Deep dive: Vehicle-to-grid (V2G) & bidirectional charging — the fastest-moving subsegments to watch

By the end of 2025, more than 1.2 million bidirectional-capable electric vehicles were on roads globally, yet fewer than 4% were actively participating in vehicle-to-grid programs, according to BloombergNEF's Q4 2025 EV grid integration tracker. That gap between hardware readiness and market activation defines the central tension in V2G today: the technology works, the economics increasingly pencil out, but the regulatory, interoperability, and aggregation layers needed to unlock value at scale are only now falling into place. For procurement leaders sourcing fleet electrification and energy management solutions in emerging markets, the subsegments moving fastest offer both the greatest opportunity and the steepest learning curves.

Why It Matters

The global EV fleet is expected to surpass 100 million vehicles by 2028, representing an aggregate battery storage capacity exceeding 5 TWh. That distributed energy resource dwarfs total global stationary battery storage, which stood at roughly 120 GWh at the end of 2025 (International Energy Agency, 2025). Unlocking even a fraction of that capacity for grid services could displace billions of dollars in peaker plant investment, reduce curtailment of renewable generation, and generate new revenue streams for EV owners and fleet operators.

Emerging markets face a particularly acute version of this opportunity. Countries like India, Brazil, Indonesia, and South Africa are simultaneously building out EV adoption infrastructure and modernizing power grids that suffer from chronic supply-demand imbalances. Vehicle-to-grid and vehicle-to-home (V2H) applications can address grid instability while improving the total cost of ownership for EVs in markets where electricity tariff structures and grid reliability create strong economic incentives for distributed storage.

The procurement implications are significant. Fleet operators making vehicle purchasing decisions today are locking in hardware for 8 to 12 years. Choosing vehicles and charging infrastructure that support bidirectional power flow adds 5 to 15% to upfront costs but can generate $1,500 to $4,000 per vehicle per year in grid services revenue or avoided energy costs, fundamentally changing lifecycle economics (Rocky Mountain Institute, 2025).

Key Concepts

Vehicle-to-grid (V2G) refers to the export of stored energy from an EV battery back to the electricity grid through a bidirectional charger. The vehicle acts as a distributed energy resource, providing services such as frequency regulation, peak shaving, demand response, and capacity reserves.

Vehicle-to-home (V2H) and vehicle-to-building (V2B) are narrower applications where the EV battery powers a home or commercial building during outages or high-tariff periods, without necessarily exporting to the wider grid. V2H adoption is outpacing V2G because it requires less regulatory complexity and delivers immediate, tangible value to the vehicle owner.

Bidirectional charging hardware encompasses both the onboard inverter within the vehicle (DC-to-AC conversion) and the external charging equipment (known as electric vehicle supply equipment, or EVSE). The CCS (Combined Charging System) and CHAdeMO standards both support bidirectional power flow, though the industry is consolidating around the ISO 15118-20 standard for bidirectional communication protocols.

Aggregation platforms are software layers that pool hundreds or thousands of EVs into virtual power plants (VPPs), optimizing charge and discharge schedules across the fleet to maximize grid service revenue while respecting individual vehicle owner constraints on state of charge, departure times, and battery degradation limits.

What's Working

Fleet V2G in Commercial Applications

Commercial fleets with predictable schedules represent the fastest-moving V2G subsegment because they solve the availability problem that limits consumer V2G. School bus fleets are the breakout use case. In the United States, the electric school bus fleet grew from approximately 2,500 units in 2023 to over 12,000 by the end of 2025, driven by $5 billion in EPA Clean School Bus Program funding. Highland Electric Fleets, which operates V2G-enabled electric school bus programs in 35 states, reported that participating districts earned an average of $3,200 per bus per year in demand response and capacity market revenues during the 2024-2025 school year (Highland Electric Fleets, 2025). Buses charge overnight at low off-peak rates and discharge during summer afternoon peaks when they sit idle for months.

