The Cluster Saga (3 book series) [amazon.com]
by Carlos R. Tkacz (Author)
From Book 1: The 25th century. Humanity has discovered a new form of energy, the Source, derived from the very basis of life itself. Using this power to travel instantaneously through space, humans have spread through their corner of the galaxy and coalesced into two groups: the Coalition and the Inner Cluster. They are held in an uneasy economic and cultural relationship by their reliance on each other, the Coalition with the technology of the Source and the Inner Cluster with the materials to make it a usable form of energy. When rumors of conquest, political undergrounds, and alien contact threaten this balance of powers, it falls to three individuals to find the truth of the conspiracies swirling through their governments and to stave off a disastrous war. What they find in the process will change the course of humanity forever.