Hoping to let you read in the sun for days, ebook reader maker Bookeen has created a new case for its Cybook Ocean ebook reader that lets you keep the battery topped up via the sun.

According to the company, the new cover can provide up to a days reading from just 1 hour in the sun meaning you'll probably never have to charge it again.

The new cover features "invisible" solar cells on the back. The solar cells are actually printed optical network combined with solar modules enabling to recharge the e-book thanks to photovoltaic effect (production of electricity thanks to a light source).

A reader that would expose outside their cover during an hour in good light conditions (25 000 lux and more) would give an adding day in battery autonomy for their ebook claims the company.

The new case will be available initially for the Cybook Ocean e-book this summer, in time for the summer holidays, before being extended to other devices from the company.

"This new cover for the Cybook Ocean has an invisible charging mechanism making your product almost autonomous. The product recharges itself without you noticing it. We benefit from the very weak energy consumption of our e-books and of the SunPartner technology, for this world premiere" explains Michael Dahan, co-founder and CEO of Bookeen.