The Renzan Hajokuri is still unknown to most of us! To my knowledge it absorbs energy from its surrounding to power itself, in our case the Spiritual Pressure is the Reishi of the Soul Society Itself!
It also releases a high beam which is able to destroy anything in that part! As seen in one of the pictures above, the beam is directed to one of the building and it totally obliterated it!
Thanks for reading! Make sure you fully watch the episodes and read the mangas! Probably out tomorrow!