In April 2003, JR East, in partnership with the Railway Technical Research Institute, introduced the “New Energy Train” powered by a diesel hybrid system. It was based on the E127-100 class two-car EMU and was officially designated the KiYa E991. The single railcar with two driver's cabs combined a diesel engine with electric power transmission and lithium-ion batteries and was the world's first railcar with this type of drive. The findings from the tests were used to develop the two-car KiHa E200 hybrid multiple unit.

In 2006 it was converted into the KuMoYa E995, in which the diesel engine was replaced with a fuel cell. The diesel tank was replaced with six hydrogen tanks with a total capacity of 270 liters. In addition, the capacity of the batteries had been increased. The railcar was also tested in this form in daily operation in 2007, but there was no series production,

In 2009, the vehicle was rebuilt again, with larger batteries and a pantograph instead of the fuel cell. The batteries could be charged while driving via the overhead line and then up to 50 kilometers could be covered on non-electrified routes. At the time when test operations were conducted entirely on non-electrified lines, a stationary charging facility was built with a fixed conductor above the track. In this form, the vehicle formed the basis for the two-car EV-E301.

The HB-E210 is a diesel hybrid multiple unit for use in commuter traffic on the Senseki-Tōhoku line The KiHa E200 hybrid train was used as a basis, but this is built for use in rural areas. Adjustments therefore had to be made, especially in the interior. Eight two-car sets were built and have been in use since 2015.

The powertrain works on the same principle as the E200. Each car has a 331 kW diesel engine and batteries with a capacity of 15.2 kWh. Since it is a serial hybrid, the engine always charges the battery directly, which is also charged via recuperation when braking. The two traction motors per car are then always powered by the battery.

The HB-E300 is one of the so-called resort trains, which are used to undertake excursions on routes that are attractive to tourists. It is based on the E200 hybrid railcar, which was only built three times. There is a 331 kW diesel engine in each car, which is supported by batteries and is only started when necessary.

A total of six sets of the HB-E300 were built, half of which consist of two cars and half of which consist of four cars. Almost every train is used on a different line, only two two-car sets are used on the “Resort Asunaro” route, which were the first to be modernized in 2023. Depending on the line, the interior also has a dining car or compartments.