Abstract for Server Sky talk by Keith Lofstrom
Server-Sky: Solar powered server and communication arrays in Earth orbit http://www.server-sky.com
US data center power consumption in 2011 was around 120 billion kilowatt hours, or 3% of total US power consumption, and is expected to double every 5 years thereafter. Our work as programmers and technologists will continue this exponential growth. This will have huge environmental, social, and economic consequences unless we find alternative ways to power the digital economy.
Server sky is a proposal to build large dispersed arrays of 5 gram paper-thin solar-powered computer satellites and launch them into 6400km earth orbit.
A thinsat is a thin sheet of aluminum covered with thin film solar cells, with embedded processor, memory, and radio chips. Thinsats use light pressure for thrust and electrochromic shutters for steering. Thousands of thinsats position themselves in three dimensional arrays, about 100 meters on a side. An array acts as a large phased array antenna, permitting it to transmit thousands of communication beams simultaneously to ground receivers and other arrays in space.
A thinsat displaces 25 watts of ground-based electrical generation, cooling, and power conversion. A thinsat does not need the racks, cabling, power converters, land, buildings, and other infrastructure needed to build a ground-based server farm. These savings alone may pay for launch.
Thinsat arrays use unlimited space solar power, and operate outside the biosphere. The environmental impact of power generation and heat disposal is tiny. In time, new launch techniques, and solar cells made from lunar rock, can further reduce the environmental and economic costs of manufacturing and launch. However, there are other surprising ecological effects to study!
Earth can return to what it is good at – green and growing things – while space can be filled with gray and computing things.
Who is Keith Lofstrom? (http://www.keithl.com/)
Keith is an mixed-signal integrated circuit designer in Beaverton, Oregon. He is currently working on Server Sky, data centers in orbit, using large arrays of small, ultrathin satellites to turn space solar power into computing and data communications.
Keith invented the Launch Loop, a speculative space launch system, in 1981. It can be built with existing technologies and launch thousands of tons into orbit per day at costs below $5/kg.
Keith is active in open source and the Portland Linux Unix Group. Keith's server hosts the dirvish disk-to-disk backup program, based on rsync and written in Perl. Keith has a special interest in low power, high efficiency computing.
Keith has written for Kluwer Press, various IEEE journals, SysAdmin magazine, Liberty magazine, aerospace journals, and Analog .