OnBeat, an apps and hardware startup run by the Glasgow-based Andreson family, has devised a pair of headphones that can store enough charge to fill up your phone, and then replenish themselves via a headband covered with 55cm2 of solar panelling. Why didn't anyone think of this before?
Enough charge to fill your phone, and then some
Lead designer Samuel Jones of Centreline Design told us at the CES Unveiled event in London (a precursor to the world's biggest tech show, CES Las Vegas, in January) that there's a 1200mAh battery squirrelled in each earcup, which totals 2400mAh of charge. That's sufficient to re-juice your iPhone 5s one and a half times, and if the solar cells fail you, you can charge the batteries using a built-in microUSB port.
The headphones' drivers are passively amplified, so use up none of the batteries' reserves. In fact, the headband and earcups are for now merely a mule for the additional electronics, although we're told that amplified designs with active noise cancelling could also be on the agenda.
In decent light conditions the poly-crystalline silicon solar cells are theoretically capable of recharging the daisychained batteries from empty in "about a day" (or less in bright sunshine), but more crucially, the 0.55W output should be enough to keep your phone's charge at a constant level.
£100-ish, out February-ish
As for sonic credentials, the On Beats feature a pair of 40mm drivers, and co-founder Frank Anderson promises that efforts have gone in to making them sound competitive for the asking price they're currently mulling over.
In the hand, it's clear the OnBeats are still at the prototype stage (they're a little rough round the edges), but there's a lot to like. They're quite smart, well padded and impressively light considering there's a pair of batteries inside.
If they're sufficiently polished up in time for launch in early 2014 and deliver on their audio promises, they could be a bit of a winner. Certainly, OnBeat has hit upon a very neat idea.
Want more solar gadget goodness? Try some ingenious ways to charge up your kit.