In this edition of V2G News, we tackle the industry’s great fork in the road—the AC vs. DC debate. This unresolved question of where the inverter lives, in the car or in the charger, is shaping costs, standards, and the very pace at which V2G can scale. Then, we turn to a groundbreaking global patent analysis that charts the trajectory of V2G innovation—revealing where the most inventive work is happening, who’s driving it, and how the field is maturing.

And as always, you’ll find Steve’s hand-picked top V2G stories from around the world—curated to keep you ahead of the curve in this fast-moving field.

V2G Insights

Highway to Scale: Why the AC/DC Debate is Slowing Down V2G

 “It’s a long way to the top if you wanna rock ’n’ roll.”

—AC/DC

Expectations are high for vehicle-to-grid (V2G) technology to unlock the massive storage potential of electric vehicles and support the clean energy transition. But a crucial and often underappreciated debate may be stalling its progress: should V2G operate primarily through AC (on-board) or DC (off-board) systems?

At the heart of this distinction is the inverter—the component that converts the direct current (DC) stored in an EV battery into alternating current (AC) used by the electric grid. In V2G-DC systems, this power conversion occurs in the external DC charging station, which houses a bidirectional inverter. In V2G-AC systems, the inverter is built into the vehicle itself, allowing energy to flow through a bidirectional AC charging port to buildings or the grid.

The AC/DC Debate

The AC vs. DC architectural choice has far-reaching implications for cost, efficiency, noise, and grid interconnection, as well as for how V2G functionality is coordinated. In both AC and DC systems, ISO 15118 generally specifies that commands originate from the vehicle side during standard charging. However, in dynamic operating modes—when real-time adjustments to charging or discharging are needed—the electric vehicle supply equipment (EVSE) typically controls the power flow, regardless of whether it’s an AC or DC system. This interplay between vehicle and EVSE control is central to how grid interaction and power export are managed in practice.

After numerous conversations with experts in the field, there is no clear consensus among industry stakeholders on which architecture—AC or DC—should dominate, and this unresolved debate is a barrier to scaling V2G. Some view V2G-DC as the clear winner for its efficiency and technical simplicity. Others argue V2G-AC is more scalable and consumer-friendly.

V2G Intelligence

Mapping the Innovation Landscape: What V2G Patents Tell Us About the Technology’s Trajectory

As vehicle-to-grid (V2G) technology transitions from concept to commercialization, patent activity serves as a clear barometer of its technological maturity. A groundbreaking study published in Renewable and Sustainable Energy Reviews, titled “Vehicle-to-Grid Energy Technologies: Patent Landscape Analysis, Technical Updates, and Innovations Towards Sustainable Transportation,” offers the first comprehensive global analysis of V2G patent trends.¹ By examining over 2,000 patents filed between 2008 and 2025, the researchers map the trajectory of V2G innovation—revealing where, how, and by whom this transformative technology is advancing.

A Surge in Innovation

As vehicle-to-grid (V2G) technology transitions from concept to commercialization, patent activity serves as a clear barometer of its evolution. The trajectory of V2G-related filings mirrors the broader shift from exploratory research to market-driven development. Early filings were sparse, reflecting a nascent field dominated by academic inquiry and technical speculation. But that changed dramatically in the past five years, as more companies began developing commercially viable V2G products and infrastructure.

Patent filings in the V2G domain have grown steadily—from single digits in the early 2010s to double digits annually between 2020 and 2023, with continued momentum into 2025. The spike in 2020 coincides with global clean energy investments spurred by pandemic recovery programs, while the 2023 increase aligns with key breakthroughs in bidirectional charging standardization and the emergence of V2G-ready EV platforms.

Notably, the filings have shifted from academic and government institutions to large technology companies and automakers, signaling a pivot toward real-world deployment. This surge reflects a maturing innovation ecosystem—where competitive positioning, IP protection, and market differentiation now drive patenting behavior, rather than purely exploratory research.

¹Maher G.M. Abdolrasol, M.A. Hannan, S.K. Tiong, Shaheer Ansari, Yanis Hamoudi, Pin Jern Ker, M.J. Hossain, Vehicle-to-grid energy technologies: Patent landscape analysis, technical updates and innovations towards sustainable transportation, Renewable and Sustainable Energy Reviews, Volume 224, 2025, 116142, ISSN 1364-0321,  ttps://doi.org/10.1016/j.rser.2025.116142.

V2G Finds

Tesla cars can now do vehicle-to-home (V2X) with this new Powerwall competitor

Tesla’s slow entry into the V2X space—limited to the Cybertruck’s Powershare feature and without full integration across its lineup—has created room for innovators like Sigenergy to step in. Sigenergy’s fully certified, modular energy storage system integrates a bidirectional DC charger capable of both charging EVs at up to 25 kW and pulling power from them to supply homes or the grid, using the ISO 15118 standard. Compatible with both CCS and NACS (via adapter) and tested successfully on a range of EVs, the system positions itself as a true Powerwall competitor by combining EV charging, home storage, and solar integration into one expandable platform. This kind of third-party innovation underscores how gaps left by Tesla’s cautious approach are being filled by agile players ready to unlock the full potential of V2X.

