In Menifee, California, a groundbreaking initiative has begun with the launch of six newly constructed homes that utilize electric vehicles to power their essential systems. This innovative approach employs the **Kia EV9** electric vehicle connected to a **Wallbox Quasar 2** bidirectional charger, creating a residential vehicle-to-home (V2H) system that is the first of its kind in North America. The homes can harness the EV’s **100-kilowatt-hour (kWh)** battery to maintain power during outages or when electricity prices soar.
The deployment is significant as it marks the first application of the **Combined Charging System (CCS)** standard in occupied homes in the United States. This standard is commonly used in both European and North American charging facilities. Since the project commenced in July 2023, the homes’ smart electrical panels have effectively managed two-way power flow, allowing for charging from both the grid and rooftop solar panels, while also enabling energy to be sent back to the home when necessary.
Scott Samuelsen, the founding director of the Advanced Power and Energy Program (APEP) at the **University of California, Irvine**, which is overseeing the two-year trial, stated, “This project is demonstrating that bidirectional charging with CCS can work in occupied homes. It’s a step toward vehicles that not only move people but also strengthen the energy system.”
A First in Bidirectional Charging
For over a decade, two-way charging has primarily been limited to Japan. The **Nissan LEAF-to-Home** program proved its feasibility after the **Tōhoku earthquake and tsunami** in 2012, but it relied on the CHAdeMO standard, which has seen limited adoption outside of Japan. Most automotive manufacturers in North America and Europe opted for CCS, which until recently, supported only one-way fast charging.
The Menifee project is particularly notable as it provides real-world data on a technology that has mostly remained in pilot phases. The combination of the **Kia EV9** and **Wallbox’s Quasar 2** can deliver up to **12 kilowatts** of power from the vehicle to the home, demonstrating the potential of electric vehicles to contribute to energy resilience.
While momentum for commercial V2H systems has slowed elsewhere, projects like Menifee’s are paving the way for future developments. Ford’s **F-150 Lightning**, for example, supports home backup through **Sunrun**, but the equipment is not compatible with CCS. Additionally, Ford has announced a production pause for the F-150, which has delayed expansion efforts. **General Motors’** **Ultium Home** system, which works with its various electric vehicles, is facing similar challenges.
In contrast, the Menifee homes are generating operational data in real households, showcasing how this technology can function in everyday settings.
The Importance of CCS
When electric vehicles first emerged, CCS was designed primarily for rapid charging from the grid to the car, focusing on reliable and standardized fast charging. This focus helps explain the differences between CCS public chargers, many rated at **350 kilowatts or more**, and CHAdeMO-based chargers, which typically max out at **100 kW** but can still provide home backup.
Initially, bidirectional operation was not included in the CCS standard due to safety concerns, potential grid interference, and added hardware costs. The original communication protocol linking EVs and charging stations, **ISO 15118**, did not facilitate power export. However, the **2022 update**, **ISO 15118-20**, introduced secure two-way communication, allowing CCS vehicles to supply energy to buildings and the grid.
The **Wallbox Quasar 2** residential charger incorporates this update through an active-bridge converter circuit that uses silicon-carbide transistors, enabling efficient bidirectional power flow. With a power rating of **12 kW**, it can support essential home loads such as heating and cooling, refrigeration, and networking, according to **Aleix Maixé Sas**, a system electronics architect at Wallbox.
Each Menifee home equipped with a V2H system integrates a rooftop solar array and a **13-kWh SunVault** stationary battery from **SunPower**. Under typical conditions, solar energy powers daily household needs and charges the stationary battery. On sunny days, the solar panels can also charge the Kia EV9’s battery.
During outages or when energy prices spike, the homes isolate themselves from the grid. Solar power and energy stored in the SunVault maintain essential systems, while the EV battery provides additional power if the outage continues.
Research conducted by UC Irvine over the summer revealed that the vehicle adds a significant resilience feature. “It can relieve grid strain, increase renewable utilization, and lower costs by supplying power during peak-rate hours,” Samuelsen noted.
The implementation of V2H systems also presents challenges for home builders and electric vehicle service equipment manufacturers like Wallbox. Utilities must adapt their infrastructure to accommodate the bidirectional power flow, requiring a reevaluation of interconnection procedures and energy pricing structures.
Looking Towards the Future
Analysts predict significant growth in sales for bidirectional-charging systems through the late 2020s as costs decrease and standards become more established. In areas prone to wildfires or severe weather-related outages, and where time-of-use pricing is steep, projects like Menifee’s illustrate a viable path toward using electric vehicles as substantial and flexible energy reserves.
As electric vehicle batteries become capable of supplying energy for homes as seamlessly as they do for transportation, the lines between energy suppliers and consumers are likely to blur, marking a transformative shift in how energy is generated and consumed.