In emerging markets, Olectra Green Tech in India deployed 1,500 electric buses across Hyderabad, Mumbai, and Pune by mid-2025. While full V2G integration awaits regulatory clarity from India's Central Electricity Regulatory Commission, Olectra's fleet management platform already optimizes charging schedules to avoid peak demand charges, saving fleet operators 18 to 22% on electricity costs compared to unmanaged charging (Olectra Green Tech, 2025).

V2H for Resilience in Unstable Grids

Vehicle-to-home is accelerating fastest in markets where grid reliability is poor and backup generation is already a significant household expense. In South Africa, where load shedding resulted in over 200 days of scheduled power cuts in 2023 and 2024, Rubicon EV partnered with Eskom to pilot V2H systems in Johannesburg and Cape Town. Participating households with bidirectional-capable EVs reported eliminating diesel generator fuel costs averaging 2,800 rand ($155) per month while maintaining power during Stage 4 load shedding events (Rubicon EV, 2025).

Japan remains the most mature V2H market globally, with over 180,000 V2H-equipped homes by the end of 2025. Nissan's LEAF-to-Home system, now in its third generation, enables seamless backup power during grid outages and time-of-use arbitrage that saves homeowners 40,000 to 80,000 yen ($270 to $540) per year. Following the 2024 Noto Peninsula earthquake, V2H-equipped households in affected areas maintained power for 36 to 72 hours using their EV batteries, generating significant consumer demand in disaster-prone regions (Nissan Motor Corporation, 2025).

Aggregation Software and Virtual Power Plants

The aggregation layer is where the most venture capital is flowing. Kaluza, a UK-based platform spun out of OVO Energy, manages over 500,000 connected EVs and heat pumps across Europe, optimizing charging schedules to provide National Grid ESO with 150 MW of flexible capacity. Kaluza raised $72 million in Series B funding in early 2025, valuing the company at $430 million. The platform's machine learning algorithms predict individual vehicle usage patterns with 92% accuracy, enabling reliable capacity commitments to grid operators (Kaluza, 2025).

In the United States, Fermata Energy operates bidirectional charging installations at over 200 commercial sites, using its proprietary FermatAI platform to stack revenue from demand charge reduction, frequency regulation in PJM Interconnection markets, and demand response programs. Fermata reported average payback periods of 3.5 years on bidirectional charger installations in 2025, down from 6 years in 2023, as software optimization improved and PJM regulation market prices increased (Fermata Energy, 2025).

What's Not Working

Consumer V2G Adoption Remains Marginal

Despite the hardware being available in vehicles from Nissan, Hyundai, Kia, Ford, and BYD, consumer participation in V2G programs remains below 5% of eligible vehicle owners in every market. The barriers are partly economic: consumer V2G revenue typically amounts to $300 to $800 per year, which is insufficient to motivate behavior change or justify the $1,500 to $3,000 premium for a bidirectional home charger. Battery degradation concerns, though largely addressed by manufacturer warranties covering V2G cycling, continue to suppress consumer interest. A 2025 survey by J.D. Power found that 67% of EV owners cited battery health concerns as their primary reason for not enrolling in V2G programs, despite engineering studies showing that managed V2G cycling adds less than 2% additional degradation over a 10-year vehicle life.

Regulatory Fragmentation in Emerging Markets

Emerging markets face a patchwork of regulatory barriers that slow V2G deployment. India's electricity distribution companies (discoms) have no established tariff framework for energy exported from EVs back to the grid. Brazil's ANEEL (National Electric Energy Agency) published draft V2G regulations in October 2025 but has not finalized net metering rules for mobile storage assets. Indonesia's PLN (the state utility) prohibits non-utility generation exports entirely under current regulations, effectively blocking V2G. Even in markets with supportive policy frameworks, interconnection standards for bidirectional chargers are often absent or misaligned with international norms, forcing equipment manufacturers to seek country-specific certifications that add 12 to 18 months to market entry timelines.

