Is wind power ready for data centers?
Damn that fracking natural gas! With natural gas prices at levels last seen a decade ago thanks to fracking shale deposits, electrical utilities are building small natural gas fired generating plants to help with peak loads. This is also good news for consumers who use natural gas for heating and cooking, and for a reduction in greenhouse gas and air pollution (Sulfur Dioxide, Mercury) emissions since natural gas produces significantly less than coal or oil. However, because the cost of generating electricity has been reduced or stabilized, green generated electricity has to compete with a lower market price, making alternative and renewable energy return on investment (ROI) longer and projects less likely to be funded in the highly competitive, cost sensitive data centers.
US EIA graphs showing projected increases in shale gas production and increased use by electricity generators from 1990 to 2035. Increased supply and resulting low prices of shale generated natural gas coupled with relatively low emissions compared to coal or oil means higher consumption by electrical generators for the next two decades.
The longer ROI has not deferred leading companies like Google and Apple from using solar, geothermal generated electricity, or fuel cells to supply their flagship data centers. Many data centers contract for green sourced electricity from the local grid to reduce their carbon footprint, but the actual electrons going through their servers is likely to be produced by coal or natural gas fired generating plants. Earlier pieces in this series looked at these and other energy sources such as cogeneration, batteries and microturbines for data centers. It is now time to examine wind as a useful or not so useful source for data center power.
Wind energy has been around a long time, from propelling boats across the sea to the famous windmills we see in Holland. Modern adaptations of these technologies have led to modern, computer generated airfoils designs to generate electricity and power sailboats.
Dutch windmills take advantage of abundant winds in The Netherlands to mill grains. Fitted with sails, these structures could turn the wind’s energy into rotary motion to power millstones during the grinding operation. Left Image Source Right Image Source
Windfarm on the coast of The Netherlands (Left Image Source) can generate enough power for 10,000 households. Interior (Right Image Source) shows mechanical and electrical components, most importantly the generator. Computer control of turbine blades for various wind conditions is crucial to safe and efficient operation.
Wind turbines employ airfoil designs in their blades along with modern materials to make them lightweight and strong. Thousands are in use built by major companies such as GE and Siemens as well as a host of others. Design, manufacture, installation, operation and maintenance are all well understood. Standing 80 meters (262 ft.) tall and fitted with 50 meter (164 ft.) rotor blades, these machines are made to pump out between 1.5 MW and 4.5 MW in a 45 km/hr (30 mph) wind and cost around $1 Million/MW (€0.8 Million/MW). These generators are able to power 2,500 US homes when the wind is blowing, and as parents wanting to take their kids kite flying know, a steady wind is the issue.
Part 2 of the promise of wind power will look at economics for data centers.