Matter Expert and NEC Code Making Panel 4 Member.
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The International Residential Code (IRC) serves as a complete, comprehensive code regulating the construction of single-family houses, two-family houses (duplexes), and buildings consisting of three or more townhouse units. All buildings within the scope of the IRC are limited to three stories above grade plane. Section R328 of the IRC covers ESS, specifically the requirements focused on product safety standard listing, code-required marking, and clarifying allowable locations.
Learn More
The following informational bulletin developed by the Sustainable Energy Action Committee (SEAC) provides a quick reference on these important requirements.
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Standard permitting and inspection processes for solar photovoltaic (PV) systems and energy storage systems (ESS) can vary greatly across local jurisdictions, increasing costs and extending project timelines for building officials, contractors, and system owners. For many residential projects, including rooftop PV systems up to 15 kilowatts (kW) and in some cases for ESS up to 80 kilowatt-hours (kWh), a simplified process can ensure that projects are safe, effective, and in compliance with universally adopted construction codes.
To streamline permitting, building officials can download a six-step checklist covering the information required for permitting review, electrical requirements, structural requirements, and more. For field inspections, building officials can download checklists that address notable installation requirements for PV systems and ESS. The inspection checklists can be customized with state and local requirements. Bill Brooks, an industry expert and principal engineer at Brooks Engineering, drafted each set of checklists with support from the Sustainable Energy Action Committee, SolSmart, and IREC.
Learn More:
0
0
Solar energy systems can sometimes face more complicated and costly permitting processes in areas where permit reviewers are less familiar with the technology. A simplified process can help streamline the permitting of most residential rooftop photovoltaic (PV) systems, including those with energy storage. This simplified process can help reduce informational barriers and ensure that all items in the inspection process have been adequately addressed before inspectors arrive on site.
Learn More
If you are a plan reviewer, inspector, or installer, these permitting and inspection guides from the New Buildings Institute provide an overview of code requirements for the installation of energy storage systems (stand-alone and paired with simple photovoltaic systems) in single-family, multifamily, and office buildings.
0
0
Energy storage systems (ESS) are becoming more common across the country. When inspecting a PV + ESS, there can be a lot of system components to review, from the modules, to inverters and disconnects, to the ESS itself. To ensure a safe and correct inspection, it is valuable to understand the system components you will encounter and how to refer to approved plans and installation manuals.
Learn More
In this instructional video, you will learn from Chief Electrical Inspector Pete Jackson about the ins and outs of a solar PV system with a string inverter and a Tesla PowerWall in Bakersfield, California. This video course will help you educate yourself about the components of the system and related codes and standards, as well as permitting and inspection guides.
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With the prevalence of energy storage system (ESS) installations, codes and standards have been updated to address the technology. Product standards like UL 9540 and testing like 9540A allow for safer installation of energy storage systems.
- References to ESS appear in the I-Codes:
- and NFPA Standards:
- NFPA 1 Fire Code
- NFPA 70, National Electrical Code, Article 706
- NFPA 855, Standard for the Installation of Energy Storage Systems
- NFPA 110, Standard for Emergency and Standby Power Systems
- NFPA 111, Stored Electrical Energy Emergency and Standby Power Systems
The codes and standards require electrochemical ESSs to be listed in accordance with UL 9540, the Standard for Safety of Energy Storage Systems and Equipment, which was first introduced in November 2016. The terminology can be a bit confusing. UL 9540 is a system listing, and is not for components. UL 9540A is a testing method, not a listing or certification. The combination of product standards and testing provide confidence in the safety of the systems for both authorities having jurisdictions and consumers.
Learn More
- Listen to this webinar to hear a California Fire Marshal and an advisor to a DOE national lab discuss the standards in practical terms.
- Read the informational bulletin from an Industry Working Group: UL 9540A Fire Test Standard for Battery Energy Storage Systems.
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Permit applications are on the rise for residential energy storage systems in jurisdictions across the country. In some cases, building departments are seeing these systems for the first time. The permitting and inspection of an energy storage system extends beyond just the National Electrical Code® (NEC). The permit application should be reviewed by the wiring or electrical inspector and also inspectors for building and fire code compliance.
- Hear Chief Michael O’Brian, Brighton Area Fire Authority, answer this question in a recorded webinar about what impacts the safety of ESS.
- Download a guide to multiple codes related to ESS Guide: Energy Storage Systems: Based on the IBC®, IFC®, IRC® and NEC®
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With the prevalence of energy storage systems (ESS), particularly battery energy storage systems (BESS), this question is asked by authorities having jurisdiction (AHJ) across the country.
For one-two family dwelling units, BESS are permitted for installation in detached garages/accessory structures, attached garages separated from the dwelling in accordance with International Residential Code® IRC® R302.6 (occupancy separation), and enclosed utility closets, basements, storage or utility spaces with finished or non-combustible walls. The BESS cannot be installed in habitable spaces of dwelling units including sleeping rooms, spaces opening directly into sleeping rooms and closets. If installed on the exterior of a dwelling unit, the ESS must be located at least 3 feet from doors and windows.
For commercial buildings, BESS are permitted for installation in any indoor area of the building, subject to size limitations, enclosure requirements, separation, ventilation, and fire detection and control. There are separate requirements for rooftop, exterior, and parking garage installations. For systems above 600 kWh storage capacity, a dedicated ESS building is typically required. NFPA® 855 is another standard for installation of stationary ESS.
Learn More
- View this recorded webinar to hear a discussion between a California Fire Marshal and an advisor to a DOE national lab on energy storage system safety. Recorded webinar.
- Take a mini-course about the basics of energy storage systems.
- Download a guide to multiple codes related to ESS Guide: Energy Storage Systems: Based on the IBC®, IFC®, IRC® and NEC® hear a discussion between a California Fire Marshal and an advisor to a DOE national lab on energy storage system safety.
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Looking for further information about high performance buildings, energy storage, solar, and more? Visit the Clean Energy Clearinghouse for an expanded list of expert resources and CEU’s:
Have questions, feedback, or suggestions for future resources? Contact us at [email protected].
The Interstate Renewable Energy Council (IREC) in partnership with the International Code Council, International Association of Electrical Inspectors, National Association of State Fire Marshals, Slipstream, FSEC Energy Research Center, Southeast Energy Efficiency Alliance, and Pacific Northwest National Laboratory assembled these resources to provide you with up to date, reliable, vetted information and training related to existing and emerging technologies.