Interoperability Gaps

The transition from CHAdeMO (which natively supports bidirectional power flow) to CCS and NACS connectors has created an interoperability gap. Tesla's NACS connector, now adopted by most major automakers for the North American market, does not yet support bidirectional power flow in production vehicles as of early 2026, though Tesla has announced V2H capability for the Cybertruck and next-generation Powerwall integration. The ISO 15118-20 standard, which defines the communication protocol for bidirectional charging, was published in April 2022 but has seen slow adoption by EVSE manufacturers. CharIN, the industry consortium promoting CCS and ISO 15118 adoption, reported that only 14% of CCS chargers shipped in 2025 were ISO 15118-20 compliant.

Key Players

Established Companies

Nissan: Pioneer in bidirectional charging with the LEAF platform, operating V2H and V2G programs in Japan, the UK, Denmark, and Australia since 2012.

Hyundai-Kia: All Hyundai Ioniq and Kia EV models manufactured from 2024 onward include Vehicle-to-Load (V2L) capability, with full V2G support via 800V architecture.

BYD: The world's largest EV manufacturer by volume, deploying bidirectional charging in fleet applications across China, Brazil, and Southeast Asia.

Enel X: Global energy services company operating V2G programs in Italy, Spain, the UK, and Chile, with over 30,000 connected bidirectional chargers.

Schneider Electric: Manufacturing bidirectional EVSE for commercial and residential applications, with ISO 15118-20 compliant hardware shipping since Q3 2025.

Startups

Fermata Energy: US-based V2G platform focused on commercial fleet applications, with bidirectional charger installations at over 200 sites.

Kaluza: UK-based EV aggregation platform managing 500,000+ connected devices for grid flexibility services.

Wallbox: Barcelona-based manufacturer of the Quasar series of bidirectional home chargers, deployed in 18 countries.

Nuvve: San Diego-based V2G aggregation company operating school bus and fleet programs across North America, with a proprietary GIVe (Grid Integrated Vehicle) platform.

dcbel: Canadian startup producing AI-driven bidirectional chargers with integrated solar inverter functionality.

Investors

Breakthrough Energy Ventures: Investor in multiple V2G and grid flexibility startups including Fermata Energy and Kaluza.

Energy Impact Partners: Portfolio includes investments in bidirectional charging and fleet electrification companies.

SUSI Partners: European sustainable infrastructure fund investing in V2G aggregation platforms and fleet-as-a-service models.

Climate Investment: Abu Dhabi-backed fund with active positions in V2G deployments across MENA and South Asian emerging markets.

KPI Benchmarks

Metric	Current (2025)	Target (2028)	Leading Performer
V2G revenue per vehicle per year	$1,500-4,000	$3,000-6,000	Highland Electric (school buses)
Bidirectional charger cost (residential)	$2,500-4,500	$1,200-2,000	Wallbox Quasar
Aggregation platform response time	2-10 seconds	<1 second	Kaluza
Round-trip efficiency (AC-to-AC)	82-88%	90-93%	Fermata Energy
Additional battery degradation from V2G	1-3% over 10 years	<1% over 10 years	Nissan LEAF
Fleet V2G participation rate	15-25%	60-80%	Highland Electric
Consumer V2G participation rate	2-5%	15-25%	Enel X (Italy)

Action Checklist

• Require bidirectional charging capability (ISO 15118-20 compliance) in all new fleet EV procurement specifications
• Conduct a site-by-site analysis of electricity tariff structures to quantify V2G and V2H revenue potential before charger deployment
• Evaluate aggregation platform vendors on response time, grid operator certifications, and battery degradation management algorithms
• Negotiate OEM warranty terms that explicitly cover V2G cycling without voiding battery warranties
• Engage local regulators early on interconnection standards and export tariff frameworks, particularly in emerging markets without established V2G regulation
• Pilot V2H capability for fleet depot backup power to build operational experience before committing to full V2G grid services
• Include battery state-of-health monitoring and degradation tracking in all V2G-enabled vehicle telematics contracts
• Map grid operator programs (frequency regulation, capacity markets, demand response) by jurisdiction to identify highest-value revenue stacking opportunities

