Toshiba proposes a "charging grid" system solution to promote the popularization of electric vehicles and solar power generation

Toshiba proposed a "charging network" scheme for a distributed charging and discharging equipment system at the "Smart Grid Exhibition" (June 16-18, 2010, at the Tokyo Big Sight Center in Koto Ward, Tokyo) (Figure). This system can use the surplus power provided by solar power generation to charge rechargeable batteries, and can be used for purposes such as fast charging of electric vehicles. Distributing this system in various regions will promote the popularization of electric vehicles and solar power generation.

Figure: The composition of the "charging grid" system. (Click to enlarge)

The charging network system consists of a bidirectional inverter, lithium-ion rechargeable batteries, and a fast charger. The power distribution system of the power company and the lithium-ion rechargeable batteries are connected together via the bidirectional inverter, and the fast charger is connected to the wiring connecting the two (lithium-ion rechargeable batteries and bidirectional inverter).

In this way, cheap nighttime electricity provided by the distribution system and surplus electricity from solar power generation systems installed in residential areas can be stored in lithium-ion rechargeable batteries. This electricity can be used for rapid charging of electric vehicles or during power outages. After installing this system, there is no need to implement substation boosting projects, etc., which can reduce the cost of installing a rapid charger (although the configuration of lithium-ion rechargeable batteries still costs money). This makes it easier to install a rapid charger.

In addition, the charging network system is also conducive to the effective use of surplus power from solar power generation. Since the voltage of the distribution system will increase when the surplus power provided by solar power generation is transmitted back to the distribution system, the current method is to stop transmitting the surplus power back to the distribution system when the voltage of the distribution system reaches a certain value. With this system, the surplus power provided by solar power generation that is not transmitted back to the distribution system and is wasted can be stored.

Toshiba aims to make the system practical within a few years. In addition to selling the system, the company is also considering providing related services.