Grid Codes for Smart Grid Integration

The transition to #renewableenergy is accelerating across the globe—and at the heart of this shift lies the Battery Energy Storage System #BESS. While performance and capacity often steal the spotlight, it's the silent framework of #safetystandards and compliance protocols that make these systems reliable, scalable, and grid-ready. Let’s unpack what goes into making a truly safe, standards-aligned BESS: 1. Cells and Battery Modules: At the most granular level, individual lithium-ion cells and #batterymodules must comply with rigorous standards such as: • UL 1642 – Focuses on the electrical, mechanical, and environmental safety of lithium cells • UL 1973 – Addresses battery systems used in stationary and motive applications • UL 9540A – Evaluates thermal runaway fire propagation in battery systems These certifications lay the foundation for risk-free operation by mitigating hazards right at the cell level. 2. Battery Racks: #Batteryracks are not just containers—they're engineered structures housing multiple modules. Certified under UL 9540A, racks must prove their resilience against thermal events, offering another critical layer of protection. 3. Power Conversion System: PCS is the brain that manages energy flow between the grid and batteries. It must adhere to UL 1741, ensuring compliance with #antiislanding protection, voltage/frequency limits, and communication protocols critical for grid integration. 4. Battery Management System & Communication Interfaces: This digital backbone monitors voltage, temperature, state-of-charge, and fault conditions. It follows a suite of certifications: • UL 1741 & UL 9540 • CSA C22.2 No. 340-201 • IEEE 2686, 2688 This ensures that the #BMS not only protects the system but also communicates effectively with utilities, fire protection systems, and SCADA platforms. 5. Fire/Gas Detection & Explosion Protection: Advanced detection and suppression systems must comply with: • NFPA 72 & 855, and the International Fire Code (IFC) • Explosion protection as per NFPA 13, 15, 68, 69 and IEEE 855 These ensure that any off-gassing, over-temperature, or arcing event is identified early, triggering mitigation before escalation. 6. Interconnection with the Grid: The BESS must synchronize safely and intelligently with utility networks using protocols defined by: • IEEE 1547 & 2800: These standards cover everything from voltage ride-through to cybersecure communications. 7. System-Level and Installation Compliance: Holistic safety comes from aligning with installation guidelines such as: • NFPA 70 (NEC) • UL 9540 for complete BESS certification • IEEE C2 (NESC) for utility-grade deployments These cover enclosure requirements, spacing, #thermalzoning, wiring, earthing, and egress pathways for emergency responders. I welcome conversations with peers, partners, and policymakers working toward a safer, smarter energy future. How is your team approaching layered safety and compliance in energy storage?

