Tofu-D .. 28 Gbps? That seems far too slow.
If only there was an article about it somewhere here.. https://www.nextplatform.com/2018/09/14/slicing-into-the-post-k-supercomputers-tofu-d-interconnect/
Fujitsu's Arm-based A64FX processor may have driven the most powerful supercomputer in the world, but it looks like its successor will be a more general-purpose chip that will focus on energy efficiency. The Japanese IT giant built its own Arm processor for use in the Fugaku supercomputer, and commercialized it in the PRIMEHPC …
will release a surplus of energy back to the grid while running?
Many vendors are actually considering abuse of the grid to make profit - basically get large batteries and store energy off peak and then sell energy off batteries during peak and make money on the difference.
That will potentially make it more expensive for people relying on off peak tariffs.