[1][2] This series will be used as a test unit to collect data for future development and deployment of fuel cell vehicles.

Starting in 2021, JR East will conduct trials on the Tsurumi and Nambu lines and expects to have the technology ready for commercial application by 2024.

On 4 June 2020, the company announced that it would invest ¥4 billion into the development of this series, which is the new generation of the Fuel Cell New Energy Train experimental unit.

The train is painted in a blue splash pattern to represent the moistening of the earth and the water generated from the fuel cell device.

[2] The main goal of this project is to create a rolling stock that operates using clean energy, such as hydrogen, to minimize the environmental impact.

[5] JR East plans to implement fuel cell rolling stock on from fiscal 2030 for use on traditionally diesel-operated services.

[6] The FV-E991 series unit was delivered from the Japan Transport Engineering Company (J-TREC) factory in Yokohama in February 2022.