Your #EV is about to become a #powerplant. Not metaphorically — legally. The moment a BMW iX3 sends power back to the grid, it stops being a car and becomes a generator. And generators don't play by the same rules as consumers. In my latest Current Affairs article, I unpack the regulatory shift that most people in EV and charging haven't fully clocked yet: → Why AC and DC #V2G have completely different #compliance architectures, and why that changes who is responsible for #GridCode certification → What the EU's Requirements for Generators (#RfG) actually demands from a V2G unit (#FrequencyResponse, #ReactivePower, #InterfaceProtection) →  How Germany's #VDE4105:2026-03 — the world's first enforceable V2G grid code — is already shaping BMW × E.ON and Ford × Octopus deployments today → Why certifying a system under VDE 4105 means certifying the vehicle, cable, and wallbox as a single integrated unit — and what that means for scale The rulebook is ready. The wiring is almost there. Next up: how grid operator parameters actually travel from a control room into the on-board charger inside a vehicle — via OCPP 2.1 DER control messages and ISO 15118-20 Amendment 1. Sign up for my newsletter to not miss this update! 🔗 Full article in the comments. Please do share your real-world experiences with V2G deployments in the comments, I'm keen to hear about your success stories and challenges. ElaadNL Bjoern Christensen Marco Piffaretti

𝗛𝗮𝘃𝗲 𝘆𝗼𝘂 𝗲𝘃𝗲𝗿 𝘄𝗼𝗻𝗱𝗲𝗿𝗲𝗱 𝘄𝗵𝘆 𝘆𝗼𝘂𝗿 𝗽𝗲𝗿𝗳𝗲𝗰𝘁𝗹𝘆 𝗱𝗲𝘀𝗶𝗴𝗻𝗲𝗱 𝘀𝗼𝗹𝗮𝗿 𝗼𝗿 𝘄𝗶𝗻𝗱 𝗽𝗿𝗼𝗷𝗲𝗰𝘁 𝘀𝘁𝗶𝗹𝗹 𝗴𝗲𝘁𝘀 𝗱𝗲𝗹𝗮𝘆𝗲𝗱 𝗮𝘁 𝘁𝗵𝗲 𝗴𝗿𝗶𝗱-𝗮𝗽𝗽𝗿𝗼𝘃𝗮𝗹 𝘀𝘁𝗮𝗴𝗲? It’s frustrating. You’ve invested months in engineering, only to be told: “Not grid compliant.” But here’s the reality—without strict grid codes, our networks simply cannot survive. Imagine every power producer pushing energy at will, without studying the impact. The result? Unstable voltages, frequency collapse, blackouts. That’s why grid codes exist. What grid codes really mean for us as engineers and developers:   • They ensure that every new plant or industrial load doesn’t harm existing grid operations.   • The Utility defines which planning studies are required—these vary with project size, grid strength, and technology.   • Models matter. PSS®E or PSCAD models are often mandatory so the utility can run transient and stability checks.   • As renewable penetration grows, rules evolve—LVRT, HVRT, ramp-up/ramp-down limits, harmonic limits.   • Point of Connection (POC) compliance is critical. For inverter-based plants, reactive capability is usually required at the POC, not just at generator terminals.   • Large clusters bring shared problems—like harmonics—even if one plant alone seems “clean.” 👉 The bigger picture: grid code compliance isn’t just regulation. It’s about protecting the stability of the system we all depend on. For developers, it’s also the difference between quick approvals and endless disputes. Takeaway: Treat compliance not as a hurdle, but as an engineering discipline. Build it into your design early—it saves time, cost, and reputation later. What’s been your toughest grid compliance challenge—LVRT, harmonics, or reactive power at POC? Let’s discuss. Save time at approval stage—reach out to learn how we build compliance into designs early https://wa.me/919042342912 #powerprojects #gridcode #gridcompliance #renewables #powersystems

Grid Interconnection, Inverters and Grid Codes This is the fifth in a series of posts to build a bridge between the "expert V2G world" and the "non-V2G-expert world" and educate and address head-on the critical issues often raised with V2G. Question: “Is the EV/EVSE pair interoperable with the electric grid?” My last post focused on the interoperability between the EV and the EVSE using the same version of the ISO 15118-20 protocol. To achieve interoperability between an EV/EVSE pair and the electric grid, we must also look at