Data CenterPower and Cooling

Assessing Fuel Cells and Micro-turbines for Backup Data Center Power

Data center operators are always looking for ways to improve reliability and one of the main challenges in that effort is making sure the data center has a reliable source of electrical power.

To maintain 99.999% availability, or five 9s, a data center can’t be down for more than 5 minutes per year. As we all know, you can’t count on power companies to deliver that kind of reliability so it’s up to data center operators to determine the best backup plan in the case of an outage.

Backup generators and uninterruptible power supplies (UPS) are the traditional means of providing backup power for data centers. But of late there’s been talk about a couple of alternatives, namely fuel cells and micro-turbine generators.

A fuel cell is an electrochemical cell that involves a reaction between a fuel, such as liquid hydrogen, and an oxidant, such as liquid oxygen. The fuel cell converts the energy from the chemical reaction into electrical energy, heat, and water. Think of it as a battery that doesn’t require recharging.

Micro-turbine generators are small, self-contained high-speed power plants that usually include a turbine, compressor, generator, and power electronics to deliver the power. A high-speed gas turbine engine drives an electrical generator that can produce 20-100 kW of power when operating at a high speed.

The question is, do either of these technologies represent a viable, cost-effective alternative to traditional generators and UPSs for backup data center power?  Answering that question is the focus of an informative course, titled Alternative Power Generation Technologies, offered by Schneider Electric’s free online education program Energy University.

The online course walks you through a detailed analysis that looks at the question from multiple angles. It first runs through the modes of backup operation, including:

  • Standby mode, where a generator provides backup power in the event of a utility power failure, with a UPS used to keep equipment operating until the generator kicks in.
  • Continuous mode, which relies primarily on local power generator, with utility power used as a backup, again with a UPS to bridge between the two.
  • Utility interactive mode, in which a local power generator supplies the main data center power but operates in parallel with utility power, with any excess local power feeding the utility. Once again, a UPS is typically required to buffer the critical load from the raw utility power.

The course examines how cost-effective each of those modes is and the possibility of using fuel cells and/or micro-turbine generators in each scenario, and whether they can replace any of the traditional components. The short answer: in some cases, yes, but the TCO picture is typically not attractive – at least not yet.

Of course the issue is far more complex than that and, even if you are not considering fuel cells or micro-turbine generators, you’ll likely find it worthwhile to learn about the various technologies in question and architectures for providing fault tolerance. Like all Energy University courses, it doesn’t cost anything other than about an hour of your time. The Energy University site and its courses are easy to navigate and use, as you work at your own pace. And you can can earn education credits from more than 17 endorsing organizations. The Alternative Power Generation Technologies course, for example, is recognized for education credits by the IFMA, BICSI, the Building Performance Institute, Inc. (BPI) and others. You’ll find it under the Data Center category on the Energy University site. It’s quick and easy to register – you’ll be learning in no time.


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