Server farms use a lot of energy. How much, exactly? According to CNN, more than the entire auto industry does in producing cars and trucks. If the Internet were a country, it would be in fifth place for using energy and producing greenhouse gas.


Now some big server users are trying to turn their amp-guzzling ships around. Study that energy flow at left, and we'll get to it in a minute. Google says it wants to be zero emission, which is quite a feat considering that the company emitted 1.5 million tons of carbon dioxide in 2010 (the most recent year available). According to Fortune, Google’s 30,000 employees have a collective carbon footprint equal to that of the entire city of Fargo, N.D. (with more than 200,000 happy residents).


You may have seen that Google is going green with 395 electric car chargers in its corporate auto park. The company is working on autonomous driving (the motivation for that is a bit unclear, though it may be a whim of founders Larry Page and Sergey Brin) and also getting commuters onto 73 custom-built buses (free Wi-Fi!) so they don’t drive to work alone.


But it’s the servers that are the big hurdle. Servers run hot, so the cooling bill is huge. Google invested in BrightSource Energy, which is building a big solar thermal plant in the Mojave Desert, and AltaRock geothermal. I’ve long thought that the world’s server farms should be collectively relocated to Iceland, where electricity is practically too cheap to meter because of a) The tiny population; and b) The mega resources of both geothermal and hydro power. One drawback: those volcanoes. When Eyjafjallajokull went off in 2010, it stopped air traffic across Europe. The less-dangerous Grimsvotn followed in 2011.


Google’s energy investments aren’t huge considering the size of the company, but it has committed to buying 12 percent of its energy from green sources (wind and solar farms). What it hasn’t done is built its own eco-energy servers. And that’s why Microsoft’s latest move is intriguing. The company has a pilot program in Cheyenne, Wyo., that captures waste biogas from a wastewater treatment plant (the kind of stuff that’s normally flared off) and extracts hydrogen from that to power an electricity-producing fuel cell connected to a data center.


The key technology here is the anaerobic digester, also used at dairies to produce electricity from the cows’ methane. At wastewater plants, digesters accelerate the decomposing of organic material with specific microorganisms, producing methane biogas that is rich in hydrogen.  


Connecticut’s Fuel Cell Energy (FCE) makes gigantic molten carbonate fuel cells (like the one at right) that suck up that methane and produce utility-scale amounts of electricity, plus waste heat that can go back into the digesters (which work best when hot).


Wait, there’s more. According to Microsoft, “At the end of the process, we are still left with some CO2 as a byproduct of the fuel cell’s electrolysis. The quality of the CO2 is now high enough for reuse in industrial applications. In other words, the data plant will be turning a pollutant into a valuable commodity and transporting it for use by the marketplace.”


Chip Bottone, FCE’s CEO, tells me, “Data farms typically use enormous amounts of energy, so how do you power them responsibly? We’re using biogas as the main source of power, with the grid as backup — reversing the usual pattern you see. The intent is for the plant to be up and running around the middle of next year. The fuel cell is right next to the data center and the wastewater plant.”


Tony Leo, an FCE vice president, adds that data centers are usually run off the grid, with large generators as backup. In the aftermath of Hurricane Sandy, we can see how that sometimes doesn’t work out — the generators get flooded out along with everything else.


Bottone told me that FCE’s fuel cells produce electricity at around 15 cents per kilowatt-hour. “That’s fairly expensive, especially in areas of low-cost power,” he said. “But if we can avoid the need to buy big-ticket generators, the extra cost is offset. Plus, the power is very reliable — data centers lose a lot of money for every minute they’re down. It is grid connected, but it can also operate without the grid.” That's an artist's conception of the Microsoft installation at left.


The grid connection is important. Some solar panels, for instance, sat useless through Hurricane Sandy because their inverters need grid power to operate. A battery backup is the solution there.


How far is Microsoft willing to go with this? Sean James, a research program manager at Microsoft’s Global Foundation Services at Microsoft, tells me the company is closely studying biogas. “Our Wyoming R&D Pilot project is designed to study methods for providing a stable, clean, scalable, and economically efficient power source for data centers,” he said. “Our hope is that this could become a best practice for use by our own facilities and other industries in the future as well.”


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MNN tease photo of data center: Shutterstock


Jim Motavalli ( @jmotavalli ) writes about cars, technology and the environmental world to anyone curious enough to ask.

Running big-draw server farms on fuel cells, solar and wind
The Internet uses more power than the auto industry. Microsoft and Google are trying to cut the carbon output of their server farms by investing in alternative