what it takes to be allowed to inject power into the grid. In 2030, there will be millions of Distributed Energy Resources (DER) - EVs, Rooftop solar, Home batteries,..) connected to the grids. If these DERs act independently without living up to some pre-defined interconnection requirements, they risk making the whole grid unstable and unmanageable. In short, the DERs must become certified “Good Citizens of the Grid” before being connected to the grid. The term: Good Citizens.." was coined by David Hochschild and Patricia Monahan, California Energy Commission. It is also known under the rather technical name of Interconnection Rule 21 in California. For a DER (EV/EVSE pair) to be allowed to interconnect to the grid, it must support a set of technical requirements known as Grid Codes. An analogy is to think of an EVSE/EV pair needing a unique key to open the door (lock code) to the grid. Most DERs, injecting power into the grid, are changing DC power into grid AC power.  This is done by power electronics known as Inverters.   So, fulfilling the requirements to interconnect to the grid mainly falls upon the Inverter, whether in the EVSE (DC) or the EV (AC). Therefore, California has defined a Common Smart Inverter Profile (CSIP) that DERs must support to be connected to the distribution grid. Some examples of grid code support: 1.     If the grid frequency falls or rises for a shorter period due to a temporary disturbance. The DER must not disconnect from the grid immediately since this could further aggravate the event. They are supposed to – for a given time – continue operating. This is known as Frequency-ride-through. 2.     The same applies to high/low voltage (Voltage-ride-through). So, to be truly interoperable, the EV and the EVSE must: A. Be able to talk and understand each other using the same protocol and B. The EV/EVSE pair must be able to support the grid codes of the distribution grid. This is precisely what the new International Energy Agency Task 53 aims to achieve worldwide (www.Task53.org) by gathering a consortium of EV/EVSE/DSOs/Aggregators that collectively support fully interoperable bidirectional charging solutions. A follow-up post from @Marco Piffaretti will detail the first concrete step to ask experts for input on Gaps & Bugs in ISO15118-20 or Grid Codes hindering V2G interoperability. Note: The 11kW inverter pictured is from Watt & Wells. #Task53 #V2G #Bidirectional #IEA

𝐁𝐚𝐭𝐭𝐞𝐫𝐲 𝐄𝐧𝐞𝐫𝐠𝐲 𝐒𝐭𝐨𝐫𝐚𝐠𝐞 𝐒𝐲𝐬𝐭𝐞𝐦𝐬 (𝐁𝐄𝐒𝐒) 𝐆𝐫𝐢𝐝 𝐂𝐨𝐝𝐞 𝐂𝐨𝐦𝐩𝐥𝐢𝐚𝐧𝐜𝐞 𝐎𝐯𝐞𝐫𝐯𝐢𝐞𝐰 #BESS are required to comply with grid codes to ensure #safe, #reliable, and #efficient integration into the electrical network. #Compliance to grid code is critical for maintaining grid stability, particularly as the penetration of #renewable energy and #storage solutions continues to grow. While specific requirements vary by country, the following outlines the key aspects of BESS grid code compliance: 𝟏. 𝐅𝐫𝐞𝐪𝐮𝐞𝐧𝐜𝐲 𝐚𝐧𝐝 𝐕𝐨𝐥𝐭𝐚𝐠𝐞 𝐂𝐨𝐧𝐭𝐫𝐨𝐥 • #𝐏𝐫𝐢𝐦𝐚𝐫𝐲 𝐅𝐫𝐞𝐪𝐮𝐞𝐧𝐜𝐲 𝐑𝐞𝐬𝐩𝐨𝐧𝐬𝐞 (𝐅𝐅𝐑: #𝐈𝐧𝐞𝐫𝐭𝐢𝐚): BESS must respond rapidly to frequency deviations during under-frequency and over-frequency conditions. • #𝐒𝐞𝐜𝐨𝐧𝐝𝐚𝐫𝐲 𝐅𝐫𝐞𝐪𝐮𝐞𝐧𝐜𝐲 𝐑𝐞𝐬𝐩𝐨𝐧𝐬𝐞: BESS should stabilize frequency over a longer timeframe following disturbances, supporting other generating units. • #𝐕𝐨𝐥𝐭𝐚𝐠𝐞 𝐒𝐮𝐩𝐩𝐨𝐫𝐭: Maintain voltage levels at the Point of Common Coupling (PCC) by injecting or absorbing reactive power • 𝐕𝐨𝐥𝐭𝐚𝐠𝐞 #𝐑𝐞𝐠𝐮𝐥𝐚𝐭𝐢𝐨𝐧: Adjust reactive power based on grid voltage levels to support voltage stability. 