8/4/2025

State Grid Changzhou completes Jiangsu’s first V2G settlement

China continues to advance its leadership in V2G with a milestone achievement in Jiangsu province, where State Grid Changzhou completed the region’s first commercial settlement for vehicle-to-grid power exports. Three electric buses discharged 47 kWh to the grid during peak hours, earning a modest 18.38 yuan ($2.56) but marking the establishment of a full commercial process for V2G transactions. Enabled by new provincial pricing policies to support renewable integration and peak demand response, the project signals growing confidence in V2G’s commercial potential. As Jiangsu’s only pilot city, Changzhou plans to scale up through residential programs, large-scale discharging events, and public outreach—further cementing China’s role as a front-runner in turning EVs into valuable grid assets.

8/11/2025

ChargePoint and Eaton establish industry-first EV charging partnership

ChargePoint, one of the world’s largest EV charging networks, and Eaton, a global leader in intelligent power management, have announced a landmark partnership, which includes co-development of bidirectional charging and vehicle-to-everything (V2X) solutions. This collaboration will integrate chargers, electrical infrastructure, and engineering services into turnkey offerings for customers across the U.S., Canada, and Europe—simplifying deployment, reducing costs, and enabling EVs to power homes, buildings, and the grid. By combining ChargePoint’s EV charging expertise with Eaton’s deep capabilities in power distribution, the two established industry players aim to accelerate large-scale electrification and deliver seamless, scalable V2X-enabled charging solutions. While this announcement was first made in the spring, I felt it was important to highlight it here in V2G News, given the significance of two major industry leaders joining forces in the V2X space.

5/21/2025

GreenPower Secures $5M School Bus Contract

GreenPower Motor Company has secured a $5 million contract with the state of New Mexico to launch a two-year electric school bus pilot, deploying six zero-emission buses alongside Level 2 and Level 3 DC fast charging infrastructure, with a focus on testing vehicle-to-grid (V2G) capabilities. The program—supported by Highland Electric Fleets—will rotate buses through multiple districts, train drivers and mechanics, and evaluate grid resiliency, range, and charging performance. Featuring GreenPower’s high-capacity Mega BEAST with a 387 kWh battery and 300-mile range, the initiative exemplifies a key trend in the V2G market: leveraging DC fast charging in medium- and heavy-duty (MHD) fleet applications to unlock both operational and grid support value.

8/4/2025

Wallbox and the Rise of EV-Powered Virtual Power Plants: How a Bidirectional Charging Pioneer is Reshaping Grid Economics and Unlocking Passive Income for EV Owners

Wallbox’s launch of the Quasar 2—a UL 1741 SB–certified, ISO 15118-20–compatible bidirectional DC charger—marks one of the first low-power bidirectional DC products to reach the market, offering a bridge between the AC and DC V2G approaches explored in this edition’s AC/DC feature. Integrated with Wallbox’s new virtual power plant (VPP) platform in partnership with Leap, the current focus is on managed charging to optimize grid services and reward EV owners for shifting load. The move to true bidirectional export is the logical next step once regulatory and market barriers are addressed—positioning Wallbox to expand from VPP-enabled managed charging into full V2G capabilities that can power homes, support the grid, and bring consumer V2X into the mainstream.

7/31/2025

Nuvve Expands IP, Revenue, and Market Reach with Strategic Assets Acquisition of Fermata Energy

In one of the biggest V2G stories of the year—and one that hits close to home for me, having worked for both companies—Nuvve announced in the spring its acquisition of substantially all the assets of Fermata Energy, uniting two of the most advanced players in the V2X space. The deal combines Nuvve’s global grid aggregation and VPP expertise with Fermata’s proven behind-the-meter optimization, OEM integration, and certified charging hardware, creating an end-to-end V2G platform with expanded IP, customer reach, and revenue potential. Operating as “Fermata 2.0,” the integrated team will deliver intelligent bidirectional energy solutions for fleets, utilities, and OEMs, supported by AI-driven software, domestic manufacturing partnerships, and a decade of combined commercial deployment experience.

4/29/2025

Securing the Grid: Cybersecurity Innovations in V2G and EV Energy Exchange Systems

A recent deep dive by ARC Electric’s Abhinav Kalia highlights a critical but often under-discussed challenge for the V2G industry: cybersecurity. As EVs, chargers, utilities, and aggregators connect through protocols like ISO 15118 and OCPP, each communication point becomes a potential entry for cyber threats—from unauthorized charger access to ransomware targeting entire fleets. The article calls for a “security-by-design” approach, embedding authentication, encryption, secure updates, AI-driven anomaly detection, and zero-trust architecture into every layer of the V2G ecosystem. While regulators like DOE, NIST, and ENISA are starting to address these issues, the pace of innovation is outstripping policy development. This is a topic V2G News will continue to follow closely—because without robust cybersecurity, the promise of V2G at scale simply cannot be realized.

7/26/2025