Apple has filed a number of patents for fuel cells that can be inserted into portable devices, such as laptops, without adding much weight.
One patent application, titled Fuel Cell System to Power a Portable Computing Device, says that due to environmental and geopolitical concerns there is an "increasing awareness and desire" for consumers to use renewable energy sources.
Fuel cells are interesting to Apple as they "can potentially achieve high volumetric and gravimetric energy densities" - or in layman's terms, pack a lot of energy into a small space. A successful cell would potentially enable continued operation of portable electronic devices "for days or even weeks" without refueling, the patent reads.
The patent lists a number of potential fuel sources including sodium borohydride and water, sodium silicate and water and lithium hydride and water. However, Apple concedes that it is currently challenging to design a hydrogen fuel cell in a cost effective way that is portable enough for use in a laptop.
Despite this green research and development, the Silicon Valley giant was recently lambasted by Greenpeace for using fossil fuels to power its data centers.
But in October, it emerged that Apple is quietly planning a solar farm near its newly opened, $1 billion Project Dolphin data center in Maiden, N.C. The Charlotte Observer reported that the local municipality has approved permits for Apple to reshape about 171 acres of vacant land that it owns across from the data center, for the purpose of building the solar array.