𝟐. 𝐅𝐚𝐮𝐥𝐭 𝐑𝐢𝐝𝐞-𝐓𝐡𝐫𝐨𝐮𝐠𝐡 (#𝐅𝐑𝐓) 𝐂𝐚𝐩𝐚𝐛𝐢𝐥𝐢𝐭𝐲 • 𝐋𝐨𝐰 𝐕𝐨𝐥𝐭𝐚𝐠𝐞 𝐑𝐢𝐝𝐞-𝐓𝐡𝐫𝐨𝐮𝐠𝐡 (#𝐋𝐕𝐑𝐓): Remain connected during short periods of low voltage to prevent widespread disconnections. • 𝐇𝐢𝐠𝐡 𝐕𝐨𝐥𝐭𝐚𝐠𝐞 𝐑𝐢𝐝𝐞-𝐓𝐡𝐫𝐨𝐮𝐠𝐡 (#𝐇𝐕𝐑𝐓): Withstand short periods of high voltage without tripping. • 𝐆𝐫𝐢𝐝 #𝐒𝐭𝐚𝐛𝐢𝐥𝐢𝐭𝐲: Maintain operation during disturbances such as faults or sudden generation loss. 𝟑. 𝐀𝐜𝐭𝐢𝐯𝐞 𝐚𝐧𝐝 𝐑𝐞𝐚𝐜𝐭𝐢𝐯𝐞 𝐏𝐨𝐰𝐞𝐫 𝐂𝐨𝐧𝐭𝐫𝐨𝐥 • #𝐀𝐜𝐭𝐢𝐯𝐞 𝐏𝐨𝐰𝐞𝐫: Ability to inject or absorb active power on demand for applications such as peak shaving and energy arbitrage. • #𝐑𝐞𝐚𝐜𝐭𝐢𝐯𝐞 𝐏𝐨𝐰𝐞𝐫: Provide reactive power support to enhance voltage stability. 𝟒. 𝐏𝐨𝐰𝐞𝐫 𝐐𝐮𝐚𝐥𝐢𝐭𝐲 • #𝐇𝐚𝐫𝐦𝐨𝐧𝐢𝐜 𝐃𝐢𝐬𝐭𝐨𝐫𝐭𝐢𝐨𝐧: Comply with Total Harmonic Distortion (#THD) limits to prevent grid instability. • #𝐕𝐨𝐥𝐭𝐚𝐠𝐞 𝐅𝐥𝐢𝐜𝐤𝐞𝐫: Avoid causing voltage flicker or fluctuations that impact grid users 𝟓. 𝐎𝐩𝐞𝐫𝐚𝐭𝐢𝐨𝐧𝐚𝐥 𝐋𝐢𝐦𝐢𝐭𝐬 𝐚𝐧𝐝 𝐆𝐫𝐢𝐝 𝐏𝐫𝐨𝐭𝐞𝐜𝐭𝐢𝐨𝐧 • Operate within specified voltage and frequency ranges without #tripping. • Coordinate with grid protection systems to avoid interference during #faults. • Comply with limits on short-circuit current contribution for proper #protection coordination. 𝟔. 𝐑𝐞𝐬𝐩𝐨𝐧𝐬𝐞 𝐓𝐢𝐦𝐞 𝐚𝐧𝐝 #𝐑𝐚𝐦𝐩 𝐑𝐚𝐭𝐞𝐬 • Respond quickly to #frequency or #voltage deviations as per grid code requirements. • Adhere to defined ramp rate limits for #charging and #discharging to prevent #instability. 𝟕. 𝐒𝐭𝐚𝐭𝐞 𝐨𝐟 𝐂𝐡𝐚𝐫𝐠𝐞 (#𝐒𝐎𝐂) 𝐌𝐚𝐧𝐚𝐠𝐞𝐦𝐞𝐧𝐭 • Maintain SOC levels to ensure sufficient #capacity for grid events. • Implement #automatic #reserve requirements as specified by grid codes.

Battery Energy Storage Systems (BESS) must comply with various certifications and standards to ensure safety, performance, and grid compatibility. These certifications vary by region and application (residential, commercial, or utility-scale). 1. International Certifications & Standards Safety & Performance Standards ✔ IEC 62619 – Safety requirements for Li-ion batteries used in industrial applications. ✔ IEC 62477-1 – Safety requirements for power electronic converter systems. ✔ IEC 62933-5-2 – Safety requirements for grid-connected energy storage systems. ✔ UL 9540 – Safety standard for BESS, covering the complete system. ✔ UL 1973 – Safety standard for batteries used in energy storage. ✔ UL 1741 SA / SB – Certification for inverters in grid-connected storage systems. Grid Compliance & Performance ✔ IEEE 1547 – Standard for interconnection and interoperability of distributed energy resources (DERs) with the grid. ✔ IEC 61850 – Communication standard for smart grids. ✔ IEC 61000-6-3 / 6-4 – Electromagnetic compatibility (EMC) requirements. 2. Regional Certifications North America (USA & Canada) ✔ NFPA 855 – Fire protection standard for energy storage systems. ✔ NEC 706 (National Electric Code) – Electrical installation rules for BESS. ✔ California Rule 21 – Grid interconnection requirement for energy storage in California. Europe (EU) ✔ CE Marking – Ensures compliance with EU regulations. ✔ EN 50549-10 – Grid connection requirements for energy storage in Europe. ✔ UN 38.3 – Transport safety for lithium batteries. India ✔ CEA Regulations – Central Electricity Authority (CEA) standards for grid connection. ✔ BIS Certification (Bureau of Indian Standards) – Mandatory for energy storage batteries. 3. Fire & Thermal Safety ✔ NFPA 69 – Explosion prevention. ✔ IEC 60730-1 – Automatic electrical control for fire safety. ✔ FM Global 5-33 – Fire protection for lithium-ion battery storage.

