The Japan electricity market was deregulated at the start of April. Now instead of using Tepco, you can switch to a huge range of alternatives - Tokyo Gas, Eneos Denki, Shell, Looop Denki, Softbank etc.
There are tools like the following that tell you how much you can save by switching:
Additionally, if you're not a fan of nuclear energy or fossil fuel produced energy, you can choose a "greener" power company.
Has anyone had any experience with switching? Was it easy? How much do you expect to save?