It has been looking for ways to power its data center, and it realizes the benefits of wind power, such as zero fuel requirements, the opportunity to support the US economy more by buying US-built turbines, zero pollutant and greenhouse gas emissions, and a cost of 9.7 cents per kWh without government subsidies.
9.7 cents is a low cost; however, the implementation of energy storage increases it, and Apple will need energy storage or backup generators to compensate for power fluctuations, if they are to directly power their data center with it.
Apple’s wind energy storage concept involves using a wind turbine to rotate a shaft that turns a device that has one or more paddles, a propeller, or a drum attached to it and immersed in a volatile fluid.
Here is the patent application’s description of the process:
“Once sufficient heat is transferred to working fluid, the heat may be used to generate electricity. In particular, the heat may boil working fluid (e.g., due to the low boiling point of working fluid), generating vapor that is used to rotate a turbine. Turbine may then be used to drive an electric generator that supplies electricity to a load, such as a motor vehicle, home, business, building, and/or electrical grid. Transfer of heat from low-heat-capacity fluid to working fluid, as well as the resulting generation of electricity from the transferred heat, may be ceased once the energy stored in low-heat-capacity fluid is no longer needed to meet electrical demand.”
This may not be viable at the moment, but working on energy storage concepts for off-grid renewable power is a step in the right direction, especially for the long run.
This patent application was submitted back in June 2011. Who knows if Apple is still hopeful about the technology today? We’ll see.
Apple’s Green Gene
Apple hasn’t been the most open about its environmental effects, but it has actively promoted strong climate change policies on the government level, and it has produced some of the world’s most efficient computers, tablets, and phones. It has also used solar power for some of its needs, including America’s largest end-user-owned, onsite solar array for a LEED Platinum data center in North Carolina.