Apple Inc. (NASDAQ:AAPL) may be known as a world leader in personal electronics, but unbeknownst to many the Cupertino, Calif. company is also in the business of developing alternative sources of renewable energy. Apple has invested in solar and natural gas “energy servers” at its Maiden, N.C. data center, and has also filed a patent for an “on-demand generation of electricity from stored wind energy.”
The U.S. Patent and Trademark Office received Apple’s (NASDAQ:AAPL) patent application in 2011 and published it Dec. 27. In the application, Apple Inc. proposes a wind turbine that generates electricity by converting heat energy instead of rotational energy created by the windmill’s blades.
The application notes that most wind turbines convert kinetic energy from wind into mechanical energy or electricity. But doing so relies on a steady supply of wind which, of course, is highly variable.
Apple (NASDAQ:AAPL) proposes to solve the problem of wind inconsistency with a system that instead converts the rotational energy from the turbine into heat, which can then be stored in a “low-heat-capacity” fluid. Once stored, heat can be transferred as needed in a “working fluid” to generate electricity during lapses of wind activity.
“The disclosed embodiments provide a system that generates electricity,” the patent application claims. “During operation, the system uses a set of rotating blades to convert rotational energy from a wind turbine into heat in a low-heat-capacity fluid. Next, the system selectively transfers the heat from the low-heat-capacity fluid to a working fluid. Finally, the system uses the transferred heat in the working fluid to generate electricity.”
The patent application notes that “on-demand” generation of electricity can reduce overall costs generally associated with variations in wind supply. The system can also be used in place of existing conventional energy storage devices such as batteries.
“Such on-demand generation of electricity from stored wind energy may additionally reduce costs associated with the operation of other power stations to offset fluctuations in electricity generation from wind power,” the patent application claims. “Along the same lines, the use of mechanical elements (e.g., rotation-transmission mechanism 104, blades 106), low-heat-capacity fluid 110, and friction to store the energy may provide cost savings over conventional energy storage mechanisms such as batteries and/or pumped-storage hydroelectricity. In other words, the system of FIG. 1 may facilitate the effective, economical, and/or reliable generation of electricity from wind power.”
Apple (NASDAQ:AAPL) is most likely interested in wind energy to ease the environmental and economic impact of its data centers. As more people store data remotely with services such as iTunes and iCloud, the data centers utilize an increasing amount of energy. Apple has already constructed a solar farm in North Carolina to power one data center and has also filed patents for hydrogen fuel cell designs that could power its devices.