Last April, Logitech partnered with ZAGG to release a rather smart iPad case with built-in physical keyboard. The company has now announced a new book-style case for Apple's tablet where the power for the included Bluetooth keyboard comes from batteries juiced up by built-in photovoltaic panels. The Solar Keyboard Folio won't help an iPad last any longer, though. Fortunately, Wireless NRG has developed a tough extended battery case for the iPad that also packs light-soaking cells on its flap that can keep the protected tablet going for up to ten days. The panels on both cases don't just rely on direct sunlight for power, as they can also take advantage of indoor light too.

Logitech says that when the NiMh batteries of its new Logitech Solar Keyboard Folio are fully charged, the Bluetooth 3.0 keyboard will be operational for two years (based on an average use of two hours per day) even if its dye-sensitized solar cells never get access to any light during that time. The 64 (U.S.) / 65 (EU) keys have 1.5 mm of key travel and the case provides two viewing angles for either typing or viewing comfort.

Compatible with the second and third generation of iPad, the 16.8 x 0.7 x 9.96-inch (428 x 17.8 x 253-mm) book-style case offers front and back protection for the enclosed iPad, auto wakes the tablet when it's opened, and places it in sleep mode when closed. It's available this month for US$129.99.

The Kudocase from Wireless NRG trickle charges the built-in 4mm thin 10,000mAh batteries when the photovoltaic ink panels are exposed to either indoor or outdoor light sources, which in turn tops up the iPad's battery at the required voltage. The company says that the case essentially extends the iPad's ten-hour battery life to an impressive 24 hours of continued use. Based on the same two hours per day average as above, it's claimed that the case can give up to ten days of tablet use before needing some charging attention.

The Kudocase can also be used to juice up other devices in addition to the iPad courtesy of a USB charging port. An included HDMI 1.3 adapter caters for watching content from the tablet on a connected big screen TV, monitor or projector.

As well as extending the iPad's battery, the Kudocase also affords the tablet some protection thanks to a hard shell outer housing made from biodegradable corn grain. It benefits from a number of different viewing angle possibilities and features a useful whistle locator which will beep when the user, well, whistles (although the feature can be turned off to avoid accidental activation).

Users who simply can't wait around for sufficient light to fully charge the high capacity battery pack will be pleased to find a mains power lead supplied with each case.

There's a Kudocase version for each of generation of iPad and a number of colors to choose from. It's available now for US$189.95.

Sources: Logitech Solar Keyboard Folio, Kudocase