Having worked on the composite bodys electrical grounding wiring, that plane is the most well grounded same electrical/static noise floor for any component anywhere in the plane. It's not composite rubbing on each other.
The electrical system is also one of the most advanced and highest power ever built.
There are six starter generators on each Boeing 787: two auxiliary starter generators on the Hamilton Sundstrand-supplied Auxiliary Power Unit (APU), and two variable frequency starter generators (VFSGs) mounted on each Trent 1000 main engine.
An integral part of Hamilton Sundstrand's 787 Electric Power Generating and Start System (EPGSS), the
generators collectively supply nearly 1.5 megawatts of power, which is enough to power about 400 homes, and more than five times the electric power on a current Boeing 767. Combined with the elimination of the high pressure pneumatic system, this results in an overall reduction of power required at cruise.
PR Newswire (
http://s.tt/1sMzm)
Taking a Peek into Boeing 787 Electrical Power System | The Skyward Blog
AERO - Boeing 787 from the Ground Up