24/7 Green EV Charging

Empowering EV owners to choose the source of their vehicle’s electricity.



With the unprecedented growth of electric vehicle (EV) adoption, the e-mobility sector could become a significant demand for renewable energy. On the back of the successful launch of Energy Web’s 24/7 matching Software Development Kit (SDK), Volkswagen, Energy Web, and Elli cooperated in a Proof of Concept (PoC) to assess technical viability of using the technology to decarbonize EV charging. The purpose of the PoC was to demonstrate how Energy Web’s open-source Switchboard and 24/7 solutions could be integrated into Elli’s existing green charging app to enable granular matching between EV consumption and renewable generation. The PoC put the EV Owner at the center, allowing users to set preferences for electricity generation type and location that dictate the EV’s charging schedule and ensure real-time matching of consumption with locally sourced clean energy. The Energy Web Chain provided the trusted audit trail so that the EV owner can trace and prove the provenance of each kWh used to charge their EV’s battery.

Who is building the solution project?

Energy Web - Adapted their open-source 24/7 matching SDK to track the provenance of every EV charging event, powered by their Switchboard solution, resulting in the 24/7 Green E-Mobility platform.
Elli - A part of the Volkswagen group Innovation, Elli provided their existing smart charging app, and assisted with integrating 24/7 green charging functionality.
EV.Energy - App development partner of Volkswagen Group Innovation, provided the development work for integrating 24/7 Green E-Mobility Platform with the Elli smart charging app.
Volkswagen Group Innovation
- Provided the real-world renewable energy generators connectivity to their on-board smart-charging backend and use of the corporate electric vehicle fleet.

How does it work?

The solution works by first onboarding each generation asset, organization, EV owner, and electric vehicle via a decentralized identifier (DID) which allows them to prove their identity, securely exchange data, define system roles and access, and receive and transfer ownership of minted NFTs representing fractionalized Renewable Energy Certificates. This Identity and Access Management is powered by EW’s Switchboard solution, which maps ownership of DIDs (i.e. EV Owner’s DID owns EV’s DID) and defines permissions which governs how they can interact with the platform.

Generation data from smart meters connected to participating generation assets is securely fed to the 24/7 Green E-Mobility platform every 15 minutes. The VW Smart Charging App and on-board back-end within the electric vehicles are also securely integrated with The 24/7 Green E-Mobility Platform. The user (EV Owner) is empowered to create a priority list of each available clean energy generation asset by inputting their preferred electricity generation type (e.g. solar, wind, thermal) and desired proximity (e.g. within a 5 km radius).

How does it work?

When the EV is connected to a charge point, the EV owner dictates their desired state of charge at the end of the charging session and end time / date and initiates the charge session within the Smart Charging app. The Green E-Mobility platform’s matching algorithm then utilizes all the available data to determine the optimal charging schedule to maximize usage of clean, locally sourced electricity. The generated and consumed electricity is matched at 15 minute intervals, with the algorithm automatically updating the schedule to reflect changes in projected generation patterns or the battery’s state of charge.

Once the electricity consumption is settled, a smart-contract deployed on Energy Web’s test network, Volta, issues an ERC1888 NFT, which is a fractionalized renewable energy certificate, proving the provenance and volume of clean electricity generated and consumed. The token is minted to the DID of the generation asset and transferred and retired to the DID of the EV owner. The EV owner is able to view their NFT certificate in the Elli app (as well as on the blockchain), along with a session summary of their charge session, which displays the breakdown of electricity source consumed as well as carbon intensity of their session in grams equivalent of emitted CO2. The session summary is facilitated by accessing an API which feeds in the local grid’s carbon intensity data.
Link to UI designs

Case Study for 24/7 Green Charging Steps:


Generation assets, organizations, EV owners and EVs are onboarded to the platform via their own DIDs and corresponding role definition on Switchboard


Secure data channels from generation assets, EVs and smart-charging back-end to the 24/7 Green E-Mobility platform


EV owner inputs their electricity source preferences into the Smart Charging app (energy type and plant proximity)


EV owner inputs their desired state of charge and predicted end date and time of the charge session, and initiates the session via the Smart Charging app


24/7 Green E-Mobility platform algorithm utilizes forecasted, and real-time generation data combined with consumer preferences to set the optimal green charging schedule


Generated and consumed electricity is matched at 15 minute intervals and the settled matching result triggers the issuance of renewable certificate NFTs via a smart contract deployed on Energy Web’s Volta network


A session summary is available to the EV owner in the Smart Charging app for each charge session and presents the electricity source breakdown, CO2 emissions and NFT certificate with a link to the blockchain transaction.


EV Owners are empowered to choose the type and location of the generated electricity which charges their electric vehicle’s battery
Granular electricity procurement promotes manageable integration of intermittent renewable energy resources, supporting existing grid infrastructure while reducing curtailment of production capacity.
Transparency into the provenance of consumed electricity and the environmental impact of each charge session highlights the importance of maximizing the use of clean energy wherever possible
Local generation asset owners benefit by promoting the availability and environmental benefits of utilizing their production
A traceable and secure audit trail powered by the Energy Web Chain ensures generators and consumers can clearly prove their environmental footprint
Potential for future interoperability e.g. utilizing Energy Web’s Open Charging Network (OCN) would open the platform to any integrated public charging point

What’s next

Volkswagen Group Innovation and other EV manufacturers and generation asset owners are exploring how they can roll out the solution to a wider market, ensuring as many EV owners as possible are able to benefit from choice in and traceability of their consumption.
Integration with various systems of Energy Attribute Certificates (EACs): The NFTs issued by the platform represent fractionalized renewable energy certificates, however, are currently not integrated with energy attribute certifying systems. The market currently lacks a clear and readily available standardization framework and issuance registry for granular temporal matching, however recognition of the need for such a system has soared in recent years and months. Energy Web looks forward to incorporating such standards into the solution in the near future and integrating directly with respective registries upon availability.

Incorporating local-grid mapping: This PoC implemented a simple geographical radius from EV charge point to generation asset connection point. Since the platform utilized VW’s generation assets and the charged points were known to be connected, the radius was sufficient. However, when rolling this solution out to the wider market, in order to ensure that the generation asset’s electricity would be consumed by local consumption assets, the platform would need to understand the relationship between local grid connection points and verify that the points operate within the same distribution grid infrastructure. Since this PoC utilized VW’s generation assets and the charged points were known to be connected, the radius was sufficient.

Download an overview of the 24/7 Green EV Charging case study in PDF