MIT Technology Review: Because of the complex hardware, permitting, and technical expertise required, rooftop solar panel systems have been prohibitively expensive to install. But a new, simplified system designed by the Fraunhofer Center for Sustainable Energy Systems may change all that; it has flexible panels with an adhesive backing and an innovative power distribution arrangement. The lighter design should allow homeowners to install the panels themselves by simply gluing them to the roof and hooking them up via a series of quick-connect cables. The power will be controlled and distributed via packet energy transfer (PET), an innovative electrical system being developed by the Rhode Island startup company VoltServer. The system is being marketed as much safer than conventional power delivery because its software performs safety checks and can cut off or reroute the power instantly if it senses a problem. The system is currently in the beta testing phase.