Mitsubishi Heavy Industries has almost finished designing its next-generation nuclear reactor, paving the way for construction to begin as Japan shifts its energy focus to develop more atomic power.

The Tokyo-based company can start building the facility once a site for it in Japan is established and some late-stage tests are completed, according to President Seiji Izumisawa. It will take about 10 years to construct and start operations.

"Once a site is decided, things will move forward,” he said in an interview on Friday. The hope is that a selection will be made "not too far in the future” so that knowledge and experience surrounding reactor construction can be passed to the next generation of engineers, he said.