FAQ

Q: Does V2G cycling significantly degrade EV batteries? A: Engineering studies consistently show that managed V2G cycling adds less than 2 to 3% additional degradation over a 10-year vehicle life compared to charge-only operation. The key factor is "managed" cycling: aggregation platforms limit depth of discharge to 20 to 80% state of charge, avoid extreme temperatures, and use C-rates (charge/discharge speeds) below 0.5C. Nissan, Hyundai, and BYD all offer warranty coverage that explicitly permits V2G cycling. The University of Warwick's 2025 study of 4,500 V2G-enrolled LEAFs in the UK found no statistically significant difference in battery capacity retention versus a matched control group of non-V2G vehicles after 5 years.

Q: What revenue can fleet operators realistically expect from V2G in emerging markets? A: Revenue varies significantly by market structure. In markets with established capacity or frequency regulation markets (such as India's proposed ancillary services market or Brazil's regulated reserve market), fleet operators can expect $800 to $2,500 per vehicle per year. In markets without formal grid service markets, the primary value comes from demand charge reduction and time-of-use arbitrage, which typically yields $500 to $1,500 per vehicle per year. The highest returns accrue to fleets with predictable idle periods (school buses, delivery vehicles parked overnight) and access to time-of-use tariffs with peak-to-off-peak price ratios exceeding 3:1.

Q: Which bidirectional charging standard should procurement teams specify? A: For new installations, specify ISO 15118-20 compliant CCS or NACS hardware. While CHAdeMO has the longest track record for bidirectional charging, the global industry is consolidating around CCS/NACS connectors, and all major automakers except Nissan (which continues to support CHAdeMO alongside CCS) have committed to CCS or NACS for future models. Ensure that the EVSE firmware supports Plug and Charge authentication (ISO 15118-2) and bidirectional energy transfer (ISO 15118-20). Request vendor documentation showing interoperability testing with at least three vehicle OEMs.

Q: How do emerging market grid conditions affect V2G equipment requirements? A: Emerging market grids often have wider voltage and frequency variations than developed market grids, requiring bidirectional chargers with broader operating tolerances. Specify chargers rated for voltage ranges of 180 to 270V (single phase) or 320 to 470V (three phase) and frequency ranges of 47 to 53 Hz, versus the tighter 220-240V and 49.5-50.5 Hz ranges typical in European-spec equipment. Additionally, grid protection requirements (anti-islanding, fault current contribution limits) vary by jurisdiction: engage local distribution network operators during the specification phase to avoid costly post-installation modifications.

Sources

• International Energy Agency. (2025). Global EV Outlook 2025: Scaling Up and Integrating. Paris: IEA.
• Rocky Mountain Institute. (2025). Bidirectional Charging: The Business Case for Fleet Operators. Boulder, CO: RMI.
• Highland Electric Fleets. (2025). V2G Performance Report: 2024-2025 School Year Results. Beverly, MA: Highland Electric Transportation.
• Olectra Green Tech. (2025). Electric Bus Fleet Operations: Annual Performance Review. Hyderabad: Olectra Green Tech Limited.
• Rubicon EV. (2025). Vehicle-to-Home Pilot Results: Johannesburg and Cape Town. Cape Town: Rubicon EV (Pty) Ltd.
• Nissan Motor Corporation. (2025). LEAF-to-Home V2H System: Performance Data and Disaster Resilience Case Studies. Yokohama: Nissan.
• Kaluza. (2025). Platform Impact Report: Grid Flexibility from Connected Electric Vehicles. London: Kaluza Limited.
• Fermata Energy. (2025). Bidirectional Charging Commercial Performance: 2025 Annual Report. Charlottesville, VA: Fermata Energy LLC.
• BloombergNEF. (2025). EV Grid Integration Tracker Q4 2025. London: Bloomberg Finance L.P.