Book the window seats. It depends on models of Shinkansen. Usually most of new trains such as Nozomi, Hayabusa, Komachi, Kagayaki, Hakutaka, etc. have sockets. Traditional Kodama, Hikari, Tanigawa and Toki may not have them. Most of the trains have sockets only at the window side (A or E seats).

Yes, you can charge your laptop on the Shinkansen, but the availability of outlets depends on the specific train model and your class of service. On the N700S and N700A models, which dominate the Tokaido and Sanyo lines, every seat in both Ordinary and Green Cars is equipped with a power outlet. In older models, outlets may only be found at the window seats (A and E) or at the very front and back of each carriage. These outlets provide standard Japanese AC 100V (60Hz) power, which is compatible with most modern laptop chargers, though you may need a flat two-prong adapter if your plug is different. In the luxury Green Cars and Gran Class, outlets are conveniently located in the center armrests. If you are planning to work throughout your journey, it is highly recommended to reserve a window seat to guarantee power access, as the Shinkansen is a premier environment for business productivity at 300 km/h.