The new specification is expected to be finalised by the middle of this year.
"Its fast transfer rate and efficient protocol makes eSATA the highest-performing external mainstream storage connection," said Knut Grimsrud, SATA-IO president and Intel Fellow.
"Enhancing eSATA with power delivery will provide a new level of convenience to the designer and the end user.
"By eliminating the need for a separate power connection, customers can more easily expand their storage, making Serial ATA an even more attractive solution for mainstream storage applications."
The group hopes that the specification will open up new markets for portable storage devices.