Here’s an interesting take on green data centers: servers that use thermoelectrics to turn their own waste heat into power. Applied Methodologies Inc. has been working on the concept since 2007, and recently told Data Center Knowledge that it’s seeking funding — and an eventual partnership with a major server manufacturer — to bring its prototype Thermoelectric Generation System design to commercial production.
Right now, the Wantagh, N.Y.-based company says it will cost $10 to $20 per server to install its TGS systems, which can generate 10 volts and 5 amps at current efficiency levels. It will be interesting to see whether it can overcome the challenges in the century-old field of thermoelectrics, which consist of semiconductor materials that generate electricity when exposed to temperature differentials — that is, when one side is hot and the other side is cold. Traditional thermoelectric devices have used bismuth telluride, and have suffered from a key inefficiency — they also conduct heat, meaning that they quickly see temperatures equalize, losing their electricity-generating properties.
Most of the recent research into thermoelectrics has centered around using nanotechnology to design thermoelectric materials that conduct electricity but not heat. In March, researchers at Boston College and MIT announced that they had achieved a major thermoelectric efficiency increase in bismuth telluride by breaking it down and “rebuilding it in a composite of nanostructures in bulk form,” according to Boston College physicist Zhifeng Ren.
Other startups appear to be pursuing similar nanotechnology routes to more efficient thermoelectric devices. In May, Lawrence Berkeley National Laboratory spin-out Alphabet Energy landed a seed round of $1 million from Claremont Creek Ventures and the CalCEF Clean Energy Angel Fund to work on its thermoelectric materials, which it claims will be 50 times cheaper than existing materials, bringing its power generating costs to around $1 per watt. In March, Tucson, Ariz.-based Tempronics announced it had landed $2.7 million from investors including Nth Power for its technology to improve thermoelectric efficiencies of different materials, and MC10 and Photonic Devices have gotten ARPA-E grants to develop thermoelectrics from silicon nanotubes and nanowires, respectively.
As for where thermoelectrics can be put to most effective use, most of the companies in the field are targeting high-heat environments such as heavy manufacturing, automotive, aerospace and power generation. The U.S. loses roughly half of the energy it consumes to waste heat, according to U.C. Berkeley professor Arun Majumdar, providing a wide-open field for innovation to capture it beyond the simple mechanical waste heat generation systems out there today.
Whether or not thermoelectric can be made efficient enough to run at the relatively cooler temperatures that data center operators run their centers at remains an open question. But there’s no doubt that data centers are hot targets for energy efficiency innovation — according to Pike Research, global investment into green data centers will grow from $7.5 billion this year to some $41.4 billion by 2015.