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18 December 2020

Project i-rEzEPT works towards self-consumption and storage of locally generated renewable energy

irezept

In his interview with IMET, Kevin Hochstaetter, Section Manager for EV Integration & Infrastructure at Nissan Center Europe GmbH introduces the i-rEzEPT project and its contribution in demonstrating the societal benefits of EVs and bidirectional charging.

 

What is the project “i-rEzEPT” about?Kevin Hochstaetter

i-rEzEPT is a project funded by Germany’s Federal Ministry of Transport and Digital Infrastructure (BMVI). The project aims to show use cases of how electric vehicles that are capable of V2X technology (V2H, V2B & V2G) can improve the use of renewable energies while also reducing total cost of ownerships for vehicle owners. The cars themselves are able to charge bidirectional in order to enable Vehicle-to-Home (V2H), Vehicle-to-Building (V2B) & Vehicle-to-Grid (V2G) technology. 

In the project itself, we are working together with 13 individual households and a selected commercial fleet who we have provided in total 15 charging stations capable of bidirectional charging and 13 NISSAN LEAF.  

What is the scope of i-rEzEPT?

The aim of the project “i-rEzEPT” is to demonstrate the societal benefits of electric vehicles and bidirectional charging by reducing investment and operating costs of electric vehicles and charging infrastructure. In the project, NISSAN LEAFs will be used to:

-    participate in the frequency containment reserve market,
-    maximise the degree of self-sufficiency of fleets and individual households,  
-    move forward the sector coupling between mobility, electricity and heat through the development and elaboration of innovative new business models.

What was the reason for launching this project?

Basically electric vehicles are just “moving battery storages”. This means that as soon as an electric vehicle can feed electricity back from the car battery it can be used as a buffer storage. This creates an interesting use case by feeding overproduced energy – for instance from solar panels – to the vehicle. Cars remain unused around 95% of their time making them available for grid services most of the time. In German, we use a play on words in order to illustrate the use case of this project: The word “vehicle” means in German “Fahrzeug” which you can translate literally to “moving object”. Hence, we name vehicles after the main reason we use them. However, if you use your vehicle just 5% of the time it is not actually moving most of its time.Therefore, it is rather a “Stehzeug” (which literally means “non-moving object”) than a “Fahrzeug” (“moving object”). So why not just use them? This is something we want to find out and that is why we launched the project in the first place. 

"Electric vehicles are just “moving battery storages”. This means that as soon as an electric vehicle can feed electricity back from the car battery it can be used as a buffer storage."

 

Who are you working with?

NISSAN is part of a consortium together with Bosch Software Innovations GmbH, Fraunhofer Institute for Industrial Engineering (IAO) and Fraunhofer Institute for Manufacturing Technology and Advanced Materials (IFAM). NISSAN is taking the role of the consortium leader in this project providing electric vehicles (NISSAN LEAF), V2G charging stations and taking care of the overall project management. 

What kind of technology are you developing in this project?

Nissan’s vehicle-to-grid (V2G) technology is essential to the project. Moreover, the households require a solar system and a local energy management controller, which is developed specifically for the project by Bosch and Fraunhofer. This controller will monitor the households’ energy consumption. In theory, this will function as follows: Whenever the need for self-consumption is high, the controller decides to feed electricity from the vehicle to the house. On the contrary, when demand and prices for energy are high, the controller opts to market the vehicle’s energy via the frequency containment reserve market.

Further to this, the controller can also predict when a consumer will arrive and plug his car to the charging station. This is essential in order to make the right decisions about when the electricity from the vehicle should be fed to the house or to the energy grid. With this, we want to enable as much flexibility for consumers as possible. 

What are the expected outcomes and the potential benefits of i-rEzEPT for consumers and cities?

The project itself is still in progress and we are now launching the monitoring phase. What we expect on a short-term view: A key factor to make this use case work is to allow consumers being as flexible as possible. What will happen if you have to drive somewhere spontaneously? What if you need to take a longer route than expected? We want to find answers to these questions and proof that consumers should not worry about this while reducing investments and operating costs for them. 

On a long-term view our expected outcomes are to revolutionize the electricity market by decentralizing the energy grid and giving energy consumers more autonomy by being able to use more of their self-produced energy.

"What we expect on a short-term view: A key factor (...) is to allow consumers being as flexible as possible. (..) On a long-term view our expected outcomes are to revolutionize the electricity market by decentralizing the energy grid and giving energy consumers more autonomy by being able to use more of their self-produced energy."

Therefore, our aim is: Enabling to self-consume, store, and sell surplus energy generated by local renewable energy. From a consumer’s point of view this will significantly reduce investment and operating costs of electric vehicles and charging stations. Reducing the total cost of ownership of electric vehicles is hence the citizens’ main return on investment. For cities, the potential benefit is clearly the positive impact on air quality and the environment by reducing CO2-emissions.

In addition to mentioned benefits for cities and consumers, the return on investment for industries is the development of new business models and additional revenue streams, which can potentially create a competitive advantage for companies that pursue this strategy.

What are your recommendations to policy makers?

To support the industry, engage citizens and remove legal blocking points on the way to make this technology accessible for everyone. 

The biggest challenge for us in this project are the legal restrictions of V2G-services, which means that you’re not allowed to feed the electricity back to the public grid. So first, we need to enable V2G-services on a legal basis. In order to do this we need more partners from the energy industry opening up for this technology. The role of the policy makers should be to support industries investing time and money for this technology. A first step would be more subsidies for smart charging infrastructure that is capable of bidirectional charging. What we can also recommend is to engage citizens in this process.

"(...)more subsidies for smart charging infrastructure that is capable of bidirectional charging. What we can also recommend is to engage citizens in this process."

When we first launched the lottery for individual households, we never expected such a large amount of people who wanted to participate in this project. From the feedback we got so far we have a large amount of people who are highly interested in this technology and believe in the potential of it. We should not exclude them but rather give these people a voice! Including them at the current stage will help us transitioning towards a sharing economy and sustainability culture.