"It's not replacing staff but the bookcases mean we don't have staff behind the desks scanning returned books. We have been quite desk-bound but this means we can have one person behind the desk to serve customers and another person, who would previously have been behind the desk, out in the library to help customers in different ways."
Mr Keene said the technology cost "basically what a staff member would cost" and would be cost-neutral within four years. The technology has a 10-year lifespan.
The RFID system has also been added to the library's CDs, DVDs and other materials.
Library performance manager Sonny Tamihana said staff and customers were still getting used to the bookcases dealing with returned books.
"It's so different to how we are used to operating," Mr Tamihana said.
"The idea that a bookcase can do it for you is quite a mental leap."
The bookcase system has eight shelves that can hold up to 400 items at one time.
The Davis Library also has three new self-checkout kiosks where people can issue their own books.
"We had self-checkout before but these are better than the previous machine," Mr Keene said.
"They are as simple to use as an ATM machine which most people are used to. If it wasn't simple, it wouldn't work."
The self-checkout kiosks have audio, visual, touch and text features, with large screens that allow space for library promotions and recommended reads, and enable users to pay fees and charges.