Hot dry rock geothermal energy as a separate state from that of the continuum of permeable rock—just as one would consider a completely closed faucet as distinct from one that is open to any degree, whether the flow be a trickle or a flood. In the same way, HDR technology should be regarded as totally distinct from EGS. A definitive book on HDR development, including a full account of the experiments at Fenton Hill, was published by Springer-Verlag in April 2012. Hot dry rock geothermal energy Hot dry rock (HDR) is an abundant source of geothermal energy available for use. A vast store of thermal
Duke Energy Center for the Performing Arts Duke Energy Center for the Performing Arts Duke Energy Center for the Performing Arts is the main venue for the performing arts in Raleigh, North Carolina. The naming rights to the center currently are held by Duke Energy (formerly Progress Energy), which purchased them from the city in 2005 for a 20-year term at the cost of $7.5 million. The original naming rights previously were held by Business Telecom, Inc. (now EarthLink)), and the facility was known as the BTI Center for the Performing Arts from 1997-2005. BTI Owner Peter Loftin donated $3.1 million to the center in 1999, matching