Keith Lofstrom: Server-Sky — Solar Powered Server and Communication Arrays in Earth Orbit

Server Sky is a proposal to build large dispersed arrays of 3 gram paper-thin solar-powered computer satellites and launch them into 6400km earth orbit.

Thinsat arrays use unlimited space solar power and operate outside the biosphere. The environmental impact of power generation and heat disposal is tiny. Earth can return to what it is good at — green and growing things — while space can be filled with gray and computing things.

Besides the presentation of the overall system, we will discuss the astronomical and ecological consequences of very large solar collectors in orbit, and how Server Sky will minimize or eliminate them.

Keith Lofstrom is a mixed-signal integrated circuit designer in Beaverton, Oregon. He is CEO of SiidTech, which licenses silicon identification technology. He is active in the open source community, and 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.

It is easier to move bits than atoms or energy.

Server Sky thinsats are ultralight films of glass that convert sunlight into computation and communications. Powered by solar cells, propelled and steered by light pressure, networked and located by microwaves, and cooled by radiation into deep space. Arrays of tens of thousands of thinsats act as highly redundant computation and database servers, as well as phased array antennas to reach thousands of transceivers on the ground.

Traditional data centers consume almost 3% of US electrical power, and this fraction is growing rapidly. Server arrays in orbit can grow to virtually unlimited computation power, communicate with the whole world, pay for themselves with electricity savings, and greatly reduce pollution and resource usage in the biosphere.

The goal is an energy and space launch growth path that follows Moore's Law, with the cost of energy and launch halving every two years. Server Sky may cost two to ten times as much as ground-based computation in 2015, but is may cost 100 times less in 2035. The computation growth driven by Moore's Law is solving difficult problems from genetics to improved manufacture for semiconductors. 

If Server Sky and Moore's Law can do the same for clean energy, we can get rid of the carbon fuel plants, undam the rivers, and reduce atmospheric CO2 far sooner than we had dared hope. Energy production systems based on manual manufacturing, human construction assembly, and the use of terrestrial land, biological habitat, and surface water, packaged to survive weather, gravity, and corrosion, cannot grow at the same rate as Moore's Law.

For more information see his websites at: and

The most likely technical showstopper is radiation damage.

The most likely practical showstopper is misunderstanding.

Working together, we can fix the latter.