New in open-source Electrisim: Reactive Power Capability (PQ diagram) We have added Reactive Power Capability analysis so you can build a PQ diagram at the point of common coupling (PCC). The tool sweeps active power, runs repeated pandapower AC load flows at each PCC voltage (pu), and plots Q_min / Q_max at the PCC—ideal for connection studies and grid-code checks. What you can do - Compare simulated capability with regulatory Q(P) envelopes on one chart - Work across several voltage levels in grid connection point (tabbed results) - See compliance when requirements are defined - Export CSV for reporting Built-in grid code templates (plus your own table): - Custom (manual table) — enter P, Q_min, Q_max yourself - ENTSO-E RfG – PPM Inner Envelope (EU minimum) - ENTSO-E RfG – PPM Outer Envelope (max TSO range) - VDE AR-N 4120 Var. 2 (Germany HV, ≥110 kV) - VDE AR-N 4110 (Germany MV) - Polish Grid Code IRiESP – Type D (≥110 kV) - Polish Grid Code IRiESP – PPM / Wind Farms - GB Grid Code (UK, National Grid ESO) - Spanish Grid Code P.O. 12.2 (REE) - Danish Grid Code (Energinet TF 3.2.5) - Italian Grid Code (Terna, Allegato A.68) if you want other grid codes implemente - write it in comment. If you work on renewables, grid compliance, or interconnection, this is meant to shorten the loop from single-line model → PQ curve → code overlay. Below is the example of non-compliant onshore wind farm model which is freely available at our website. Let me know in comments what would change in this electrical system to make it compliant. If you want us keep going developing open-source software - I invite you to subscribe to the Electrisim software.

Grid codes for inverter based resources work on a simple idea: a fault shouldn't cost you the plant. If voltage sags but stays above a defined floor for less than a defined time, the resource must ride through, stay connected, rather than trip. NERC PRC-029-1 codifies that floor as two voltage time envelopes: Table 1 for wind, Table 2 for everything else, including PV and BESS. Table 2 is more permissive, PV/BESS get more time to ride through than wind, which makes Odessa more striking, not less. The fault didn't test the limit. June 4, 2022, 12:59 p.m. CT: a surge arrester failed near Odessa, TX, causing a B-phase to ground fault on a 345 kV line. Protection cleared it in three cycles, 0.05 seconds. Table 2's minimum mandatory ride through at that depth is 0.32 seconds, 6.4x longer than the fault lasted. By duration alone, this was unremarkable. The generation loss said otherwise. 844 MW of synchronous generation tripped (333 + 202 MW at the faulted plant, 309 MW at a separate South Texas plant 450+ miles away). Separately, 1,711 MW of solar PV output unexpectedly collapsed. Total: 2,555 MW. Frequency nadir: 59.7 Hz. Why PV that was never asked to trip disappeared anyway. NERC traced much of the PV loss to momentary cessation: legacy inverters at one facility ceased current any time voltage dropped below 0.90 p.u. the top edge of Mandatory Operation, nowhere near the 0.10 p.u. Permissive floor where blocking is actually allowed. PLL loss of synchronism alarms were also logged. Odessa joined a pattern already flagged after the 2016 Blue Cut Fire and 2017 Canyon 2 Fire. What closes the gap. PRC-029-1 requires current exchange throughout the mandatory region, and explicitly excludes tripping for PLL loss of synchronism. Current blocking mode in the permissive region must restart within 5 cycles (83.3 ms) of recovery (R2.3.1); Real Power must fully restore within 1.0 s (R2.5). BES IBR facilities must prove compliance by October 1, 2026, three months out; non BES by January 1, 2027. On the visual: the envelope breakpoints, fault duration, R2.3.1/R2.5 timings, and Odessa figures are transcribed directly from PRC-029-1 and the NERC report. Per plant voltage/power waveforms aren't publicly published, so the fault/power curves shown are labeled illustrative, not a literal recording. Sources: NERC "2022 Odessa Disturbance" report; NERC PRC-029-1, Attachment 1 (R2.2, R2.3.1, R2.5, footnote 1); FERC Order No. 909. #PowerSystems #ElectricalEngineering #GridReliability #NERC #PRC029 #PowerEngineering